About C-MOLD Releases

About C-MOLD Releases
The C-MOLD 98.7 general release, first shipped to customers in May 1998.

C-MOLD Incremental Release Notes:
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C-MOLD 98.12 C-MOLD 98.11 C-MOLD 98.10 C-MOLD 98.9 C-MOLD 98.6 C-MOLD 98.5 C-MOLD 98.4 C-MOLD 98.3 C-MOLD 98.2

The C-MOLD 98.1 general release, first shipped to customers in November 1997.

The previous general release, C-MOLD 97.7, shipped to customers in May 1997.

C-MOLD 98.7 Release Notes
The 98.7 release of C-MOLD is a general release to all customers with current Support & Update agreements. These notes describe what is new since the 98.1 general release in November 1997.

Contents
  Introduction Running C-MOLD  Keyfiles  Supported platforms  Installation procedure  For UNIX machine  For Windows NT 4.0 and 95 machines  Enhancements  Support for Exceed 6 added  X11 R6 run-time environment software required  Problems fixed  C-MOLD License Manager can be installed as a service C-MOLD Filling & Post-Filling  Enhancements  Negative coefficient of thermal expansion for fiber-filled materials allowed  Clamp-force calculation modified in cases where incompressible material model is specified  Problems fixed  Improved handling of cases where the input melt temperature is less than the transition temperature C-MOLD Filling/EZ  Enhancements  11 recommended ram-speed profile settings output C-MOLD Gas-Assisted Injection Molding  Enhancements  Improved handling of cases when the pre-set post-filling time is exceeded C-MOLD Cooling  Enhancements  No more overlapping cooling-channel elements  Reduced CPU time required C-MOLD Coolant Flow  Enhancements  Improved output format of the pressure drop in a cooling manifold  Problems fixed  Incorrect display of coolant flow rate when a pressure drop is specified for a cooling manifold C-MOLD Integrated Shrinkage & Warpage  Enhancements  Layer-based Residual Stress coupled with Fiber Orientation calculation

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 Fiber-orientation effect display available Material database changes  Resin database  Mold material database Known problems in this release  Windows stacking out of order

Introduction
In addition to twice-yearly general releases, our monthly incremental releases provide for timely problem corrections and the implementation of new features. When applicable, the incremental release version of a fix or enhancement is noted in the monthly summaries. For information on obtaining the latest monthly incremental release, contact your local CMOLD office. The C-MOLD Web site is also a good place to look for the latest information about our products. Most of the improvements in C-MOLD 98.7 relate to Shrinkage & Warpage simulation. The incremental enhancements introduced over the past two years are part of a long-term vision that is now coming to fruition with the release of C-MOLD 98.7. Major developments in C-MOLD 98.7 include the ability to incorporate "fast-cooling" pvT properties for semi-crystalline materials and the ability to couple layer-based residual stress with orientation-induced thermo-mechanical properties for fiber-filled materials. Table 1 lists the enhancements to and problems fixed in this latest general release of CMOLD, and gives the incremental version of the software in which the change was introduced. TABLE 1. Summary of changes to C-MOLD products in release 98.7. C-MOLD product C-MOLD on Windows NT and Windows 95 computers C-MOLD interactive modules on HP computers C-MOLD License Manager on Windows NT computers C-MOLD Filling & PostFilling Enhancement/problem fixed Support for Exceed 6 added X11 R6 run-time environment software required C-MOLD License Manager can be installed as a service Negative coefficient of thermal expansion for fiber-filled materials allowed Clamp-force calculation modified in cases where incompressible material model is specified Improved handling of cases where the input Introduced in release 98.2 98.5 98.7 98.3 98.4

98.4

C-MOLD Filling/EZ C-MOLD Gas-Assisted Injection Molding C-MOLD Cooling

C-MOLD Coolant Flow

C-MOLD Integrated Shrinkage & Warpage

melt temperature is less than the transition temperature 11 recommended ram-speed profile settings output Improved handling of cases when the preset post-filling time is exceeded No more overlapping cooling-channel elements Reduced CPU time required Improved output format of the pressure drop in a cooling manifold Incorrect display of coolant flow rate when a pressure drop is specified for a cooling manifold is fixed Layer-based Residual Stress coupled with Fiber Orientation calculation Fiber orientation effect display available

98.3 98.4 98.5 98.5 98.5 98.7

98.6 98.7

Running C-MOLD
Keyfiles
As long as your Support & Update agreement is current and you are updating from a 96.7 or higher version, your existing keyfile will enable this release. If you are updating directly to the 98.7 release from a version of C-MOLD earlier than 96.7, you will need a new keyfile. If using your existing keyfile with the 98.7 release results in an Inconsistent encryption code error, contact your local C-MOLD office to obtain your new keyfile. You can check your C-MOLD license key for the recorded Support & Update expiration date. Find the line with the key for C-MOLD that looks like this:
2eac 4f4a 8ah6 8d74 23d6 28gf d373 6k93 cmold NO EXPIRY 12/01/96 15users

The date in mm/dd/yy format is your Support & Update expiration date. To run version 98.7, this date must be after 03/31/98. If you have a question about your Support & Update agreement, please call your local C-MOLD office.

Supported platforms
The current release supports the hardware platform and operating system configurations given in Table 2, below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. TABLE 2. Hardware platform and operating system configurations supported by CMOLD 98.7. Hardware Platform DEC Alpha AXP DEC Alpha AXP NT HP 9000 IBM Intel-based PC 486, Pentium or Pentium Pro Intel-based PC Pentium or Pentium Pro SGI (MIPS I) SGI (MIPS IV) Sun SPARC Minimum C-MOLD OS Level Digital UNIX 4.0 Windows NT 4.0 HP-UX 10.20 AIX 4.2 Windows 95 Windows NT 4.0 IRIX 5.3 IRIX 6.2 Solaris 2.5 (SunOS 5.5)

Installation procedure
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or install CMOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator. Refer to the C-MOLD System Administrator Guide for setting up special configurations and/or troubleshooting system problems. It is distributed in hard copy form with this CMOLD 98.7 general release and is available on-line in HTML format from the documentation screens. Type cmdoc once C-MOLD is installed to access the on-line documentation set.

For UNIX machines
Follow these instructions to install C-MOLD on the following hardware platforms:
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DEC Alpha AXP, Digital UNIX v4.0

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HP 9000, HP-UX 10.20 IBM, AIX 4.2 SGI (MIPS I), IRIX 5.3 SGI (MIPS IV), IRIX 6.2 Sun SPARC, Solaris 2.5 (SunOS 5.5)

SGI users should install the MIPS IV version only on a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir 4 Type cd cdrom_dir 5 For all but HP computers, type ./install, and follow the on-screen instructions. HP: type ./INSTALL.\;1

For Windows NT 4.0 and 95 machines
Follow these instructions to install C-MOLD on the following hardware platforms:
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PC 486, Pentium, or Pentium Pro, Windows 95 PC Pentium or Pentium Pro, Windows NT 4.0 DEC Alpha AXP NT, Windows NT 4.0

1 Intel CPU: locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. DEC Alpha AXP CPU: locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. (where xxx corresponds to the particular release you are installing)

2 Run setup.exe.

Enhancements

Support for Exceed 6 added
On Windows NT and Windows 95 computers, C-MOLD supports Exceed 6. Changes in the location of locale information between Exceed 5 and 6 require a patch for versions of C-MOLD earlier than 98.2. Contact your local C-MOLD office for information about obtaining the patch if you are running an earlier version of C-MOLD and Exceed 6.

X11 R6 run-time environment software required
On HP computers, C-MOLD interactive modules now require X11 R6 run-time environment software. Versions earlier than C-MOLD 98.5 required R4 or R5.

Problems fixed

C-MOLD License Manager can be installed as a service
On Windows NT computers, the C-MOLD License Manager can now be installed as a service, allowing it to run in the background.

Installing the C-MOLD License Manager as a Windows NT service
Summary: 1. 2. 3. 4. Install the keyfile Make sure cmoldlmd works in a DOS window Install the service Start the service

The C-MOLD License Manager service consists of two parts. The first, cmoldlmd.exe, is the actual license manager. The second, cmlmdsrv.exe, interacts with Windows NT to run cmoldlmd in the background. You can also run cmoldlmd in the foreground, in a DOS window. It is much easier to resolve any key or license manager problems this way. 5. Before you can install the C-MOLD License Manager as a service, you must obtain and install your keyfile. (Refer to the C-MOLD System Administrator Guide for details about how to do this.)

6. Once you have installed your keyfile, start cmoldlmd in a DOS window to make sure that it can run correctly and there are no problems with the keyfile: a. Open a DOS window b. Change (cd) to the directory where C-MOLD is installed c. Run bin\cmoldlmd -cmold If the license manager starts correctly, proceed to the next step. If not, refer to the PC troubleshooting guide in Appendix C of the System Administrator Guide. 7. Once cmoldlmd runs successfully in a DOS window, you are ready to install it as a service: a. Open a DOS window b. Change (cd) to the directory where C-MOLD is installed c. Run cmlmdsrv -install 8. The C-MOLD License Manager is now installed as a service. It will start automaticaly the next time the the system is rebooted, or you can start it manually now: a. Open the Windows Control Panel b. Open the Services icon c. Select the C-MOLD License Manager from the list of services d. Click the START button.

Removing the service
You must remove the service before you can successfully uninstall C-MOLD: 9. Open a DOS window 10. Change (cd) to the directory where C-MOLD is installed 11. Run bin\cmlmdsrv -remove

Troubleshooting
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Service Specific Error 0

IfService Specific Error 0 occurs while starting the service, it means that cmoldlmd did not start correctly. When cmoldlmd runs as a service, all output is directed to a log file, cmlmdsrv.log, located in the C-MOLD\bin directory. This file can be checked for an indication of what the problem is. Remember that it is much easier to troubleshoot in a DOS window. If cmoldlmd does not start, refer to the PC troubleshooting guide in Appendix C of the System Administrator Guide.

C-MOLD Filling & Post-Filling

Enhancements

Negative coefficient of thermal expansion for fiber-filled materials allowed
In response to a user request, allowance for negative values of coefficient of thermal expansion for fiber-filled materials has been added.

Clamp-force calculation modified in cases where incompressible material model is specified
If an incompressible material model is specified, the clamp-force prediction at the end of filling has been modified to calculate using the final pressure distribution at the instant before complete fill. This reduces the predicted clamp force to a reasonable value; otherwise, the incompressible material assumption would cause the entrance pressure to be propagated throughout the cavity. Note that normally, pvT data is used, and polymer compressibility is accounted for in the material model. You can force the program to use an incompressible material model by manually adjusting the material input file.

Problems fixed

Improved handling of cases where the input melt temperature is less than the transition temperature
If the input melt temperature is less than the material's transition temperature, error message 99621 is displayed, and execution stops. If the input melt temperature is less than b5 of the pvT model, a warning message is issued, and the program continues to calculate. Note that normally, using a melt temperature near the transition temperature or b5 does not match the physical processing conditions and indicates either a problem in the material selection or data, or the processing conditions.

C-MOLD Filling/EZ
Enhancements

11 recommended ram-speed profile settings output
A recommended ram-speed profile is one of the outputs from C-MOLD Filling/EZ. Using the recommended ram-speed profile will keep melt-front speeds more uniform, resulting in a molded part with fewer molded-in stresses. Ram-speed profile settings are output for the number of settings specified in the process conditions file. Previously, if you had specified two settings in the process

conditions file, for example at 0% of stroke and 100% of stroke, only two suggested settings would be output. In response to a user request, the program has been changed to output 11 settings, even if only two settings are specified in the process conditions file.

C-MOLD Gas Assisted Injection Molding
Enhancements

Improved handling of cases when the pre-set post-filling time is exceeded
When the pre-set post-filling time is exceeded, output follows the normal short-shot procedure instead of stopping immediately. This provides melt-front advancement information for review up to the time the short shot occurs.

C-MOLD Cooling
Enhancements

No more overlapping cooling channel elements.
When a bend occurs in a cooling channel, it is possible for the channel elements to overlap in the model of the cooling system. This overlap may cause problems in the numerical simulation. To overcome such problems, in previous versions of CMOLD Cooling, the channel elements were treated as disconnected, and related elements were shortened or ignored to minimize the effect of the overlap. This treatment, however, also introduced some error in the solution, because the temperature and heat flux calculations could not vary continuously along the disconnected channel elements, as shown in Figure 1. In the enhanced C-MOLD Cooling (98.5 and later releases), a new model is used to deal with cooling channel elements, and it is no longer necessary to disconnect the channel elements to avoid overlap. Thus all physical parameters can vary continuously along the cooling channels (see Figure 2), and the accuracy of simulation is improved.

Figure 1. Cooling channel efficiency results from the old C-MOLD Cooling. The disconnected elements and the discontinuous results at the bends in the channel are easily seen.
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Figure 2. Improved cooling channel efficiency results from the enhanced CMOLD Cooling (version 98.5 and later). The results are continuous along the entire length of the channel.

Reduced CPU time required.
The boundary element method (BEM) is used in mold-cooling simulation, which relies on a system of equations. Since the related matrix is full and very large, it is very time-consuming to solve this system of equations directly; instead, an iterative solution method is used. In an iterative method, there are three key factors:
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Initial solution: this is an assumption of the value of the real solution, which is used as the starting point for the iterations. How good the assumption is (how close the assumed value is to the real value) directly affects the running time required to complete the simulation. Solver: this refers to the specific iterative technique that is used, for example, the Gauss-Seidel solver, CG solver, and so on. The solver determines the convergence rate of the solution. Convergence criterion: this specifies the acceptable level of approximation allowed between iterations in solving the system of equations.

In the enhanced C-MOLD Cooling, all of these key factors have been changed. A new initial solution and a new solver are employed, which make the enhanced CMOLD Cooling run much faster than older versions. In addition, a new convergence criterion is used. A solution is considered to be converged when the residual is small enough. In a matrix equation [A][x]=[b], the residual is defined as [R]=[A][x]-[b], which is the accuracy of the solution. In older versions of C-MOLD Cooling, an indirect method, other than the residual, was used as the convergence parameter. This indirect method checked the change in the solution value from one iteration to the next, and if the change was less than the convergence criterion, the solution was assumed to be converged. Sometimes this indirect method failed to reflect the real convergence approximation. In the

enhanced C-MOLD Cooling, since the storage of BEM elements has been improved, it has become possible to use the residual directly as the convergence parameter, which eliminates a source of error that occurred in the older version.

Impact on solution accuracy
In some cases, it is possible that the enhanced C-MOLD Cooling (version 98.5 and later) and older versions would result in different solutions. To determine which is the more accurate solution, compare the residuals. The enhanced C-MOLD Cooling uses the residual as the convergence parameter. While the old C-MOLD Cooling also gives the residual, it is not used as the convergence parameter. The result with the smallest residual value is the more accurate solution. Using the enhanced CMOLD Cooling will always require fewer iterations to reach the solution than were required with the old version, and in addition, the results of the enhanced C-MOLD Cooling are often more accurate as well. For example, compare these results of the enhanced C-MOLD Cooling and the older version when the simulation is run on a simple rectangular plate with the convergence criterion specified as 0.001: Enhanced C-MOLD Cooling (98.5 and later) first iteration convergence parameter last iteration convergence parameter number of iterations residual after last iteration mold wall temperature range temperature difference range 1.1618E-01 % 7.0136E-04 % 6 7.0136E-06
(same as last iteration convergence parameter, above)

Old C-MOLD Cooling (98.4 and earlier) 3.4129E+00 % 9.9572E-04 % 35 2.8376E-05 27.25 - 49.75 8.14 - 22.49

29.05 - 51.35 8.04 - 21.93

This example clearly shows us why the enhanced C-MOLD Cooling runs faster. It can also be seen that in the old C-MOLD Cooling, the residual after the last iteration is much larger than the convergence parameter in the last iteration. However, in the enhanced C-MOLD Cooling, these values are the same, so the convergence parameter becomes a true measure of the solution accuracy.

C-MOLD Coolant Flow

Enhancements

Improved output format of the pressure drop in a cooling manifold
The output format of pressure drop in cooling manifold has been changed. The change will affect the display of coolant pressure drop only at junctions of regular cooling channels with baffles or bubblers. In modeling, a baffle or bubbler is defined by at least two nodes: one for the coolant entrance, and the other for the free end where the coolant changes direction (see Figure 3-29 and Figure 3-30 in the C-MOLD Modeler & Visualizer User's Guide for additional details).

Figure 3. Model representation of baffle or bubbler. It is obvious that at the entrance node, the pressure is discontinuous at the two sides of the baffle plate or bubbler plate. Therefore, an abrupt change of pressure at the entrance node should be seen in the graphical display. In the baffle or bubbler, however, the pressure drop of entering flow and returning flow is still displayed on the element(s) from the entrance node to the free-end node. In other words, after the code change, the coolant pressure at the free-end node should be the same as the coolant pressure at the entrance node from the exit side of the baffle or bubbler. This change has no effects on results of C-MOLD Cooling simulation. Figure 4 and Figure 5 show the displays of coolant pressure before and after the code change, respectively.

Figure 4. (Click to zoom in.) Coolant Figure 5. (Click to zoom in.) Improved pressure display before the code change. coolant pressure display after the code change.

Problems fixed

Incorrect display of coolant flow rate when a pressure drop is specified for a cooling manifold
If a pressure drop was specified for a cooling manifold, the coolant flow rate given in the text report would be zero. The calculations in the Coolant Flow and subsequent Cooling simulations were still correct, except the values were incorrectly reported. This problem has been fixed.

C-MOLD Integrated Shrinkage & Warpage
Enhancements

Layer-based Residual Stress coupled with Fiber Orientation calculation What is new
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The Fiber Orientation option for Integrated Shrinkage & Warpage simulation gives improved deformation results compared to previous versions, because the residual-stress and thermo-mechanical properties calculations have been coupled with the fiber-orientation calculation. The interface between C-MOLD Residual Stress and C-MOLD Shrinkage & Warpage is now layer-based, which is different from the equivalent loadings used by previous versions. The number of layers used for the Residual Stress calculation is the same as the number of layers specified for Filling & Post-Filling simulation. The molded-in residual stress after part ejection is now an optional output as requested by users, instead of in-cavity residual stress. C-MOLD Polymer Laboratory now provides fast-cooling pvT testing for semi-crystalline materials. Shrinkage & Warpage predictions can be improved to within 10% accuracy by using the fast-cooling pvT data.

Terminology
What is in-cavity residual stress? The in-cavity residual stress refers to the internal stress accumulated during the solidification of the part inside the cavity until the temperature and pressure within the cavity drop to ambient conditions. This in-cavity residual stress is the driving force of part shrinkage and warpage after ejection. It is calculated by C-MOLD Residual Stress and stored in the interface file to C-MOLD Shrinkage & Warpage (filename.ppt). In-cavity residual stress cannot be measured on a molded part because of the stress relaxation that occurs after ejection. What is molded-in residual stress? After part ejection, the constraints from the mold cavity are released, and the part is free to shrink and deform. After it settles to an equilibrium shape, the remaining stress inside the part is called molded-in residual stress, or simply, residual stress. The difference between in-cavity residual stress and molded-in residual stress is whether or not the constraints imposed by the cavity on the part have been released. Molded-in residual stress can be measured on a molded part. This release of CMOLD includes the option to output the molded-in residual stress. Why Integrated Shrinkage & Warpage? The predicted final deformation of a part after ejection is what a user expects a simulation to produce. The intermediate, in-cavity residual stress has no practical application for users, and therefore, it is no longer included in the C-MOLD output file. C-MOLD Residual Stress and C-MOLD Shrinkage & Warpage are now tightly integrated with layer-based residual stress and mechanical properties calculations; this feature is not provided with interfaces to other, general-purpose structural analysis programs. Why fast-cooling pvT data? The physical properties of semi-crystalline materials (such as PET, PBT, Nylon, etc.) depend on the degree of crystallinity. During the injection molding process, the material's crystallinity depends on several processing parameters, especially on the cooling rate. Conventional pvT testing is based on measurements at equilibrium or at a very slow cooling rate. The pvT behavior of semi-crystalline materials can be quite different under a fast cooling rate, therefore resulting in different amounts of shrinkage. C-MOLD recently developed a technique to measure and predict pvT under the fast-cooling conditions similar to an injection molding process. It has been verified by the Polymers Department of the GM Research and Development Center (under the NIST-sponsored TED venture) that using fast-cooling pvT data in the simulation can improve the shrinkage prediction to within 10% of measured values for semi-crystalline materials. C-MOLD Polymer Laboratory offers the fast-

cooling pvT material testing service. Check with your resin suppliers or C-MOLD Polymer Laboratory for details.

Residual Stress and thermo-mechanical properties calculations coupled with Fiber Orientation calculation
Previous versions of C-MOLD used the thermo-mechanical properties in the flow and transverse directions for the Shrinkage & Warpage calculations. In cases where the material is fiber-reinforced, the local thermo-mechanical properties would depend on the fiber orientation. This new version of C-MOLD calculates the local thermo-mechanical properties based on predicted fiber orientation, and the local residual stress corresponds to the local thermo-mechanical properties. For fiber-reinforced materials, the Shrinkage & Warpage predictions are now based on the residual stress and thermo-mechanical properties coupled with the predicted fiber orientation. Users can add a service-loading simulation after the residual-stress calculation in order to predict part performance under service. The influence of fiber orientation and molded-in residual stress can be considered in the structural design of plastic parts.

Layer-Based Information vs. Equivalent Loadings
In previous versions of C-MOLD Residual Stress, equivalent loadings were output to the interface file and used for Shrinkage & Warpage calculation. Equivalent loadings were calculated for each node and element based on the in-cavity residual stress that was distributed through the thickness. Such equivalent loadings are self-balanced before part deformation, but can become unbalanced after large deformation, resulting in a rigid-body motion to the Shrinkage & Warpage prediction. After introducing the geometric non-linear analysis in C-MOLD Shrinkage & Warpage, it became possible to calculate large deformations. When this happens, the originally balanced equivalent loadings may become unbalanced. It is not possible to perform a geometric non-linear Shrinkage & Warpage simulation with equivalent loadings based on in-cavity residual stress. The in-cavity residual stress should be used directly, because it is always self-balanced, no matter how the part is deformed. In-cavity residual stress now is used directly for Shrinkage & Warpage prediction. In-cavity residual stress is predicted for each layer of each element.

In previous versions of C-MOLD Residual Stress, a part was assumed homogeneous, which means that thermo-mechanical properties (isotropic or transversely isotropic) were assumed to be uniformly distributed. This assumption is no longer valid for fiber-filled composites; now, layer-based thermo-mechanical properties are calculated for each layer of each element and used for Shrinkage & Warpage calculation. The layer-based information is stored in filename.ppt and used as input to the final Shrinkage & Warpage simulation.

How to Use the New Features
All of these improvements were internal to the C-MOLD modules. From the user's point of view, there is almost no change in how to prepare for and launch the Integrated Shrinkage & Warpage simulation.
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T-CODE 00614 and T-CODE 00615 have been added to the parameter file (filename.par) to control the various layer-based stress outputs. Most of these stresses are useful only to analysts. The amount of data can be large because stress data is stored for each layer of each element. These TCODEs are used by C-MOLD Shrinkage & Warpage module only. TCODE 00615 is used only when service loadings are defined.
00614 NONE NONE 0-4 0 no molded-in stress output 1 for Principal Residual Stress (Molded-in) 2 3 4 for option 1 plus Max Shear Stress for option 1 plus Mises-Hencky Stress for all the stress outputs

T-CODE# Equation: Units: Range: Default Value: Option output Option Option Option T-CODE# Equation: Units:

00615 NONE NONE

Range: 0-4 Default Value: 0 no stress output for service loading and combined with service loading Option 1 for Principal Residual Stress (service) and (molded-in + service) output Option 2 for option 1 plus Max Shear Stress

Option Option

3 4

for option 1 plus Mises-Hencky Stress for all the stress outputs

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The layer-based, in-cavity residual stresses and/or thermo-mechanical properties are stored in an ASCII interface file, filename.ppt, which is in CMOLD output file format. Translation from this file to an equivalent input file to any other structural analysis package capable of doing layer-based shell analysis is possible by anyone who knows both file formats. All the T-CODE's used for geometric non-linear calculations in C-MOLD Shrinkage & Warpage are still effective. To get fast-cooling pvT data requires additional material testing and data reduction. Data has been generated for only a few resins so far. Due to the limited number of resins tested, at this time, the fast cooling pvT data is not included in the C-MOLD Resin Database. Contact your resin suppliers or C-MOLD Polymer Laboratory for information about acquiring this data and requesting testing services.

Fiber-orientation effect display available
Fiber-orientation effect now is produced as a reference to help users identify how much fiber orientation will influence the final part deformation. This functionality is available automatically when a fiber-filled composite material is chosen and CMOLD Fiber Orientation is run as part of the Integrated Shrinkage & Warpage simulation. The fiber-orientation effect is defined as the difference between the following two displacement solutions:
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Final displacement solution due to all causes, and Displacement solution due to assuming randomly distributed fibers in the planar directions and uniformly distributed fibers through the thickness

Unlike the previously available non-uniform shrinkage and unbalanced cooling causes of displacement, the displacement due to the fiber-orientation effect cannot be added into the total displacement with the other two, because they are mutually dependent. However, from the definition of the dataset, it can readily be seen that the sum of the displacement due to the fiber-orientation effect and the displacement due to assuming two-dimensional, randomly distributed fibers would be the total displacement. Users do not need to change any inputs to invoke the calculation of fiberorientation effect. When Fiber Orientation is chosen for the Integrated Shrinkage & Warpage simulation, the fiber-orientation effect is automatically calculated. In the output file, filename.ow3, one more set of displacement data is produced for visualization. In the interface file, filename.ppt, a scalar set of two-

dimensional, randomly distributed fiber-filled composite properties is produced in the beginning, and one more in-cavity residual stress value is produced for each layer of each element. The fiber-orientation effect can be viewed by using C-MOLD Visualizer after Shrinkage & Warpage results have been loaded selected. Users then can select Displacement (randomly oriented fibers) or X(Y, Z)-displacement (randomly oriented fibers) from the list of available datasets to display the result. Normally, the displacement due to the fiber-orientation effect is of the same order of magnitude as that of the displacement due to non-uniform shrinkage.

Material database changes
Resin database
The C-MOLD 98.7 Resin Database has grown to a total of 4,724 resins with viscosity data sufficient for C-MOLD Filling simulation. Of these 957 resins include pvT data, 371 include juncture-loss data, and 206 include mechanical properties data. Since the previous general release, 426 new resins have been added to the database. Changes to the C-MOLD Resin Database since the 98.1 general release are detailed in the appendix. Please refer to the Search the C-MOLD Resin Database page on C-MOLD's Web site to see what data is available.

Mold material database
The thermal conductivity value for Aluminum has been corrected. The new value given is 220 W/m°K.

Known problems in this release
Windows stacking out of order
On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the Save Design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection, either Run Now, Run as Batch, or Cancel will be processed. The workaround is to save your design before entering the Design Diagnostics dialog.

C-MOLD 98.12 Release Notes
The C-MOLD 98.12 incremental release.
The 98.12 release of C-MOLD is an incremental release. Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features for you. Our last general release to all customers with current Support & Update agreements was made in May 1998. These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office.

Supported platforms.
The current release supports the hardware platform and operating system configurations given in the table below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. Hardware Platform DEC Alpha AXP DEC Alpha AXP NT HP 9000 IBM Intel-based PC 486, Pentium or Pentium Pro Intel-based PC Pentium or Pentium Pro SGI (MIPS I) SGI (MIPS IV) Sun SPARC Minimum C-MOLD OS Level Digital UNIX 4.0 Windows NT 4.0 HP-UX 10.20 AIX 4.2 Windows 95 Windows NT 4.0 IRIX 5.3 IRIX 6.2 Solaris 2.5 (SunOS 5.5)

Installation procedure.
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or install CMOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator.

Refer to the C-MOLD System Administrator Guide for setting up special configurations and/or troubleshooting system problems. It was distributed in hard copy form with the CMOLD 98.1 general release and is available on-line in HTML format from the documentation screens. Type cmdoc once C-MOLD is installed to access the on-line documentation set.

For UNIX machines
Follow these instructions to install C-MOLD on the following hardware platforms:
• • • • • •

DEC Alpha AXP, Digital UNIX v4.0 HP 9000, HP-UX 10.20 IBM, AIX 4.2 SGI (MIPS I), IRIX 5.3 SGI (MIPS IV), IRIX 6.2 Sun SPARC, Solaris 2.5 (SunOS 5.5)

SGI users should install the MIPS IV version only on a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir 4 Type cd cdrom_dir 5 For all but HP computers, type ./install, and follow the on-screen instructions. HP: type ./INSTALL.\;1

For Windows NT 4.0 and 95 machines
Follow these instructions to install C-MOLD on the following hardware platforms:

• • •

PC 486, Pentium, or Pentium Pro, Windows 95 PC Pentium or Pentium Pro, Windows NT 4.0 DEC Alpha AXP NT, Windows NT 4.0

1 Intel CPU: locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. DEC Alpha AXP CPU: locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. (where xxx corresponds to the particular release you are installing) 2 Run setup.exe.

Enhancements introduced in this release.
C-MOLD Control Panel
For the regular thermoplastic injection molding and gas-assisted injection molding processes, the following obsolete TCODEs have been removed from the parameter file templates: TCODE # Description 300 Pressure convergence criterion 301 Flow-rate convergence criterion 400 Max # of pressure iterations 401 Max # of flow-rate iterations 522 Age of mold (COOL) For the gas-assisted injection molding process, TCODEs have been added to the material and process templates for specifying coolant, mold materials, and additional processing parameters associated with the capability to run Productivity and Performance Solution simulations. For the thermoplastic injection molding process, the Productivity Solution Integrated Filling and Cooling selection performs a Filling & Post-Filling simulation and then performs a Cooling simulation. The heat load from the Filling & Post-Filling simulation is used as a boundary condition for the Cooling simulation. Previously, only a Filling simulation was performed, and this output was interfaced to the Cooling simulation. Since the post-filling time is longer than the filling time, the effect of the heat load on the mold is greater under the new configuration, which improves the accuracy of the resulting integrated solution.

C-MOLD License Manager
C-MOLD License Manager now checks license dependencies when a C-MOLD module is launched. For example, the C-MOLD Gas-Assisted Injection Molding module requires CMOLD Filling & Post-Filling, and the C-MOLD Microchip Encapsulation module requires C-MOLD Reactive Molding and C-MOLD Shrinkage & Warpage. The License Manager now checks that each prerequisite license is available. Refer to the C-MOLD product descriptions on our Web site (http://www.cmold.com/cm_info/solutions.html) for information about product prerequisites.

ANSYS to C-MOLD mesh translator
The ANSYS to C-MOLD mesh translator executable image name changed from ansys to ans2cm. This removes a possible conflict that could arise from having the same executable name used by both ANSYS and C-MOLD. If you access the mesh translator from the graphical user interface in C-MOLD Control Panel or C-MOLD Modeler, you will see no difference. Only if you run the translator from the command line or from some custombuilt scripts will you need to take into account the new name.

Problems fixed in this release.
C-MOLD Cooling
Premature exit and non-converged solutions Significant changes to C-MOLD Cooling simulation were introduced in the CMOLD 98.7 general release (refer to the C-MOLD 98.7 Release Notes for details). These changes were introduced to remove the limitation of cooling-channel overlap at bends and to reduce the computation time required. Although both objectives were achieved, a problem occurred that caused discrepancies in results for some cases, compared to results from previous versions of the software. The program could exit from the iterations prematurely, before the solution was converged. It was observed in some cases that the resulting mold-wall temperature was unreasonably uniform and the temperature difference was too small, both of which are due to insufficient iterations of the solution. A partial workaround exists for C-MOLD Cooling 98.7 users: simply set the Max # of iterations to a desired number and and reduce the Mold temp convergence criterion to a very small value. For example:
313 413 1 1 Mold temp convergence criterion 0.00001 Max # of cooling iterations 10

In most cases, using the workaround should cause the simulation to continue the iterations until the maximum number is reached.

This premature exit and some other minor problems have been identified and fixed in the C-MOLD 98.12 incremental release. We have tested C-MOLD Cooling 98.12 on all of the cases where problems with the 98.7 release were reported. The C-MOLD Cooling 98.12 results are comparable to results of C-MOLD Cooling 98.1 (before the changes introduced in the 98.7 general release). Users who experience problems with C-MOLD Cooling 98.7 simulation should upgrade to C-MOLD 98.12 (or later versions). Interface file changed The interface file from C-MOLD Filling & Post-Filling to C-MOLD Cooling, formerly filename.PFC, is replaced in C-MOLD 98.12 by filename.PPC. The new interface file enables C-MOLD Cooling to be integrated with C-MOLD GasAssisted Injection Molding to implement the new Productivity Solution and Performance Solution capabilities for the gas-assisted injection molding process.

Summary of benefits of C-MOLD Cooling 98.12:
1. Cooling-channel element size is no longer limited. Users now should set the mesh size of regular channels, baffles and bubblers to the same global mesh size used by runners and triangular elements. In contrast, in C-MOLD Cooling 98.1, the channel element length had to be approximately 3 to 5 times the diameter to avoid overlap problems at bends. The smaller channel element size possible in C-MOLD Cooling 98.12 results in a more accurate cooling solution, especially when the cooling channel is very close to the mold wall. 2. The C-MOLD Cooling 98.12 Cooling simulation is considerably faster than the 98.1 simulation for the same converged solution. 3. C-MOLD Cooling 98.12 simulation now is integrated with C-MOLD Gas-Assisted Injection Molding to provide Productivity Solution and Performance Solution capabilities. For example, now it is possible to predict the warpage of gas-assist parts due to mold-wall temperature differences. Note that for a successful C-MOLD Cooling simulation of a gas-assist part, connectors cannot be used when modeling the gas channels. C-MOLD Cooling does not handle connector elements between 1D (part runner) elements and triangular elements in the part mesh.

Known problems in this release.
On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the Save Design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection, either Run

Now, Run as Batch, or Cancel will be processed. The workaround is to save your design before entering the Design Diagnostics dialog.

Resin database changes.
Changes to the C-MOLD Resin Database since the 98.11 incremental release are detailed in the appendix. Please refer to the Search the C-MOLD Resin Database page on C-MOLD's Web site to see what data is available.

Copyright 1998 Advanced CAE Technology, Inc. All Rights Reserved.

Web Path Name: /C-MOLD_develop/del/v9812.html Security Classification: proprietary

C-MOLD 98.11 Release Notes
The C-MOLD 98.11 incremental release.
The 98.11 release of C-MOLD is an incremental release. Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features for you. Our last general release to all customers with current Support & Update agreements was made in May 1998. These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office.

Supported platforms.
The current release supports the hardware platform and operating system configurations given in the table below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. Hardware Platform DEC Alpha AXP DEC Alpha AXP NT HP 9000 IBM Intel-based PC 486, Pentium or Pentium Pro Intel-based PC Pentium or Pentium Pro SGI (MIPS I) SGI (MIPS IV) Sun SPARC Minimum C-MOLD OS Level Digital UNIX 4.0 Windows NT 4.0 HP-UX 10.20 AIX 4.2 Windows 95 Windows NT 4.0 IRIX 5.3 IRIX 6.2 Solaris 2.5 (SunOS 5.5)

Installation procedure.
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or install CMOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator.

Refer to the C-MOLD System Administrator Guide for setting up special configurations and/or troubleshooting system problems. It was distributed in hard copy form with the CMOLD 98.1 general release and is available on-line in HTML format from the documentation screens. Type cmdoc once C-MOLD is installed to access the on-line documentation set.

For UNIX machines
Follow these instructions to install C-MOLD on the following hardware platforms:
• • • • • •

DEC Alpha AXP, Digital UNIX v4.0 HP 9000, HP-UX 10.20 IBM, AIX 4.2 SGI (MIPS I), IRIX 5.3 SGI (MIPS IV), IRIX 6.2 Sun SPARC, Solaris 2.5 (SunOS 5.5)

SGI users should install the MIPS IV version only on a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir 4 Type cd cdrom_dir 5 For all but HP computers, type ./install, and follow the on-screen instructions. HP: type ./INSTALL.\;1

For Windows NT 4.0 and 95 machines
Follow these instructions to install C-MOLD on the following hardware platforms:

• • •

PC 486, Pentium, or Pentium Pro, Windows 95 PC Pentium or Pentium Pro, Windows NT 4.0 DEC Alpha AXP NT, Windows NT 4.0

1 Intel CPU: locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. DEC Alpha AXP CPU: locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. (where xxx corresponds to the particular release you are installing) 2 Run setup.exe.

Enhancements introduced in this release.
Beta Test of Gas-Assisted Injection Molding Performance Solution
In this C-MOLD 98.11 incremental release, Performance Solution capability is extended to the gas-assisted injection molding process. This test version of the new functionality enables simulation of mold filling through shrinkage and warpage for gas-assist applications. (C-MOLD Performance Solution packages are available commercially for traditional injection molding and injection/compression molding.) Extending the Performance Solution capability to gas-assist applications is possible because of the layerbased residual stress calculation introduced in the 98.5 incremental release and distributed to all users with current Support & Update Service in the 98.7 general release (May 1998). Customers with current Support & Update Service who license a Performance Solution package for injection molding and C-MOLD Gas-Assisted Injection Molding can test the new capability included in this release. In this test version, users must access the new capability through the command line interface. Type cgas3w to run the enhanced GasAssisted Injection Molding simulation. After it finishes successfully, type cwarp98 to run C-MOLD Shrinkage & Warpage. Among other changes, users will notice two new data sets are available, which define the upper and lower resin-gas interface locations. C-MOLD plans to extend Performance Solution capability to other molding processes in future releases.

Problems fixed in this release.
C-MOLD Shrinkage & Warpage A problem in C-MOLD Shrinkage & Warpage 98.7 that could produce inconsistent results when the temperature difference between consecutive time steps is very small has been corrected in the C-MOLD 98.10 and later incremental releases. C-MOLD Fiber Orientation

Previously, C-MOLD Fiber Orientation generated many non-convergence warning messages. These have been consolidated to a single warning message which indicates the labels of the non-converged elements. Process Estimator on Windows 95/NT computers: A problem that occurred when adding multiple materials to the thermoplastic resin data via .fit files has been corrected. Previously, only the most recently customerentered flow data would be accessible. All data provided in the standard C-MOLD Database was unaffected. C-MOLD License Manager on SGI MIPS IV computers: A problem that prevented C-MOLD applications from connecting to the License Manager has been corrected. Previously, the workaround was to run the IRIX 5.2 version of C-MOLD. Note that with this problem correction, 64-bit IRIX 6.2 or higher is required to run C-MOLD on SGI MIPS IV computers. C-MOLD on IBM computers: C-MOLD for IBM computers now is built with compilers and libraries included with the AIX 4.1.5 release. Previously, C-MOLD was built with AIX 3.2.5 compilers and libraries. Customers running earlier versions of AIX will need to upgrade their operating system level. Our stated operating system requirement for C-MOLD remains at AIX 4.2.

Known problems in this release.
On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the Save Design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection, either Run Now, Run as Batch, or Cancel will be processed. The workaround is to save your design before entering the Design Diagnostics dialog.

Resin database changes.
Please refer to the Search the C-MOLD Resin Database page on C-MOLD's Web site to see what data is available. Changes to the C-MOLD Resin Database since the C-MOLD 98.9 incremental release are detailed in the appendix.

Copyright 1998 Advanced CAE Technology, Inc. All Rights Reserved.

Web Path Name: /C-MOLD_develop/del/v9811.html Security Classification: proprietary

C-MOLD 98.10 Release Notes
The C-MOLD 98.10 incremental release.
The 98.10 release of C-MOLD is an incremental release. Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features for you. Our last general release to all customers with current Support & Update agreements was made in May 1998. These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office.

Supported platforms.
The current release supports the hardware platform and operating system configurations given in the table below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. Hardware Platform DEC Alpha AXP DEC Alpha AXP NT HP 9000 IBM Intel-based PC 486, Pentium or Pentium Pro Intel-based PC Pentium or Pentium Pro SGI (MIPS I) SGI (MIPS IV) Sun SPARC Minimum C-MOLD OS Level Digital UNIX 4.0 Windows NT 4.0 HP-UX 10.20 AIX 4.2 Windows 95 Windows NT 4.0 IRIX 5.3 IRIX 6.2 Solaris 2.5 (SunOS 5.5)

Installation procedure.
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or install CMOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator.

Refer to the C-MOLD System Administrator Guide for setting up special configurations and/or troubleshooting system problems. It was distributed in hard copy form with the CMOLD 98.1 general release and is available on-line in HTML format from the documentation screens. Type cmdoc once C-MOLD is installed to access the on-line documentation set.

For UNIX machines
Follow these instructions to install C-MOLD on the following hardware platforms:
• • • • • •

DEC Alpha AXP, Digital UNIX v4.0 HP 9000, HP-UX 10.20 IBM, AIX 4.2 SGI (MIPS I), IRIX 5.3 SGI (MIPS IV), IRIX 6.2 Sun SPARC, Solaris 2.5 (SunOS 5.5)

SGI users should install the MIPS IV version only on a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir 4 Type cd cdrom_dir 5 For all but HP computers, type ./install, and follow the on-screen instructions. HP: type ./INSTALL.\;1

For Windows NT 4.0 and 95 machines
Follow these instructions to install C-MOLD on the following hardware platforms:

• • •

PC 486, Pentium, or Pentium Pro, Windows 95 PC Pentium or Pentium Pro, Windows NT 4.0 DEC Alpha AXP NT, Windows NT 4.0

1 Intel CPU: locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. DEC Alpha AXP CPU: locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. (where xxx corresponds to the particular release you are installing) 2 Run setup.exe.

Problems fixed in this release.
In C-MOLD Modeler on DEC Alpha NT computers: Protection for a situation involved with creating tangent lines that resulted in a divide-by-zero error has been added. In C-MOLD Cooling on HP computers: A problem that caused a core dump when running the simulation with a very large model has been fixed. In C-MOLD Fiber Orientation on HP computers: A problem that caused non-convergence of the fiber-orientation calculation has been fixed. In C-MOLD Residual Stress: A problem that resulted in unreasonably large residual stress values when the temperature difference between consecutive time steps was very small has been fixed.

Known problems in this release.
On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the Save Design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection, either Run Now, Run as Batch, or Cancel will be processed. The workaround is to save your design before entering the Design Diagnostics dialog.

Resin database changes.

Please refer to the Search the C-MOLD Resin Database page on C-MOLD's Web site to see what data is available.

C-MOLD 98.9 Release Notes
The C-MOLD 98.9 incremental release.
The 98.9 release of C-MOLD is an incremental release. Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features for you. Our last general release to all customers with current Support & Update agreements was made in May 1998. These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office.

Supported platforms.
The current release supports the hardware platform and operating system configurations given in the table below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. Hardware Platform DEC Alpha AXP DEC Alpha AXP NT HP 9000 IBM Intel-based PC 486, Pentium or Pentium Pro Intel-based PC Pentium or Pentium Pro SGI (MIPS I) SGI (MIPS IV) Sun SPARC Minimum C-MOLD OS Level Digital UNIX 4.0 Windows NT 4.0 HP-UX 10.20 AIX 4.2 Windows 95 Windows NT 4.0 IRIX 5.3 IRIX 6.2 Solaris 2.5 (SunOS 5.5)

Installation procedure.
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or install CMOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator.

Refer to the C-MOLD System Administrator Guide for setting up special configurations and/or troubleshooting system problems. It was distributed in hard copy form with the CMOLD 98.1 general release and is available on-line in HTML format from the documentation screens. Type cmdoc once C-MOLD is installed to access the on-line documentation set.

For UNIX machines
Follow these instructions to install C-MOLD on the following hardware platforms:
• • • • • •

DEC Alpha AXP, Digital UNIX v4.0 HP 9000, HP-UX 10.20 IBM, AIX 4.2 SGI (MIPS I), IRIX 5.3 SGI (MIPS IV), IRIX 6.2 Sun SPARC, Solaris 2.5 (SunOS 5.5)

SGI users should install the MIPS IV version only on a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir 4 Type cd cdrom_dir 5 For all but HP computers, type ./install, and follow the on-screen instructions. HP: type ./INSTALL.\;1

For Windows NT 4.0 and 95 machines
Follow these instructions to install C-MOLD on the following hardware platforms:

• • •

PC 486, Pentium, or Pentium Pro, Windows 95 PC Pentium or Pentium Pro, Windows NT 4.0 DEC Alpha AXP NT, Windows NT 4.0

1 Intel CPU: locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. DEC Alpha AXP CPU: locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. (where xxx corresponds to the particular release you are installing) 2 Run setup.exe.

Enhancements introduced in this release.
Improved weld-line prediction.
C-MOLD's weld-line prediction has been improved to better capture weld (meld, knit) lines that occur due to melt-front hesitation during filling.

Known problems in this release.
On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the Save Design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection, either Run Now, Run as Batch, or Cancel will be processed. The workaround is to save your design before entering the Design Diagnostics dialog.

Resin database changes.
Please refer to the Search the C-MOLD Resin Database page on C-MOLD's Web site to see what data is available.

C-MOLD 98.6 Release Notes
The C-MOLD 98.6 incremental release.
The 98.6 release of C-MOLD is an incremental release. Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features for you. Our last general release to all customers with current Support & Update agreements was made in November 1997. These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office.

Supported platforms.
The current release supports the hardware platform and operating system configurations given in the table below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. Hardware Platform DEC Alpha AXP DEC Alpha AXP NT HP 9000 IBM Intel-based PC 486, Pentium or Pentium Pro Intel-based PC Pentium or Pentium Pro SGI (MIPS I) SGI (MIPS IV) Sun SPARC Minimum C-MOLD OS Level Digital UNIX 4.0 Windows NT 4.0 HP-UX 10.20 AIX 4.2 Windows 95 Windows NT 4.0 IRIX 5.3 IRIX 6.2 Solaris 2.5 (SunOS 5.5)

Installation procedure.
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or install CMOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator.

Refer to the C-MOLD System Administrator Guide for setting up special configurations and/or troubleshooting system problems. It was distributed in hard copy form with the CMOLD 98.1 general release and is available on-line in HTML format from the documentation screens. Type cmdoc once C-MOLD is installed to access the on-line documentation set.

For UNIX machines
Follow these instructions to install C-MOLD on the following hardware platforms:
• • • • • •

DEC Alpha AXP, Digital UNIX v4.0 HP 9000, HP-UX 10.20 IBM, AIX 4.2 SGI (MIPS I), IRIX 5.3 SGI (MIPS IV), IRIX 6.2 Sun SPARC, Solaris 2.5 (SunOS 5.5)

SGI users should install the MIPS IV version only on a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir 4 Type cd cdrom_dir 5 For all but HP computers, type ./install, and follow the on-screen instructions. HP: type ./INSTALL.\;1

For Windows NT 4.0 and 95 machines
Follow these instructions to install C-MOLD on the following hardware platforms:

• • •

PC 486, Pentium, or Pentium Pro, Windows 95 PC Pentium or Pentium Pro, Windows NT 4.0 DEC Alpha AXP NT, Windows NT 4.0

1 Intel CPU: locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. DEC Alpha AXP CPU: locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. (where xxx corresponds to the particular release you are installing) 2 Run setup.exe.

Enhancements in C-MOLD Cooling simulation.
An enhanced version of C-MOLD Cooling is included in this incremental release, which was first introduced in the 98.5 incremental release. These release notes give more detail about the changes that were implemented and what users can expect when they use the new C-MOLD Cooling. The enhanced C-MOLD Cooling includes two significant improvements compared to earlier versions: the problem of overlapping cooling channel elements has been overcome, and the speed of the simulation is much faster.

No more overlapping cooling channel elements.
When a bend occurs in a cooling channel, it is possible for the channel elements to overlap in the model of the cooling system. This overlap may cause problems in the numerical simulation. To overcome such problems, in previous versions of C-MOLD Cooling, the channel elements were treated as disconnected, and related elements were shortened or ignored to minimize the effect of the overlap. This treatment, however, also introduced some error in the solution, because the temperature and heat flux calculations could not vary continuously along the disconnected channel elements, as shown in Figure 1. In the enhanced C-MOLD Cooling (98.5 and later releases), a new model is used to deal with cooling channel elements, and it is no longer necessary to disconnect the channel elements to avoid overlap. Thus all physical parameters can vary continuously along the cooling channels (see Figure 2), and the accuracy of simulation is improved.

Figure 1. Cooling channel efficiency results from the old C-MOLD Cooling. The disconnected elements and the discontinuous results at the bends in the channel are easily seen.

Figure 2. Improved cooling channel efficiency results from the enhanced CMOLD Cooling (version 98.5 and later). The results are continuous along the entire length of the channel.

Faster running speed:
The boundary element method (BEM) is used in mold cooling simulation, which relies on a system of equations. Since the related matrix is full and very large, it is very timeconsuming to solve this system of equations directly; instead, an iterative solution method is used. In an iterative method, there are three key factors:
•

•

•

Initial solution: this is an assumption of the value of the real solution, which is used as the starting point for the iterations. How good the assumption is (how close the assumed value is to the real value) directly affects the running time required to complete the simulation. Solver: this refers to the specific iterative technique that is used, for example, the Gauss-Seidel solver, CG solver, and so on. The solver determines the convergence rate of the solution. Convergence criterion: this specifies the acceptable level of approximation allowed between iterations in solving the system of equations.

In the enhanced C-MOLD Cooling, all of these key factors have been changed. A new initial solution and a new solver are employed, which make the enhanced C-MOLD Cooling run much faster than older versions. In addition, a new convergence criterion is used. A solution is considered to be converged when the residual is small enough. In a matrix equation [A][x]=[b], the residual is defined as [R]=[A][x]-[b], which is the accuracy of the solution. In older versions of C-MOLD Cooling, because of a technical difficulty, an indirect method other than the residual, was used as the convergence parameter. This indirect method checked the change in the solution value from one iteration to the next, and if the change was less than the

convergence criterion, the solution was assumed to be converged. Sometimes this indirect method failed to reflect the real convergence approximation. In the enhanced C-MOLD Cooling, since the storage of BEM elements has been improved, the former technical difficulty is also solved, and it has become possible to use the residual directly as convergence parameter, which eliminates a source of error that occurred in the older version.

Impact on solution accuracy:
In some cases, it is possible that the enhanced C-MOLD Cooling (version 98.5 and later) and older versions would result in different solutions. To determine which is the more accurate solution, just compare the residuals. The enhanced C-MOLD Cooling uses the residual as the convergence parameter. While the old C-MOLD Cooling also gives the residual, but it is not used as the convergence parameter. The result with the smallest residual value is the more accurate solution. Using the enhanced C-MOLD Cooling will always require fewer iterations to reach the solution than were required with the old version, and in addition, the results of the enhanced C-MOLD Cooling are often more accurate as well. For example, compare these results of the enhanced C-MOLD Cooling and the older version when the simulation is run on a simple rectangular plate with the convergence criterion specified as 0.001: Enhanced C-MOLD Cooling (98.5 and later) first iteration convergence parameter last iteration convergence parameter number of iterations residual after last iteration mold wall temperature range temperature difference range 1.1618E-01 % 7.0136E-04 % 6 7.0136E-06
(same as last iteration convergence parameter, above)

Old C-MOLD Cooling (98.4 and earlier) 3.4129E+00 % 9.9572E-04 % 35 2.8376E-05 27.25 - 49.75 8.14 - 22.49

29.05 - 51.35 8.04 - 21.93

This example clearly shows us why the enhanced C-MOLD Cooling runs faster. It can also be seen that in the old C-MOLD Cooling, the residual after the last iteration is much larger than the convergence parameter in the last iteration. However, in the enhanced C-MOLD Cooling, these values are the same, so the convergence parameter becomes a true measure of the solution accuracy.

Known problems in this release.

On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the Save Design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection, either Run Now, Run as Batch, or Cancel will be processed. The workaround is to save your design before entering the Design Diagnostics dialog.

Resin database changes.
Please refer to the Search the C-MOLD Resin Database page on C-MOLD's Web site to see what data is available.

C-MOLD 98.5 Release Notes
The C-MOLD 98.5 incremental release.
The 98.5 release of C-MOLD is an incremental release. Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features for you. Our last general release to all customers with current Support & Update agreements was made in November 1997. These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office.

Supported platforms.
The current release supports the hardware platform and operating system configurations given in the table below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. Hardware Platform DEC Alpha AXP DEC Alpha AXP NT HP 9000 IBM Intel-based PC 486, Pentium or Pentium Pro Intel-based PC Pentium or Pentium Pro SGI (MIPS I) SGI (MIPS IV) Sun SPARC Minimum C-MOLD OS Level Digital UNIX 4.0 Windows NT 4.0 HP-UX 10.20 AIX 4.2 Windows 95 Windows NT 4.0 IRIX 5.3 IRIX 6.2 Solaris 2.5 (SunOS 5.5)

Installation procedure.
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or install CMOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator.

Refer to the C-MOLD System Administrator Guide for setting up special configurations and/or troubleshooting system problems. It was distributed in hard copy form with the CMOLD 98.1 general release and is available on-line in HTML format from the documentation screens. Type cmdoc once C-MOLD is installed to access the on-line documentation set.

For UNIX machines
Follow these instructions to install C-MOLD on the following hardware platforms:
• • • • • •

DEC Alpha AXP, Digital UNIX v4.0 HP 9000, HP-UX 10.20 IBM, AIX 4.2 SGI (MIPS I), IRIX 5.3 SGI (MIPS IV), IRIX 6.2 Sun SPARC, Solaris 2.5 (SunOS 5.5)

SGI users should install the MIPS IV version only on a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir 4 Type cd cdrom_dir. 5 For all but HP computers, type ./install, and follow the on-screen instructions. HP: type ./INSTALL\;.

For Windows NT 4.0 and 95 machines
Follow these instructions to install C-MOLD on the following hardware platforms:

• • •

PC 486, Pentium, or Pentium Pro, Windows 95 PC Pentium or Pentium Pro, Windows NT 4.0 DEC Alpha AXP NT, Windows NT 4.0

1 Intel CPU: locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. DEC Alpha AXP CPU: locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. (where xxx corresponds to the particular release you are installing) 2 Run setup.exe.

Enhancements introduced in this release.
C-MOLD Interactive Modules
On HP computers, C-MOLD interactive modules now require X11 R6 run-time environment software. Previous versions required R4 or R5.

C-MOLD Cooling
A new representation is used for cooling-channel elements, which eliminates overlap problems that could occur in previous releases at bends in cooling channels. CPU time required to complete Cooling simulation on a mid-sized model has been reduced significantly. In addition, users are no longer required to adjust the relaxation number, and the solution now is more robust.

C-MOLD Coolant Flow
The output format of pressure drop in cooling manifold has been changed. The change will affect the display of coolant pressure drop only at junctions of regular cooling channels with baffles or bubblers. In modeling, a baffle or bubbler is defined by at least two nodes: one for the coolant entrance, and the other for the free end where the coolant changes direction (see Figure 329 and Figure 3-30 in the C-MOLD Modeler & Visualizer User's Guide for details).

Figure 1. Model representation of baffle or bubbler. It is obvious that at the entrance node, the pressure is discontinuous at the two sides of the baffle plate or bubbler plate. Therefore, an abrupt change of pressure at the entrance node should be seen in the graphical display. In the baffle or bubbler, however, the pressure drop of entering flow and returning flow is still displayed on the element(s) from the entrance node to the free-end node. In other words, after the code change, the coolant pressure at the free-end node should be the same as the coolant pressure at the entrance node from the exit side of the baffle or bubbler. This change has no effects on results of C-MOLD Cooling simulation. Figure 2 and Figure 3 show the displays of coolant pressure before and after the code change, respectively.

Figure 1. (Click to zoom in.) Coolant pressure Figure 2. (Click to zoom in.) Improved coolant display before the code change. pressure display after the code change.

C-MOLD Integrated Shrinkage & Warpage Update: Layer-based Residual Stress Coupling with Fiber Orientation
    

Terminology Coupling with Fiber Orientation Layer-Based Information vs. Equivalent Loadings Technical Details How to Use the New Feature

What is new
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• • •

The Fiber Orientation option for Integrated Shrinkage & Warpage simulation gives improved deformation result compared to previous versions, because of the coupling of the residual-stress and thermo-mechanical properties calculations with the fiber-orientation calculation. The interface between C-MOLD Residual Stress and C-MOLD Shrinkage & Warpage is now layer-based, which is different from the equivalent loadings used by previous versions. The number of layers used for the Residual Stress calculation is the same as the number of layers specified for Filling & Post-Filling simulation. The molded-in residual stress after part ejection is now optional output as requested by users, instead of in-cavity residual stress. C-MOLD Polymer Laboratory now provides fast-cooling pvT testing for semicrystalline materials. Shrinkage & Warpage predictions can be improved to within 10% accuracy by using the fast-cooling pvT data.

Terminology
What is in-cavity residual stress? The in-cavity residual stress refers to the internal stress accumulated during the solidification of the part inside the cavity until the temperature and pressure within the cavity drop to ambient conditions. This in-cavity residual stress is the driving force of part shrinkage and warpage after ejection. It is calculated by C-MOLD Residual Stress and stored in the interface file to C-MOLD Shrinkage & Warpage (filename.ppt). In-cavity residual stress cannot be measured on a molded part because of the stress relaxation that occurs after ejection. What is molded-in residual stress? After part ejection, the constraints from the mold cavity are released, and the part is free to shrink and deform. After it settles to an equilibrium shape, the remaining stress inside the part is called molded-in residual stress, or simply, residual stress. The difference between in-cavity residual stress and molded-in residual stress is whether or not the constraints imposed by the cavity on the part have been released. Molded-in residual stress can be measured on a molded part. This new release of C-MOLD includes the option to output the molded-in residual stress. Why Integrated Shrinkage & Warpage? The predicted final deformation of a part after ejection is what a user expects a simulation to produce. The intermediate, in-cavity residual stress has no practical application for users, and therefore, it no longer included in C-MOLD output file. C-MOLD Residual Stress and C-MOLD Shrinkage & Warpage are now tightly integrated with layer-based residual stress and mechanical properties calculations;

this feature is not provided with interfaces to other, general-purpose structural analysis programs. Why fast-cooling pvT? The physical properties of semi-crystalline materials (such as PET, PBT, Nylon, etc.) depend on the degree of crystallinity. During the injection molding process, the material's crystallinity depends on several processing parameters, especially on the cooling rate. Conventional pvT testing is based on measurements at equilibrium or at a very slow cooling rate. The pvT behavior of semi-crystalline materials can be quite different under a fast cooling rate, therefore resulting in different amounts of shrinkage. C-MOLD recently developed a technique to measure and predict pvT under the fast-cooling conditions similar to an injection molding process. It has been verified by the Polymers Department of the GM Research and Development Center (under NIST/TED project) that fast-cooling pvT data in the simulation can improve the shrinkage prediction to within 10% accuracy for semi-crystalline materials. C-MOLD Polymer Laboratory offers the fast-cooling pvT material testing service. Check with your resin suppliers or C-MOLD Polymer Laboratory for details.

Residual Stress and Thermo-Mechanical Properties Calculations Coupled with Fiber Orientation Calculation
Previous versions of C-MOLD used the thermo-mechanical properties in the flow and transverse directions for the Shrinkage & Warpage calculations. In cases where the material is fiber-reinforced, the local thermo-mechanical properties would depend on the fiber orientation. This new version of C-MOLD calculates the local thermo-mechanical properties based on predicted fiber orientation, and the local residual stress corresponds to the local thermomechanical properties. For fiber-reinforced materials, the Shrinkage & Warpage predictions are now based on the residual stress and thermo-mechanical properties coupled with fiber orientation prediction. Users can add a service-loading simulation after the residual-stress calculation in order to predict part performance under service. The influence of fiber orientation and molded-in residual stress can be considered in the structural design of plastic parts.

Layer-Based Information vs. Equivalent Loadings
In previous versions of C-MOLD Residual Stress, equivalent loadings were output into the interface file and used for Shrinkage & Warpage calculation. Equivalent loadings were calculated for each node and element based on in-cavity residual stress that was distributed over thickness.

Such equivalent loadings are self-balanced before part deformation, but can become unbalanced after large deformation, resulting in a rigid-body motion to the Shrinkage & Warpage prediction. After the introducing geometric non-linear analysis in C-MOLD Shrinkage & Warpage, it became possible to calculate large deformations. When this happens, the originally balanced equivalent loadings may become unbalanced. It is not possible to perform a geometric non-linear Shrinkage & Warpage simulation with equivalent loadings based on in-cavity residual stress. The in-cavity residual stress should be used directly, because it is always self-balanced, no matter how the part is deformed. Incavity residual stress is used for Shrinkage & Warpage prediction in this update. In-cavity residual stress is predicted for each layer of each element. In previous versions of C-MOLD Residual Stress, a part was assumed homogeneous, which means that thermo-mechanical properties (isotropic or transversely isotropic) are uniformly distributed. In this update, this assumption is no longer valid for fiber-filled composites; that is, layer-based thermo-mechanical properties are calculated for each layer of each element and used for Shrinkage & Warpage calculation. The layer-based information mentioned above is stored in filename.ppt, and used as input to the final Shrinkage & Warpage prediction.

Technical Enhancements
These technical explanations of differences from previous versions are provided for reference. Users do not have to know these details to run the new version.
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The micromechanics model used is now the Tandon-Weng model, instead of the Halpin-Hsai model that has been used in previous versions. Results of the NIST/TED project suggested that the Tandon-Weng model would give slightly better predictions; however, the improvement is marginal. Micromechanics is a way of studying a composite material on a very localized scale with extreme orientations, such as the perfectly aligned case. In calculating average orientation, orthotropic closure is now used instead of hybrid closure, which has been used in previous versions. This change also resulted from work under the NIST/TED project. Closure approximation adds an extra equation or equation group to complete the equation group for fiber orientation. Without it, the number of unknowns are more than the number of equations, so there would be no way to solve the equations. Closure approximation may not be based on physics. Orthotropic closure is derived to agree with analytical solutions in extreme orientation states. In C-MOLD Fiber Orientation, the optimized quasi-planar (OQP) method is now used instead of the quasi-planar (QP) method that has been used in previous versions. The OQP method was derived by Professor Charles Tucker under the NIST/TED project. Tests from GM Research and Development Center indicate that

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the OQP method gives orientation results that are closer to measured orientation values. In C-MOLD Residual Stress, the instant freeze model is now used instead of the thermo-rheological simple viscoelastic model that has been used in previous versions. This change has been implemented because few users employed the relaxation moduli in the thermo-rheological simple viscoelastic model available in previous C-MOLD Residual Stress versions. In the previous implementation, elastic models could be considered as subsets of the thermo-rheological simple viscoelastic model; but it took more CPU time and memory, and when elastic constants were used, it essentially performed as an instant-freeze model. The instant freeze model assumes that the polymer or polymer composite will become elastic immediately after the temperature drops below the transition temperature. In contrast, the thermo-rheological simple viscoelastic model assumes that the material gradually gains strength based on temperature and time change after the temperature drops below the transition temperature. The temperature and time can be superposed into a material time, and the relaxation moduli as functions of the material time can then be used in the residual-stress calculation.

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Fiber-filled composite materials now are assumed to be orthotropic instead of transversely isotropic, which has been assumed in previous versions. This means that E33 (elastic modulus in the thickness direction) is no longer assumed equal to E22 (elastic modulus in the planar direction perpendicular to the E11 direction) for fiber-filled materials, which is a more reasonable assumption. Among all the changes, it is found that the biggest influence on the Integrated Shrinkage & Warpage result is the pvT data. For simulations of applications using semi-crystalline materials, using fast-cooling pvT data as input to the simulation will definitely yield more accurate results. This change is not to the code itself, but rather to the material data that is input to the simulation.

How to Use the New Features
All of these improvements were internal to the C-MOLD modules. From the user's point of view, there is almost no change in how to prepare for and launch the Integrated Shrinkage & Warpage simulation.
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T-CODE 00614 and T-CODE 00615 have been added to the parameter file (filename.par) to control the various layer-based stress outputs. Most of these stresses are useful only to analysts. The amount of data can be large because stress data is stored for each element and each layer. These T-CODEs are used by CMOLD Shrinkage & Warpage module only. T-CODE 00615 is used only when service loadings are defined.
T-CODE# Equation: Units: 00614 NONE NONE

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• • • • • • • • • • • • • • • • • • • • • • •

Range: Default Value: Option output Option Option Option T-CODE# Equation: Units:

0-4 0 no molded-in stress output 1 for Principal Residual Stress (Molded-in) 2 for option 1 plus Max Shear Stress 3 for option 1 plus Mises-Hencky Stress 4 for all the stress outputs 00615 NONE NONE

Range: 0-4 Default Value: 0 no stress output for service loading and combined with service loading Option 1 for Principal Residual Stress (service) and (molded-in + service) output Option 2 for option 1 plus Max Shear Stress Option 3 for option 1 plus Mises-Hencky Stress Option 4 for all the stress outputs

• •

The interface to ABAQUS from C-MOLD Residual Stress is temporarily suspended, beginning with this 98.5 incremental release. The layer-based in-cavity residual stresses and/or thermo-mechanical properties are stored in an ASCII interface file called filename.ppt, which is in C-MOLD output file format. Translation from this file to an equivalent input file to any other structural analysis package capable of doing layer-based shell analysis is possible by anybody who knows both file formats. All the T-CODE's involved for geometric non-linearity calculation in C-MOLD Shrinkage & Warpage are still effective. To get fast-cooling pvT data requires additional material testing and data reduction. Data has been generated for only a handful of resins so far. Due to the limited number of tested resins, at this time, the fast cooling pvT data is not included in the C-MOLD Database that is released to customers. Contact your resin suppliers or CMOLD Polymer Laboratory for the data and testing services.

More Testing Required
This major update has had only limited tests so far. More tests are required, and the developers welcome any comments or reports of problems with this update.

Known problems in this release.
On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a

file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the Save Design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection, either Run Now, Run as Batch, or Cancel will be processed. The workaround is to save your design before entering the Design Diagnostics dialog.

Resin database changes.
The C-MOLD Resin Database now includes viscosity data for 4,370 resins, of which 809 have pvT data, 189 have mechanical properties data, and 325 have juncture loss data. Please refer to the Search the C-MOLD Resin Database page on C-MOLD's Web site to see what data is available.

C-MOLD 98.4 Release Notes
The C-MOLD 98.4 incremental release.
The 98.4 release of C-MOLD is an incremental release. Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features for you. Our last general release to all customers with current Support & Update agreements was made in November 1997. These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office.

Supported platforms.
The current release supports the hardware platform and operating system configurations given in the table below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. Hardware Platform DEC AXP DEC AXP NT HP 9000 IBM Intel PC SGI
(MIPS I and MIPS IV)

Current C-MOLD OS Levels Digital UNIX 4.0 Windows NT 4.0 HP-UX 10.20 AIX 4.2 Windows 95 Windows NT 4.0 IRIX 5.3 IRIX 6.2 for MIPS IV version Solaris 2.5

Sun SPARC

Installation procedure.
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD 98 without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or install C-MOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator.

Refer to the C-MOLD System Administrator Guide for setting up special configurations and/or troubleshooting system problems. It is available in HTML format on the CD, from our web site www.cmold.com or in hard copy format. A printed copy was included with the last general release.

For UNIX machines
SGI users should install the MIPS IV version only if they are using a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. Typically, newer versions of operating systems are upward compatible. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. 4 Type cd cdrom_dir. 5 Type ./install, and follow the on-screen instructions. HP users will need to type ./INSTALL\;.

For Windows NT and 95 machines
Follow these instructions if you're running on Windows NT 4.0 or Windows 95.
•

Intel CPU 1 Locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. 2 Run setup.exe

•

Alpha AXP CPU 1 Locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. 2 Run setup.exe

Enhancements Introduced in this Release
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C-MOLD Filling and Post-Filling o The clamp force prediction at the end of filling, in the case of an incompressible material, is modified to calculate using the final pressure distribution at the instant before complete fill. This reduces the clamp force prediction because otherwise, the incompressible material assumption would propagate the entrance pressure through out the cavity. Normally pvT data is used and compressible behavior of the polymer is accounted for. You can force the program to use incompressible density model by manually adjusting the material input file. o If the input melt temperature is less than the material's transition temperature, error message 99621 is displayed and execution stops. If the input melt temperature is less than b5 of the pvT model, a warning message is issued and the program continues to calculate. Note that normally using a melt temperature near the transition temperature or b5 does not match the physical processing conditions and indicates either a problem in the material selection or data or the processing conditions.

Problems fixed in this Release
•

C-MOLD Gas Assisted injection molding o When the pre-set post-filling time is exceeded, output follows the normal short-shot procedure instead of stopping immediately. This provides melt front advancement information up to the short-shot to be viewed.

Known Problems in this Release
•

On Windows and using Exceed 5.1.1 the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the design diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the design diagnostics dialog will remain on top of the save design selection dialog. In order to save the design you need to dismiss the design diagnostics dialog. Even though you dismiss the design diagnostics dialog your selection, either "Run Now", "Run as Batch", or "Cancel" will be processed. The work around is to save your design before entering the design diagnostics dialog.

Material Database Changes
Please refer to the Search the C-MOLD Material Database Internet web page to see what data is available.

Copyright 1998 Advanced CAE Technology, Inc. All Rights Reserved.

C-MOLD 98.3 Release Notes
The C-MOLD 98.3 incremental release.
The 98.3 release of C-MOLD is an incremental release. Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features for you. Our last general release to all customers with current Support & Update agreements was made in November 1997. These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office.

Supported platforms.
The current release supports the hardware platform and operating system configurations given in the table below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. Hardware Platform DEC AXP DEC AXP NT HP 9000 IBM Intel PC SGI
(MIPS I and MIPS IV)

Current C-MOLD OS Levels Digital UNIX 4.0 Windows NT 4.0 HP-UX 10.20 AIX 4.2 Windows 95 Windows NT 4.0 IRIX 5.3 IRIX 6.2 for MIPS IV version Solaris 2.5

Sun SPARC

Installation procedure.
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD 98 without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or install C-MOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator.

Refer to the C-MOLD System Administrator Guide for setting up special configurations and/or troubleshooting system problems. It is available in HTML format on the CD, from our web site www.cmold.com or in hard copy format. A printed copy was included with the last general release.

For UNIX machines
SGI users should install the MIPS IV version only if they are using a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. Typically, newer versions of operating systems are upward compatible. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. 4 Type cd cdrom_dir. 5 Type ./install, and follow the on-screen instructions. HP users will need to type ./INSTALL\;.

For Windows NT and 95 machines
Follow these instructions if you're running on Windows NT 4.0 or Windows 95.
•

•

Intel CPU 1 Locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. 2 Run setup.exe Alpha AXP CPU 1 Locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. 2 Run setup.exe

Enhancements Introduced in this Release

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•

•

C-MOLD Filling and Post-Filling Based on a user request, allowance for negative coefficient of thermal expansion for fiber filled materials has been added. C-MOLD Filling/EZ A suggested ram speed profile is one of the outputs from C-MOLD Filling/EZ. Using the suggested ram speed profile will keep melt front speeds more uniform, resulting in a molded part with less molded in stresses. Ram speed profile settings are provided for the number of settings provided in the process conditions. Previously, if you only had 2 settings, say at 0% of stroke and 100% of stroke for example, only 2 suggested settings would be output. On user request we've changed the program to output 11 settings if only 2 settings are input. New Visualizer prototype o Reduction of the amount of memory usage during animation by using temporary disk files improves performance on systems with limited amounts of available RAM. o A wider variety of OpenGL terminals are now supported. The new visualizer prototype can be started once the C-MOLD environment has been established by typing cviz97 in a console window.

Problems fixed in this Release
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New Visualizer prototype o Workarounds for light shading problems on Solaris and Digital UNIX implementations of OpenGL have been added. The OpenGL driver automatically determines if the workaround is necessary and implements it without any changes required by you. o Some implementations of OpenGL do not properly implement GL pixmaps which may cause a problem when saving the screen image to a TIF file for printing. You can use the CMOLD_GP_PRINT_USE_SCREEN environment variable to bypass use of the GL pixmaps. Just set this variable to 1 before starting the Visualizer.

Known Problems in this Release
•

On Windows and using Exceed 5.1.1 the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the design diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the design diagnostics dialog will remain on top of the save design selection dialog. In order to save the design you need to dismiss the design diagnostics dialog. Even though you dismiss the design diagnostics dialog your selection, either "Run Now", "Run as Batch", or "Cancel" will be processed. The work around is to save your design before entering the design diagnostics dialog.

Material Database Changes
Please refer to the Search the C-MOLD Material Database Internet web page to see what data is available.

Copyright 1997 Advanced CAE Technology, Inc. All Rights Reserved.

C-MOLD 98.2 Release Notes
The C-MOLD 98.2 incremental release.
The 98.2 release of C-MOLD is an incremental release. Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features for you. Our last general release to all customers with current Support & Update agreements was made in November 1997. These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office.

Installation procedure
This release uses the same interactive procedure as C-MOLD 98.1 that guides you through the installation process. Most users will be able to install C-MOLD without system administrator assistance in less than ten minutes. You might need superuser privileges in order to mount the CD or install C-MOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator. The information-packed C-MOLD System Administrator Guide is intended for use by your system administrator for setting up special configurations and/or troubleshooting system problems. It was distributed in hard copy form with the C-MOLD 98.1 general release and is available online in HTML format from the documentation screens. Type cmdoc once CMOLD is installed to access the online documentation set.

For UNIX machines
These instructions will work for the following hardware platforms: HP 9000 HP-UX 10.20, DEC Digital UNIX v4.0, IBM RS6000 AIX 4.2, Sun SPARC Solaris 2.5, and SGI IRIX 5.3 (MIPS 1) and SGI IRIX 6.2 (MIPS IV). SGI users should install the MIPS IV version only if they are using a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit depending on your hardware configuration. DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration.

IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. 4 Type cd cdrom_dir. 5 Type install, and follow the on-screen instructions.

For Windows NT 4.0 and 95 machines
Follow these instructions if you're running on Windows NT 4.0 or Windows 95. 1 If running on an Intel based PC, locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. 2 If running on a DEC Alpha AXP based machine, locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. 3 Run setup.exe.

Changes since C-MOLD 98.1
The Windows 95/NT C-MOLD 98.2 incremental release supports Exceed 6. Changes in the location of locale information between Exceed 5 and 6 require a patch for earlier versions of C-MOLD. Contact your local C-MOLD office for information about obtaining the patch if you are running an earlier version of C-MOLD and Exceed 6. This incremental release has no other significant changes to formal C-MOLD products since C-MOLD 98.1. Included on the C-MOLD 98.2 CD is a copy of the new visualizer prototype which demonstrates the look and feel of our upcoming user interface design. UNIX users with an OpenGL capable workstation can type cviz97 at the command prompt to start the prototype visualizer. HP and Windows versions of the visualizer are not yet available but are planned for a future release. To try it out, navigate to a directory containing C-MOLD results and experiment with the new visualizer. We'd like to hear your comments about it.

Copyright 1997 Advanced CAE Technology, Inc. All Rights Reserved.

Release Notes 98.1 Introduction
In addition to twice-yearly general releases, our monthly incremental releases provide for timely problem corrections and the implementation of new features. When applicable, the incremental release version of a fix or enhancement is noted in the monthly summaries. For information on obtaining the latest monthly incremental release, contact your local CMOLD office. The C-MOLD web page is also a good place to look for the latest information about our products. Table 1 lists the enhancements to and problems fixed in this latest general release of CMOLD, and gives the incremental version of the software in which the change was introduced. TABLE 1. Summary of changes to C-MOLD products in release 98.1 Introduced C-MOLD productµ Enhancement/problem fixedµ in releaseµ C-MOLD License Losing IGES interface licensesµ 97.8µ Managerµ Setting the non-linear analysis option for Shrinkage Control Panelµ 97.10µ & Warpage directly from Control Panelµ Coolant Flowµ Correction in the heat loss calculationµ 97.11µ Output data sets addedµ 97.8µ Multiple gas-injection sitesµ 97.12µ Pre-filled polymer volume fractionµ 97.8µ Material compressibility during fillingµ 97.8µ Gas-Assisted Injection Full pvT modeling for both filling and post-filling Moldingµ 97.8µ stagesµ Program stop time consistent with PMA analysisµ 97.8µ Maximum # of elements µ 97.10µ Entrance nodes on connectorsµ 97.10µ Injection Compression Predicted clamp forceµ 97.11µ Moldingµ Microchip Floating point numbersµ 97.9µ Encapsulationµ Maximum pressure differenceµ 97.9µ Wire-sweep and paddle-shift analysesµ 97.10µ

Memory allocationµ Reactive Molding enhancementsµ Shrinkage and Warpage Geometric linear vs. non-linear deformationsµ Analysisµ Patranµ µ Ansysµ IDEASµ Weldlines and Air Improved usability and maintainabilityµ Trapsµ Material Databaseµ Specific heat datasetsµ

97.8µ 97.8µ 97.8µ 97.9µ 97.11µ 97.12µ 97.8µ 97.10µ

Running C-MOLD
It is now possible to operate in the root directory. While uncommon for UNIX users, some Windows users might want to start in the root directory.

Keyfiles
As long as your Support & Update agreement is current and you are updating from a 96.7 or higher version, your existing keyfile will enable this release. If you are updating directly to the 98.1 release from a version of C-MOLD earlier that 96.7, you will need a new keyfile. If using your existing keyfile with the 98.1 release results in an Inconsistent encryption code error, contact your local C-MOLD office to obtain your new keyfile. You can check your C-MOLD license key for the recorded Support & Update expiration date. Find the line with the key for C-MOLD that looks like this:
2eac 4f4a 8ah6 8d74 23d6 28gf d373 6k93 cmold NO EXPIRY 12/01/96 15users

The date in mm/dd/yy format is your Support & Update expiration date. To run version 98.1, this date must be after 03/31/97. If you have a question about your Support & Update agreement, please call your local C-MOLD office.

Installation procedure
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD 98 without system administrator assistance in less than ten minutes. See the inside cover of your CD case for complete installation instructions.

You can also install C-MOLD and work in folders whose names contain spaces. This is available on both the UNIX and Windows version, although spaces in directory and filenames are more common in Windows than in UNIX.

C-MOLD License Manager
We've fixed a problem manifested by losing IGES interface licenses over time when the license manager was running on an IBM workstation.

Supported platforms
The current release supports the hardware platform and operating system configurations given in the table below. We routinely review this list as part of our semi-annual software update schedule and will periodically make adjustments to reflect available and popular platforms. With the C-MOLD 98.1 release, we're changing our supported configurations. These and the C-MOLD 98.1 operating system requirements are given in the table below. We began implementing these changes with the C-MOLD 97.8 incremental release. TABLE 2. Supported platforms Hardware Platformµ C-MOLD Minimum OS Levelµ PC 486, Pentium, or Pentium Proµ Windows 95µ PC Pentium or Pentium Proµ Windows NT 4.0 (or higher)µ DEC Alpha AXPµ Windows NT 4.0µ DEC Alpha AXPµ Digital UNIX 4.0 (or higher)µ HP 9000/700µ HP-UX 10.20 (or higher)µ IBM RS/6000µ AIX 4.2 (or higher)µ SGIµ IRIX 5.3 (or higher)µ SGI (MIPS IV)µ IRIX 6.2 (or higher)µ Sun SPARCµ Solaris 2.5 (SunOS 5.5) (or higher)µ

Control Panel
To boost performance, files from the temporary run directory are now moved to the design directory instead of copying them. This saves both time and disk space.

Setting the non-linear analysis option for Shrinkage & Warpage

You can now set the controls for non-linear analysis in Shrinkage & Warpage directly from the user interface. Go to the Analysis Parameters file in the Design Diagnostics dialog to edit the Option for non-linear warpage analysis, specifying the maximum number of iterations.

Coolant Flow
We made a correction in the heat loss calculation at the juncture between a regular cooling channel and a bubbler or baffle. The change is noticed only in a small set of modeling cases.

Filling & Post-Filling
It is now possible to pre-pack the main cavity before opening a valve gate to an overflow area.

Gas-Assisted Injection Molding
The enhancements to C-MOLD Gas-Assisted Injection Molding simulation further improve simulation results and provide more useful features to C-MOLD customers. The program is built on top of the same framework on which C-MOLD Filling & Post-Filling simulations are based. As a result, you can expect consistent results from this release for polymer filling and packing stages as well as gas-assisted stages. Some of the new features in this release are:
• • • • • •

Preliminary packing before gas injection in post-filling stage Valve-gate opening and closing Dynamic memory allocation Conjugate-Gradient (CG) solver for pressure solution Error/Warning messages in text report output Text report on post-filling

Output data sets
The following table shows the changes made to the output data sets in the 98.1 release of Gas-Assisted Injection Molding simulation. The shaded entries are those that have been removed since the last general release; the rest are new. TABLE 3. Output data set changes Data setµ Data typeµ Data categoryµ Skin-polymer half-gap thickness (top)µ Elementµ Designµ Skin-polymer half-gap thickness (bottom)µ Elementµ Designµ

Volumetric shrinkageµ Frozen-in shear stressµ Melt front speedµ Recommend ram-speedµ Percentage fillµ Melt front velocityµ Total design weightµ Average flow lengthµ Error/Warning messagesµ Report on post-fillingµ

Elementµ Elementµ Elementµ Scalarµ Scalarµ Scalarµ Scalarµ Scalarµ Textµ Textµ

Design (post-filling)µ Detailµ End of fillingµ Designµ Designµ Designµ Designµ Designµ Summary reportµ Summary reportµ

Multiple gas-injection sites
Support for multiple gas-injection control was added in the new release. This enhancement allows you to simulate the injection of gas at multiple locations with independent gasinjection controls-that is, each gas-injection point has its own control, including timing and profiling. The current implementation even permits using both gas-pressure control (process that controls the gas pressure and its profile) and gas-volume control (process that compresses pre-charged gas in a compression cylinder) at different gas-injection points within the same part. Additional information is available in New Multiple Gas-Injection Control Feature.

Pre-filled polymer volume fraction
A new concept of "pre-filled polymer volume percentage" has been introduced. Releases earlier than 97.7 treat the polymer melt as an incompressible fluid during the filling stage. As a result, with a constant Ram speed profile (rel), the ratio of Resin injection time to Fill time is the volume-filled percent before gas injection. For example, the process conditions file shown, in part, in Figure 1 will lead to a pre-filled polymer volume of 95% (i.e., 1.9/2.0) at the time of gas injection. Figure 1 Process conditions file (partial) from version 97.7
PROC 1 15 10100 10101 10602 50 50 50 10 30 50 Description of TCODE .... 1 Fill time 2.0 1 Resin injection time 1.9 22 Ram speed profile (rel) 0 50 20 50 40 50

60 50 50 50 70 90 10103 10200 injection 50 50 1 1 80 100 Gas injection time 1.5 Timer for core or gas 1.9

There are two deficiencies with the previous implementation. First of all, the polymer melt actually is compressible even during filling. Second, with a variable ram speed profile, it becomes difficult to specify the resin injection time that delivers a known pre-filled polymer volume percentage. In order to handle the cases for which the pre-filled polymer volume percentage is known before the injection of gas, an input variable designated to Pre-filled polymer volume % has been introduced. In the new release, the F/P switch over by % volume is used for this purpose. When used with a non-zero Timer for hold pressure, the F/P switch over by % volume serves as the fill-to-pack switch-over criterion as usual. In other words, the polymer injection will continue (under flow rate control) until F/P switch-over by % volume is completed and the pressure control takes place for the remaining process. However, if there is no Timer for hold pressure in the input file (or if the value specified is zero), then there will be no packing imposed on the polymer after the F/P switch-over point. In the present implementation, this condition triggers the closure of polymer entrances, thereby signaling the end of polymer injection. Therefore, this variable can be used as the Pre-filled polymer volume % for the Gas-Assisted Molding simulation. If there is a delay time after the polymer entrances close, the predicted pressure inside the cavity will decay, as it will in reality. On the other hand, if the gas injection defined by the Timer for core or gas injection is triggered before the completion of F/P switch over by % volume, the polymer injection will terminate and gas entrances will open at this moment, allowing gas to be injected. That is, the program recognizes only the sequential (polymer-then-gas) process. There is no need to modify the existing process conditions file. To make the transition smoother, the new release will read-in the same input files created for earlier releases (Figure 1). What it does internally is to calculate the Pre-filled polymer volume % and store it as F/P switch over by % volume based on the Fill time, Resin injection time, and Ram speed profile (rel). It will also account for a variable ram-speed profile (such as the one specified in the .prc file in Figure 2). In this case, the pre-filled polymer volume for the process conditions file is 96.53% rather than 95%, which is simply the ratio of Resin injection time to Fill time.

Figure 2 Process conditions file (partial) from new release
PROC 1 15 10100 10101 10602 10 30 50 70 90 50 90 100 100 80 10103 injection 10200 1 1 Description of TCODE .... 1 Fill time 2.00 1 Resin injection time 1.90 22 Ram speed profile (rel) 0 30 20 40 60 80 70 100 100 100

100 30 Gas injection time 1.5 Timer for core or gas 1.90

With this new option in the new release, specification of Resin injection time or F/P switch over by % volume will depend on the actual machine control. If the injection of polymer melt is controlled by a timer, then the user can still use the Resin injection time in the input file. On the other hand, if the Pre-filled polymer volume % is the known input, the user should replace Resin injection time with F/P switch over by % volume in the process conditions file. You can find out how to modify these variables in the Process Estimator User's Guide. If the original input file with Resin injection time has been specified in such a way that gives a proper pre-filled polymer volume percent, there is no need to modify the input file, since the program will do it internally.

Material compressibility during filling
There is no doubt that including material compressibility during filling will further improve the solution accuracy. This is particularly true when the injection pressure is high, the polymer temperature variation is large, or it involves a pressure decay during the delay period when the injection screw bottoms a pre-set amount of polymer into the cavity before gas injection.

Polymer flow rate
The new release computes the polymer flow rate at the polymer entrance, based on the user-specified fill time, ram-speed profile, and the cavity volume. As the pressure increases with more and more material being injected into the cavity, the volumetric flow rate at the polymer melt fronts is typically smaller than at the polymer entrance due to material compressibility. This results in a longer actual fill time than the user-specified fill timewith a typical difference of about 5%, depending on how the material is being compressed.

For example, if the user specifies a fill time of 2 seconds, the cavity will fill in around 2.1 seconds.

Polymer injection time
The material compressibility also affects the time it takes to inject a pre-set amount of polymer into the cavity. For example, let us look at the behavior of the previous and new releases using the process conditions file shown in Figure 1. Note that the gas will be injected 1.9 seconds into the process. With the previous release, resin injection will complete in 1.9 seconds-the same time gas injection begins. Because of the incompressible approximation, the pre-filled polymer volume will be 95% (see the screen message in Figure 3, below). Figure 3 Screen message with the previous release
At time = 1.9000E+00 sec, 95.00 % of volume filled, entrance pressure = 3.2098E+07 Pa, total clamp force = 2.3281E+05 N, filling under ram speed control. 1.9010E+00 sec, 95.05 % of volume filled, resin injection completed 1.9010E+00 sec, 95.05 % of volume filled, gas injection triggered by timer. 2.0260E+00 sec, 95.51 % of volume filled, entrance pressure = 5.0000E+06 Pa, total clamp force = 3.6174E+04 N, filling under gas pressure control.

At time = At time = At time =

On the other hand, the new release will try to inject 95% of the polymer into the cavity. However, after 1.9 seconds have elapsed, the polymer injection will be terminated with a warning due to the onset of gas injection, leading to 94.386% of the polymer in the cavity (see Figure 4). In other words, when there's little or no delay time, the polymer injection could be cut short due to material compressibility. Figure 4 Screen message with the new release
Screen message with the new release (97.8): At time = 1.7674E+00 s, 8.7068E+01 % of volume filled, entrance pressure = 2.8744E+07 Pa, total clamp force = 1.9252E+05 N, filling under ram speed control. ** WARNING ** TRY TO INJECT GAS BEFORE POLYMER INJECTION STOPS. END OF POLYMER INJECTION/PACKING, POLYMER ENTRANCE IS CLOSED. At time = 1.9173E+00 s, gas injection at entrance # 1 STARTS. At time = 1.9173E+00 s, 9.4386E+01 % of volume filled, gas entrance # 1 pressure = 5.0000E+06 Pa, total clamp force = 7.5231E+04 N, filling under gas control.

Full pvT modeling for both filling and post-filling stages

The 2-domain modified Tait polymer density model should be used instead of the isotropic thermal expansion coefficient. For a better description of material behavior with rapid temperature and pressure changes, pvT data-which are available with all the termoplastic resins in the C-MOLD material database (specific or generic)-should be used. The isotropic thermal expansion coefficient previously used by early releases of Gas-Assisted Molding will not be recognized by the new release.

Longer CPU time
Because of the more rigorous analysis, the new release requires a longer CPU time compared with earlier releases. Generally speaking, the CPU time is 20% more than regular PMA analyses without gas injection and up to 6 times longer than previous CMOLD releases, depending on the size of the models.

Program stop time consistent with PMA analysis
The program will stop at the end of Post-fill time rather than the end of Gas injection time in order to be consistent with the PMA analysis. It is not necessary, however, to specify the Post-fill time since the analysis will calculate it as follows: Post-fill time = Timer for core or gas injection + Gas injection time - Fill timeµ If the user does specify a Post-fill time in the .prc file, then the larger value will be used. The Post-fill time starts counting from the instant the cavity is filled.

Illustrative Examples
The examples illustrated here are designed to demonstrate the usage of the new release. The part geometry for the designs were provided by Chung-Yuan Christian University.

Case 1: Short-shot process
In the first example, a pre-determined amount of polymer (96%) is injected into the cavity before the gas injection time of 1.75 seconds. The time it takes to fill the entire cavity with polymer is 1.6 seconds. As discussed above, the following two process conditions files will both give a pre-filled polymer volume of 96% with the new release. However, if the ramspeed profile is not constant, then it will be more difficult to set the Resin injection time in the first .prc file so that 96% of polymer is injected. Figure 5 Process conditions files suitable for both previous and new releases
PROC 1 15 10100 10101 10103 Description of TCODE .... 1 Fill time 1.6 1 Resin injection time 1.536 1 Gas injection time 2.0

10200 11302 10602 50 50 50 50 50

1 1 22

Timer for core or gas injection 1.750 Gas injection control option 0 Ram speed profile (rel) 0 50 20 40 60 80 100 50 50 50 50 50

10 30 50 70 90

Figure 6 Process conditions files suitable for the new release
PROC 1 15 10100 10300 10103 10200 11302 10602 Description of TCODE .... 1 Fill time 1.6 1 F/P switch over by % volume 96 1 Gas injection time 20 1 Timer for core or gas injection 1.750 1 Gas injection control option 0 22 Ram speed profile (rel) 0 50 10 20 50 30 40 50 50 60 50 70 80 50 90 100 50

50 50 50 50 50

For the purpose of comparison, the predicted gas penetration in terms of skin polymer fraction at the end of the process using both the previous and the new releases are shown in Figures 7 and 8, respectively. When compared to actual experimental observation, the prediction from the new release, which shows no gas permeation into the thin section, is more agreeable with the actual findings. In addition, Figure 9 shows that the overall gas volume percentage (hollowed-out volume) in the cavity is near 6% of the entire volume.

Figure 7 Predicted gas penetration in terms of skin-polymer fraction at the end of the process using the previous release

Figure 8 Predicted gas penetration in terms of skin-polymer fraction at the end of the process using the new release.

Figure 9 Predicted overall gas volume percentage as a function of time using the new release.

Case 2: Full-shot process
As mentioned previously, the new release allows the cavity to be completely filled with polymer and then undergo a short packing stage before gas is injected. The user should prepare the process conditions as shown in Figure 10. Figure 10
PROC 1 17 10100 Description of TCODE .... 1 Fill time 1.6

10300 10400 10702 80 10103 10200 11302 10602 50 50 50 50 50

1 1 4 1 1 1 22

F/P switch over by % volume 99 Timer for hold pressure 1 Relative pack/hold pressure profile 0 80 100 Gas injection time 20 Timer for core or gas injection 1.750 Gas injection control option 0 Ram speed profile (rel) 0 20 40 60 80 100 50 50 50 50 50 50 10 30 50 70 90

Note that when used with a non-zero Timer for hold pressure, the F/P switch over by % volume serves as the regular fill-to-pack (flow rate control to pressure control) criterion. In other words, when the cavity is 99% filled with polymer, pressure control will take place. In this case, a pressure equal to 80% of the polymer entrance pressure (specified by the Relative pack/hold pressure profile) at the switch-over point will be used to fill and pack out the cavity until the Timer for hold pressure ends or gas is injected, whichever comes first. In this case, the cavity gets filled after 1.655 seconds, and the preliminary packing ends earlier than the specified one-second duration as the gas injection triggered after 1.750 seconds. The predicted gas penetration in terms of skin-polymer fraction at the end of post-filling and the total gas volume percentage are plotted in Figures 11 and 12, respectively. Due to pre-packing, the total gas volume percentage reduces to 3.3%. Moreover, the gas volume percentage levels-off after 12 seconds, indicating that further holding of the gas pressure will not advance the gas penetration. This is further evidenced by the predicted volumetric shrinkage of several elements in the part (see Figure 13), which levels off after 5 seconds, suggesting further packing will not reduce the volumetric shrinkage any more. The distribution of volumetric shrinkage at the end of post-filling is shown in Figure 14.

Figure 11 Predicted gas penetration in terms of skin-polymer fraction at the end of the full-shot gas injection process.

Figure 12 Predicted overall gas volume percentage as a function of time for the full-shot process.

Figure 13 Predicted volumetric shrinkage of several elements in the part.

Figure 14 Predicted volumetric shrinkage distribution at the end of post-filling.

Problems corrected in this release
The following two system updates apply to both the Gas-Assisted Injection Molding and Injection Molding modules.

Maximum # of elements
An artificial limit of 5000 for the maximum number of elements has been removed.

Entrance nodes on connectors
The program now accounts for a modeling situation in which your entrance node is defined on a connector that leads to one or more other connectors. However, you should not "isolate" nodes-including entrance nodes-by closing a valve gate, unless the node has been filled; for example, by including a runner element at the entrance, the node will become filled. Then a following valve gate defined on a connector can be closed at a later time. Closing a valve gate that causes unfilled isolated nodes to occur will cause the program to stop.

Injection Compression Molding
Predicted clamp force
We made a correction in the predicted clamp force to include 1-D elements. In the injection-compression simulation, we do not take into account compression of 1-D elements; their use in the model is discouraged for this reason. However, in models containing 1-D elements, the clamp force calculation has been revised to include the contribution from the 1-D elements. This is consistent with the Filling and Post-Filling simulations.

Microchip Encapsulation
A number of changes have been made to Microchip Encapsulation to improve its robustness and usability. Aside from the enhancements detailed in the sections below, we also changed the code to handle:
• •

Missing elements: situations where the element numbering is not continuous. Isolated nodes: previous releases required you to use the Modeler's Check Mesh function to find and delete free nodes.

Floating point numbers
We solved problems in the Windows NT and Windows 95 versions associated with threedigit representation of exponents for floating point numbers. In some files, such as the finite element mesh (.fem) file, the three-digit exponent would cause two numeric fields to "touch" each other, causing a problem when trying to read the file later on.

Maximum pressure difference
The simulation now calculates the maximum pressure difference separately in each region. In previous versions, the maximum pressure difference was calculated at the same time in every region. This caused problems when the maximum pressure difference in different regions occurred at different times. For example, in multiple-cavity system, some cavities may fill earlier than other cavities.

Wire-sweep and paddle-shift analyses
Wire-sweep and paddle-shift analyses can now be performed using C-MOLD Shrinkage & Warpage's new non-linear analysis capability. To use this option, the following TCODE in the .enc file has to be changed.
90020 2 1 Wire Deformation Calc (0:ABAQUS,1:Analytic, 2:CWARP) 0 : Use ABAQUS for paddle-shift (or wire-sweep) analysis

1 : Analytic equation for wire-sweep analysis 2 : Use non-linear C-MOLD Shrinkage & Warpage for paddle-shift (or wire-sweep) analysis

Comparisons
We performed tests and compared the results from ABAQUS and C-MOLD Shrinkage & Warpage. Paddle shift. ABAQUS and non-linear C-MOLD Shrinkage & Warpage gave similar values. Wire sweep. Two cases were used for testing. In the first case, where the wire length was about 3 mm, ABAQUS and C-MOLD Shrinkage & Warpage (linear or non-linear) gave wire sweep values in the same order of magnitude. The wire length in the second case was about 5.5 mm. In this trial, the wire sweep values from linear Shrinkage & Warpage were about 12 times bigger than those from ABAQUS. On the other hand, the non-linear Shrinkage & Warpage values were about 10 times smaller than those from ABAQUS. The small deformation from non-linear C-MOLD Shrinkage & Warpage is because it does not consider plastic deformation (unlike in ABAQUS).

Memory allocation
Version 97.8 removed the limits of design output data sets from Reactive Molding. The previous version might not have enough memory allocation for Reactive Molding output data. If there was no .os1 file and Microchip Encapsulation was launching Reactive Molding, it allowed only up to ten design output data sets from Reactive Molding. However, a problem arose if the number of design output from Reactive Molding Analysis, as specified in the parameter (.par) file, was larger than 10 (current default = 12). The workaround was (1) to run Reactive Molding to get an .os1 file first, before running Microchip Encapsulation, or (2) to specify less than ten design outputs in the .par file for Reactive Molding.

Reactive Molding enhancements

The new release does better conversions with calculated results from ABAQUS.

Wire loop geometry
This release is more robust with unusual wire loop geometry. Microchip Encapsulation expects the wedge-bonded end node (on the leadframe side) of the wire to have the smallest z-coordinate. A numerical NaN (Not a Number) problem will occur with v97.7 if other nodes along the wire happen to have smaller z-coordinates than that of the wedgebonded end node.

Representative cavity thickness
We found that many users did not specify the Representative cavity thickness (TCODE 90100) correctly. The current implementation expects the full "package" thickness; namely, the sum of the upper and lower sub-cavities, not the thickness of the sub-cavity where the wires are located. Entering the thickness of the sub-cavity will cause about a 20% error.

Nodal property label
The program used to run into difficulty if the label of the nodal property was larger than the total number of mesh elements in the .fem file. This problem typically occurred when there were a large number of wires so that the nodal properties associated with fixity of wire bonds became huge. We've fixed this problem in the new release.

Gel conversion
The new release takes gel conversion equal to 1.0. If the gel conversion was specified as 1.0 in the previous release, Reactive Molding would not output conversion layer fraction as its design output, which caused a problem with Microchip Encapsulation. The workaround was to change gel conversion in the .mtl file to 0.99.

Shrinkage and Warpage Analysis
Geometric linear vs. non-linear deformations
A geometric non-linear analysis option is now available. The C-MOLD Shrinkage & Warpage program (versions earlier than 97.7) previously assumed that only small and geometric linear part deformations occur; the program also assumed linear elastic, transversely isotropic material behavior and thin-shell modeling. Under these assumptions, any internal force on the original structure will not change its direction, and the stiffness of the original structure will not change during the deformation. However, a plastic part can undergo a large deformation after the mold is opened. Any internal force on the part could change its direction, and the stiffness of the part actually could change because of the large deformation. Therefore, the above assumptions will introduce error into the predicted results, if the actual shrinkage and warpage become large.

Accounting for geometric non-linearity releases the constraints of the small and linear deformation assumptions, and predicted results will become more accurate for molded parts that exhibit large shrinkage and warpage. The geometric non-linear analysis will handle changes in the internal stresses as well as the stiffness of each element as the part deforms during the calculation. Accounting for geometric non-linearity also gains significance in the service-loading analysis, when resulting deformation becomes large.

Differences to expect
The non-linear analysis can give a more accurate solution for large-deformation problems, but it does not mean that the predicted deformation must be larger than the results of the previous C-MOLD Shrinkage & Warpage simulation using linear assumptions. On the contrary, the non-linear analysis results in smaller predicted deformation, in most cases. The new, non-linear analysis option in C-MOLD Shrinkage & Warpage is better used for a service-loading analysis, in which the loading could result in large deformations. However, if you encounter a modeled problem that produces large linear shrinkage and warpage, using the non-linear analysis option should produce more accurate results compared to the previous C-MOLD Shrinkage & Warpage results. Using connector elements in the model introduces additional constraints on the Shrinkage & Warpage simulation because, by definition, the two connected nodes should have the same displacement values. When connectors are used in the runner system or between a runner and the cavity, they will not be included in the calculations. However, when connectors are used in modeling the part itself, the additional constraints might introduce some error, and unrealistic displacement values could be predicted by the previous CMOLD Shrinkage & Warpage program. This problem has been considered and is handled in the updated C-MOLD Shrinkage & Warpage program, such that results of the calculations now show no relative deformation between the two nodes linked by a connector element.

Using the non-linear analysis option
To use the geometric non-linear analysis option in the updated C-MOLD Shrinkage & Warpage simulation, two TCODES are introduced in the parameter file (.par):
•

•

TCODE 612 Option for non-linear warpage analysis Default = 0 (linear); 1 (non-linear) TCODE 613 Maximum number of non-linear s&w iterations Default = 20 Recommended range 1 £ and £ 30

FEA Interfaces
Patran
The Patran mesh interface has been enhanced to handle cases where the mesh elements have a physical property table entry defined, yet the actual physical property table entry does not exist. The FEA Interfaces are available from the File pull-down menu of the Control Panel and the Modeler.

Ansys
The ANSYS interface has been updated to accept lines up to 120 characters long. Previously it would accept lines of up to 80 characters. This change permits the reading of finite element meshes created in ANSYS R5.3 format with long line formats.

IDEAS
The IDEAS interface has been updated to accept IDEAS Master Series 5 meshes.

Weldlines and Air Traps
Improved usability and maintainability
The Weldlines and Air-traps module has been reorganized for better usability and future maintainability. Most users won't be notice any difference. If you run the cweld executable manually-that is, not from the Control Panel or using cmlaunch-you should note that the program argument is now required. Previously, cweld with no argument would assume Filling/EZ results were present. The arguments to cweld are:
• • • •

flowez (for processing Filling/EZ results) flow (for processing Filling and Filling & Post-filling results) gasflow (for processing Gas-assisted results) set (for processing Reactive results)

To run cweld manually, arrange all your input files in a working directory and include the cflcom.fnm file containing the shared name of the input files. Then run cflowez for Filling/EZ, cflow for Filling, cpack for Filling and Post-filling, and so on. After running the filling program, run cweld manually by typing the command and the appropriate argument (listed above). It is usually more convenient to use the Control Panel for setting up and launching the jobs; this takes care of the cflcom.fnm file and running cweld for you. If you use the Control Panel or cmlaunch to run the simulation modules, these changes won't affect you.

Material Database
Specific heat datasets
Some datasets that contained a large number of specific heat versus temperature pairs could cause performance problems with the Control Panel and Process Estimator . The number of these pairs of datasets has been reduced. A general review of the specific heat datasets was also made to ensure consistent data values.

Known Problems in this Release
Windows stacking out of order
The problem
On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence will sometimes stack windows in the incorrect order, placing the informational message under a file selection dialog. If you have not saved your design prior to opening the Design Diagnostics dialog, you will be prompted to first save your design when you try to leave the dialog. Because of the problem stated above, the Design Diagnostics dialog will remain on top of the Save Design selection dialog.

The solution
Dismiss the Design Diagnostics dialog with the Close command on the window menu button (in the upper-left corner of the window frame). Even though you dismiss the dialog, your Run Now, Run as Batch, or Cancel selection will be processed. You can then save your design. The workaround is to save your design before opening the Design Diagnostics dialog.

Release Notes 97.7
The 97.7 release of C-MOLD is a general release available to all customers with current Support & Update agreements. These notes describe what is new since the 97.1 general release in November of 1996. Monthly releases
In addition to twice yearly general releases, our monthly incremental releases provide for timely problem corrections and the implementation of new features. When applicable, the incremental release version of a fix or enhancement is noted in the monthly summaries. Copies of the monthly release notes issued since the last general release are contained in Appendix A of this document. For information on obtaining the latest monthly incremental release, contact your local C-MOLD office (see Appendix B for a listing). The C-MOLD web page is also a good place to look for the latest information about our products.

Keyfiles
Provided your Support & Update agreement is current and you are updating from a 96.7 or higher version, your existing keyfile will enable this release. If you are updating directly to the 97.7 release from a v4 or 96 release prior to 96.7, you will need a new keyfile. If using your existing keyfile with the 97.7 release results in an inconsistent encryption error, contact your local C-MOLD office to obtain your new keyfile. You can check your C-MOLD license key for the recorded Support & Update expiration date. Find the line with the key for C-MOLD that looks like this:
2eac 4f4a 8ah6 8d74 23d6 28gf d373 6k93 cmold NO EXPIRY 12/01/96 15users

The date in mm/dd/yy format is your Support & Update expiration date. To run 97.7, this date must be after 03/31/97. If you have a question about your Support & Update agreement, please contact your local C-MOLD office.

What's changed in this release?
These release notes summarize all that's new and different in the system since the last general release.

Running C-MOLD
It is now possible to operate in the root directory. While uncommon for UNIX users, some Windows users might want to start in the root directory.

Installation procedure
This release uses the same interactive procedure as the 97.1 release to guide you through the installation process. Most users will be able to install C-MOLD 97 without system administrator assistance in less than ten minutes. See the inside cover of your CD case for complete installation instructions. You can also install C-MOLD and work in folders whose names contain spaces. This is available on both the UNIX and Windows version, although spaces in directory and filenames are more common in Windows than in UNIX.

C-MOLD License Manager
The License Manager -status command was enhanced to provide you with information about floating licenses in use. For each floating license in the keyfile, you can find out the licensed number of seats or nodes, how many are currently in use, and how many remain available. For licenses in use, the computer system ID and the process ID (PID) using the license are also displayed. Note that multiple copies of the same interactive module launched from the Control Panel use a single license and the status report will show only the first process ID that obtained the license for that display. To track down a particular user running C-MOLD from a UNIX machine, you need to determine the machine that matches the system ID and use the UNIX ps -eaf | grep PID command. On Windows, use the Task Manager to find the user matching the process ID.

Hardware platforms
New platform
In response to customer requests, C-MOLD has been ported to the Digital Alpha generation series of workstations running the Alpha NT version of Windows. If you want to run CMOLD on an Alpha NT Workstation, please contact your C-MOLD office.

Hardware support summary
C-MOLD 97.7 is supported on the following hardware platforms and operating systems. We periodically update this list to reflect currently available and popular operating system levels. Please refer to C-MOLD System Administrator Guide for detailed hardware, software, graphics, and window system requirements.
• • • • • • •

DEC Alpha OSF1 (OSF/1 2.0) Digital Alpha AXP (Windows NT) HP700 (HPUX 9.01) IBM RS/6000 (AIX 3.2.5 and AIX 4.1) PC Pentium (Windows NT 3.51) PC Pentium (Windows 95)1 SGI (IRIX 5.2)

•

SPARC (Solaris 2.4, SUN OS 5.4)

C-MOLD Control Panel
Injection/compression dialog
The Design Diagnostics dialog for launching an injection/compression molding process from the Control Panel has been changed to look more like the dialog for launching an injection molding process.

Mold process icon
This release corrects a sizing problem with the mold process icon corresponding to the process being simulated. In some of the incremental releases since 97.1, the bitmap image of the selected process could be partially obscured by the mesh pull-down menu.

Windows users
Run directories
C-MOLD uses run directories for storing intermediate results while the simulations are executing. On Windows NT and Windows 95 systems, these directories would sometimes not be removed after the Run Now or Run as Batch job had completed. These empty directories were harmless, but could be confusing. With the 97.6 release, these temporary run directories are now properly removed once the analysis completes.

Small version of C-MOLD
It is possible to use a smaller-windowed version of C-MOLD by setting the CMOLD_SMALL environment variable before launching the application. This is useful when using a system with limited screen resolution or to maximize screen real estate when you want to work with several windows open at once.

UNIX users
In UNIX systems, in csh for example, you should enter the following:
setenv CMOLD_SMALL yes

Windows users
In Windows systems, you should enter:
set CMOLD_SMALL=yes

C-MOLD Cooling Simulation

Coolant manifolds
Attempting to run a Coolant Flow simulation when there were no coolant manifolds (circuits) defined in your model used to cause a program error. The workaround was either not to run a cooling analysis when you had no coolant manifolds defined, or to add coolant manifolds to your model. The problem was fixed in the 97.6 incremental release, so that the program error no longer occurs. However, you do still need to define at least one coolant manifold in order to run a Cooling analysis.

Mold wall temperature convergence criterion
Change in the default value
With the January 1997 incremental release of C-MOLD 97.4, the default value for the mold wall temperature convergence criterion (T-CODE 313) has changed from 0.05 to 0.01 percent. This value is set in the parameter (.par) file. The change increases the accuracy of results at the expense of a longer computation time. The reason for this change is that changing the region normal direction sometimes produced different cooling results. This could be seen by comparing the results of two cooling analyses run on the same geometry, with the exception of a change in the region normal definition. The results should have been identical, but in some cases, they were not because the solution had not converged. To achieve the correct result, we needed to reduce the mold wall temperature convergence criterion.

Accuracy of the solution
To judge the accuracy of the Cooling simulation results, you should refer to the residual value. The residual is printed in the log file or on the screen at the end of the iterative run. For an exact solution, the residual would be zero. A value of about 0.01 or smaller indicates the results are accurate. A residual greater than about 0.01, indicates that the solution has not yet reached the desired level of accuracy. In this case, you should reduce the mold wall temperature convergence criterion by a factor of two, and re-run the analysis.

Reducing computation time
To save computation time, you should also turn on the Save restart file (T-CODE 520) switch in the parameter file by setting its value to 1. This will retain the geometry information for your model in case you need to run the analysis again, and save about onethird the computation time. You should keep in mind that the restart file can occupy a lot of disk space. Note that the residual is not what is being compared against the mold wall temperature convergence criterion. The residual is computationally expensive to calculate, and recalculating it would dramatically increase the computation time of the cooling analysis. For this reason, the residual is computed only once, at the end of the iterative solution. The iterative solution convergence is checked by comparing each iteration's result to the previous iteration's values, and comparing this percentage change to the mold wall

temperature convergence criterion. When the percentage change from one iteration to the next is less than the mold wall temperature convergence criterion, the iterations stop, and then the residual is computed.

C-MOLD Coolant Flow
The Coolant Flow simulation has been re-written to make the code easier to maintain and to improve the robustness and accuracy of the product. The customer also benefits in the following ways.

Benefits to the customer
• • • • •

•

Better computational efficiency with no change in the usage of the analysis and output data. More robust behavior in handling disk-like cooling channel elements with large diameter/length (D/L) ratios (e.g., D/L > 40). Elimination of program defects that occasionally caused questionable pressure distribution predictions in bubblers. Capability of handling bubblers and baffles with variable (step-wise or tapered) cross sections. Consistent total-pressure-drop vs. total-flow-rate solutions. Namely, if one uses the predicted (output) total flow rate as the input, the new analysis will generate the original total pressure drop. Correction of the Reynold's number calculation in certain situations.

Examples
The new Coolant Flow analysis became available beginning with the 97.4 incremental release. We present three examples below, and compare the predictions from the previous version (C-MOLD 97.3 and earlier) with those of the new version. Example 1: Cooling channels with large D/L ratios The first example deals with a cooling circuit that contains one disk-like cooling channel element with a large D/L ratio (as shown at the junction between the largest and the smallest channel elements in the top section in Figure 1). This disk-like cooling channel element will cause abnormal termination of the Coolant Flow analysis in C-MOLD 97.3 and earlier versions. The workaround for this problem is to re-mesh the cooling channels so that the D/L ratio is at least larger than 1. However, the new implementation in C-MOLD 97.4 handles elements with large D/L ratios without having to re-mesh, and successfully produces solutions, as shown in the lower section in Figure 1.

Figure 1 Example 2: Coolant pressure distribution in bubblers The second example involves a combination of parallel bubblers (four in a group) connected in series. The coolant pressure distribution along the bubblers predicted by CMOLD 97.3 and earlier versions is shown in Figure 2.

Figure 2 Normally, one would expect to see a monotonic decrease in pressure from the base of the bubbler to its tip, as the pressure drop is the driving force for coolant flow. As Figure 2 illustrates, however, the pressure at the tips of the bubblers predicted by older versions of C-MOLD is actually higher than the predicted pressure at upstream locations. The problem has been fixed in C-MOLD 97.4, and the more reasonable solution is shown in Figure 3.

Figure 3 Example 3: Pressure distribution in elements with variable diameters This example illustrates the functionality added in C-MOLD 97.4, which enables the Coolant Flow analysis to handle bubblers and baffles that have variable (step-wise or tapered) diameters. Shown in Figure 4 is the predicted pressure distribution within a group of five straight bubblers, connected in parallel. There is only a small pressure drop along the two cooling channels that connect the five bubblers. Most of the pressure drop occurs along each of the bubblers, which have higher flow resistance due to the divided, inner and outer flow paths. For this case, the required overall pressure drop to deliver a user-specified flow rate is 400 Pa (0.0004 MPa).

Figure 4 If one employs bubblers with step-wise cross sections, as shown in Figure 5, the required pressure drop increases significantly (from 400 Pa to 5,400 Pa) as a result of more restrictive flow areas. This new function in C-MOLD 97.4 makes it possible to simulate cases in which bubblers or baffles of variable diameters are used due to special design requirements.

Figure 5

C-MOLD Filling & Post-Filling Simulation
Juncture loss calculation
The Filling and Post-Filling simulations have improved handling of the juncture loss calculations. The change allows for the juncture loss calculation to take place whenever the runner diameter changes. Previously, there needed to be a change of diameter greater than or equal to 2 for the juncture loss calculation to take place. When you are especially concerned about pressure losses in the melt delivery system, consideration of juncture losses should be included in your simulation. To model juncture losses, C-MOLD uses the two Bagley correction constants, C1 and C2. See Appendix C of C-MOLD Rapid Designer User's Guide for more information.

Enhancement of juncture loss model

The C1 and C2 juncture loss model was derived from capillary viscosity data. This model can accurately describe the extra pressure loss at the juncture of a tube and a reservoir. In a typical runner and gate design, however, the abrupt size change is not as drastic as the change between a tube and a reservoir. Therefore, the juncture loss (or extra pressure drop) is not as significant as the data derived from capillary viscosity data. In the limiting case, this extra pressure drop equals zero at the juncture of two tubes with the same diameter. Prior to the C-MOLD 96.12 release, juncture loss was applied to pressure calculations only when two consecutive runner or gate elements had a diameter ratio greater than 2. This meant that the extra pressure loss was applied only to elements with an abrupt change in size between them. With the 97.1 release, we enhanced the juncture loss calculations by using a continuous model that can be applied to all runner and gate elements in the mesh. Now:
• •

If the diameter ratio equals 1, then extra pressure drop equals zero (no juncture loss occurs when the diameters are the same). If the diameter ratio equals infinity, then extra pressure drop equals the calculated value from the C1 and C2 model. It is a continuous model, so it can be applied to all runner and gate elements in the mesh.

Incorrect C1 value in juncture loss conversion
It came to our attention recently that there was a problem with the reported juncture-loss data for materials tested in the C-MOLD Polymer Laboratory. The mistake occurred when converting from CGS to SI units. C1 is undervalued, and the net effect depends on the C2 value: If C2 = 1 then C1 is 1/10 of what it should be. If C2 = 2 then C1 is 1/100 of what it should be.

Corrections to 97.5 release
Corrections have been made to the C-MOLD resin database and were included in the 97.5 release. We ran a series of simulations to gauge the effect of using the correct C1 value and the enhanced juncture-loss modeling. The data from the C-MOLD simulation was compared to experimental data generated at the Cornell Injection Molding program, and led to a very close match with the experimental data. Based on this information, we can report that you should see improved results when using C-MOLD 97.5 and later releases.

Impact on releases prior to 97.1
We expect that there would be little impact on the simulations you may have run using CMOLD releases prior to 97.1. Remember that in those versions, the juncture-loss calculations were applied only when the ratio of the diameters of two consecutive runner elements was greater than 2; in other words, when there was an abrupt change in gate or runner sizes. Tests also showed that:

• •

Using the incorrect C1 value and the old juncture-loss calculation methods made no difference to the predicted gate pressure. Using the correct value of C1 with the old juncture-loss calculation method led to over-prediction of juncture loss.

C-MOLD Modeler
Point attributes
We fixed a problem involving the deletion of point attributes when running on 64-bit UNIX machines, such as the MIPS IV SGI and DEC Alpha. Although you could previously set and query point attributes like polymer entrances, you could not delete them.

Mesh
Mesh nodes
The Mesh pull-down menu contains commands for editing mesh nodes and elements. In previous releases, moving mesh nodes could cause the Modeler to crash under certain circumstances. This problem was resolved in the 97.3 incremental release.

Mesh size
An infinite loop used to occur if meshing was performed on surface or region boundaries when no mesh size information was assigned. New mesh size checks were added to avoid this.

Duplicate entities
Due to internal constraints in the Modeler's geometry database, duplicate entities, such as points, are not allowed. To determine when two points are at the "same" location, a tolerance needs to be used. This tolerance was decreased in the 96.12 release to solve a problem involved in importing several IGES models. Although internal testing on hundreds of models uncovered no problems with this tolerance change, problems have surfaced in the field in which models either can no longer be read into the Modeler or become corrupted (unreadable) after being read into the Modeler and saved. The problem was traced to the tightening of the internal tolerance, which caused more points to be identified as duplicates and merged. When these duplicate points were used by other entities yet to be read from the model, merging them often caused the model to become corrupted. The 97.5 incremental release of the Modeler addresses this serious problem with a collection of fixes. Our tests indicate that the 97.5 and later releases of the Modeler can successfully read and save uncorrupted models created by both 96.7 and 97.1 versions of the Modeler. Likewise, tolerance problems with reading IGES and GEO format models were corrected. Now when the Modeler attempts to read a corrupted model, the information up to the point of damage is successfully read, and you are prompted to save the model immediately. You are then able to reload that model and retain all the

uncorrupted information. Although the model corruption problem is most prevalent when importing large IGES models containing many closely spaced points, it can also happen on models built entirely within the Modeler.

Problems with IGES models
Why do the IGES models sometimes cause problems in the Modeler? One reason for the duplicated points and entities is that many IGES models originate from solid models. In a solid model, where two faces join, there is a single, shared joining boundary curve. In the IGES representation, each face can get its own set of boundary curves. This results in two boundary curves-at the same or nearly the same physical location-at the boundary between the two faces. The Modeler's internal geometry database does not allow for duplicated points and entities. Since the current IGES import function performs only duplicate point detection and clean up, the task of detecting other duplicated entities is left to the user. To manually detect and clean up duplicate points: 1 Select the Edit Geometry; Merge Points command from the Modeler, and choose a method of merging points. The system will display messages informing you which points it can't merge. 2 Query Geometry on these points to find which entities reference the points and then clean up these entities. In this way, your converted IGES model will be a "legal" C-MOLD model

C-MOLD Rapid Designer
In response to user requests, when adding your own data for the Moldflow 2nd order viscosity model, you can now specify any of the seven constants as either a positive or negative value. Previously, not all constants were allowed to be negative.

C-MOLD Shrinkage and Warpage Analysis
Windows users
The .slf service loading file output from the Modeler was being incorrectly read by the Windows version of the Shrinkage and Warpage module. Non-zero loads or moments could possibly be interpreted incorrectly, leading to incorrect results. The problem was corrected in the 97.4 incremental release.

Fixities
When performing the Shrinkage and Warpage Analysis the model needs to be constrained for rigid-body translations and rotations. Six degrees of fixity (X, Y, Z translations and rotations about X, Y, and Z axes) are needed.

Version 97.1
In the 97.1 version, in each substructure (e.g., cavity in a multicavity mold), the free rigidbody motions are prevented by fixing six degrees of freedom at three nodes. These three nodes were determined by C-MOLD Residual Stress and stored in the neutral (.neu) file. At the first node, the translations are set to zero. The second node lies on the line N1-N2 of the initial shape. The third node lays in the plane defined by N1-N2-N3 of the initial shape. CMOLD Residual Stress chooses these three nodes for each substructure of the part; that is, if the part consists of several mechanically independent substructures (e.g., a multi-cavity mold where each cavity is treated separately), each substructure has its six fixities assigned. When reviewing displacement results in C-MOLD Visualizer, it is important to consider that displacement is related to the fixities and corresponding best fit transformation. When comparing to measurements of an actual part, an anchor plane should be defined to match the constraints on the measuring device. Chapter 4 and Appendix B of the C-MOLD Shrinkage & Warpage User's Guide describes this in more detail.

Version 97.7
In the 97.7 version, the six degrees of fixity are determined by the C-MOLD Shrinkage & Warpage module. For each substructure, a node near the geometric center of the substructure is found and the translations and rotations set to zero there. This is possible because of a reworking of the element formulation used in C-MOLD Shrinkage & Warpage and an increase in the numerical precision of the neutral (.neu) file. Previously, we've used Allman's membrane element, which, due to its formulation, required the fixities to be defined at three nodes. With new enhancements to Allman's element based on research at the Cornell Injection Molding Program, the requirement of three nodes is removed and the fixities can be placed at a single node. This makes the module easier to develop and verify as well as more efficient computationally. This new element formulation is somewhat stiffer than before, which will reduce predicted warpage. The change in the neutral (.neu) file involves using G16.8 format instead of G12.4 format. This provides up to four additional digits of precision to prevent unbalanced loads from accumulated truncation errors. If you have developed your own interface from the neutral (.neu) file to a structural analysis program, you should review it to see if any changes are needed.

Distance results
You can expect that distance results will be close to previous values, but usually with slightly smaller changes to the original distance due to the stiffer element formulation. Distance between nodes is the best way to compare results because it does not depend on the coordinate system (e.g., anchor plane). With the differences in the anchor plane

definition between the two versions, trying to compare displacement contour or shaded plots is not feasible because redefining the anchor plane in C-MOLD Visualizer does not affect the contour and data-shaded plots.

Comparing results between versions
To do the comparison on your model, follow these steps. 1 Use C-MOLD Visualizer to open the Shrinkage & Warpage outputs on your 97.1 results. 2 Establish the anchor plane to match how your physical data was measured or to a convenient reference. Note the node labels of your reference plane. C-MOLD Visualizer's Select Anchor Plane plot will be helpful here. 3 Query the distance between important datum nodes in your model and record the information. 4 Run C-MOLD Shrinkage & Warpage on the same model and use the Visualizer to open the new outputs. 5 Establish the anchor plane using the same nodes used before and again query the distance between the nodes recorded earlier. Of course the original distances should be identical and the computed distances should correspond with your recorded values. Now notice how the displacement plot shown as a contour or data-shaded plot looks different than before. This is because, during the calculation, different fixities were used (the anchor plane defined in the neutral file for 97.1 and the "geometric center node" for 97.7). Since redefining the anchor plane in C-MOLD Visualizer does not affect the contour and data-shaded plots, the results look different between the two versions. However, as seen from the distance between nodes results, which is coordinate-system independent, the versions give close to the same answers. During development of the revised Allman's element, analytical derivation and numerical tests showed the new formulation eliminates disadvantages in the previous formulation.

C-MOLD Visualizer
The enhancements in the C-MOLD Visualizer have centered on the print function in this general release.

Printing
PCX
The PCX hard copy driver now supports direct color and/or pseudocolor visuals.

Print dialog
The print dialog has been modified to merge the White-to-black and Black background toggles into a single Reverse black/white toggle. The black/white reverse option is available for both TIFF and RGB outputs.

FEA Interfaces
The number of formats with which C-MOLD can interface has increased, and the translation requirements have changed slightly in this release. The FEA Interfaces are available from the File pull-down menu on the Control Panel and the Modeler.

Moldflow interface
Moldflow release 9 files are now supported. You can run the Moldflow Release 9 to CMOLD Mesh (mf90fem) interface by typing its name at a command prompt or from the File; FEA Interfaces menu in the Control Panel and the Modeler.

Ansys, Patran, and IDEAS interfaces
Polymer entrance nodes
The default number of polymer entrance nodes has changed from one to zero. This requested change makes it easier to translate a file when the node numbers are unknown. If you don't know the entrance node numbers, you can accept the default value (zero) by pressing Enter when prompted for the number of polymer entrance nodes. This will bypass the prompts for the polymer entrance node values. Before running a C-MOLD analysis, you'll still need to specify the proper polymer entrances. This can be done in the FEA

Interface by giving the number of entrance nodes and their labels or by using the C-MOLD Modeler to assign the polymer entrances.

Ansys
C-MOLD now supports Ansys release 5.3.

PATRAN
A problem in translating part runner elements from PATRAN format files has been corrected.

User Interface
The user interface of C-MOLD's interactive modules-the Control Panel, Modeler, Visualizer, and Rapid Designer-was changed slightly in this release.

System palette
Windows users
In Windows versions of the C-MOLD interactive modules, you'll find a series of icons in the lower right side of the window called the system palette. These icons allow for easy access to such functions as starting an editor or reading your mail. On Windows 95 and NT versions, these icons are now attached to common Windows application programs.

On-line browsing capabilities
We've added a new icon to the system palette in the form of a bookshelf. When selected, the icon launches an HTML browser on our on-line documentation titles. The fully indexed C-MOLD documentation is now only a mouse click away whenever you need a quick reference. The user can also use this tool to access other Web-based resources, such as material suppliers' home pages or industry forums. A graphical icon also allows the user to send e-mail from within the C-MOLD environment. Sending e-mail from within C-MOLD allows for real-time, global sharing of C-MOLD simulation results with internal and external customers and project team members. Future applications of this capability include the ability to download material or molding machine data from the C-MOLD Web site or from a supplier site directly into the CMOLD database. Users have the ability to view C-MOLD's monthly incremental releases on the Web, and will eventually have the capability to select specific enhancements that can be immediately downloaded to produce custom software.

Known Problems in this Release

Windows stacking out of order
The problem
On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence will sometimes stack windows in the incorrect order, placing the informational message under a file selection dialog. If you have not saved your design prior to opening the Design Diagnostics dialog, you will be prompted to first save your design when you try to leave the dialog. Because of the problem stated above, the Design Diagnostics dialog will remain on top of the Save Design selection dialog.

The solution
Dismiss the Design Diagnostics dialog with the Close command on the window menu button (in the upper-left corner of the window frame). Even though you dismiss the dialog, your Run Now, Run as Batch, or Cancel selection will be processed. You can then save your design. The workaround is to save your design before opening the Design Diagnostics dialog.

Appendix A: Incremental Release Notes
Incremental releases provide a method for us to quickly provide problem resolution as well as early implementation of new features. Our last general release to all customers with current support & update agreements was made in November of 1996. The following incremental release notes make up this appendix:
C-MOLD 97.2 Release Notes C-MOLD 97.3 Release Notes C-MOLD 97.4 Release Notes C-MOLD 97.5 Release Notes C-MOLD 97.6 Release Notes

C-MOLD 97.2 Release Notes
These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD sales and technical support office.

Installation Procedure
This release uses a new interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD 97 without system administrator assistance in less than ten minutes. You might need superuser privileges in order to mount the CD or install C-MOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator. The information-packed Installation Guide has been renamed C-MOLD System Administrator Guide, and is intended for use by your system administrator for setting up special configurations and/or troubleshooting system problems.

UNIX machines
These instructions will work for the following hardware platforms: HP 9000, DEC AXP OSF/1, IBM RS6000, Sun SPARC Solaris 2.4 (OS5.4), and SGI (MIPS 1 and MIPS IV). SGI users should install the MIPS IV version only if they are using a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions. 1 Insert the CD-ROM into the computer.

2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. 4 Type cd cdrom_dir. 5 Type install, and follow the on-screen instructions.

Windows NT and 95 machines
Follow these instructions if you're running on Windows NT or Windows 95. 1 Locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. 2 Run setup.exe

Enhancements in this Release
Visualizer
PCX hard copy driver now supports direct color and/or pseudocolor visuals. C-MOLD Visualizer allows enabling of black/white reversal for both TIFF and RGB outputs.

Filling & Post-Filling
These analyses have improved handling of the juncture loss calculation. The change allows for juncture loss calculations to take place whenever the runner diameter changes. Previously, there needed to be a change of diameter greater or equal to 2 for the juncture loss calculation to take place.

Problems Corrected in this Release

C-MOLD Injection Compression Molding simulation can now be launched from the CMOLD Control Panel.

C-MOLD 97.3 Release Notes
These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD sales and technical support office.

Installation Procedure
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD 97 without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or to install C-MOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator. The information-packed Installation Guide has been renamed C-MOLD System Administrator Guide, and is intended for use by your system administrator for setting up special configurations and/or troubleshooting system problems. It is available in HTML format on the CD, from our web site www.cmold.com or in hard copy format. A printed copy was included with the November general release.

UNIX machines
These instructions will work for the following hardware platforms: HP 9000, DEC AXP OSF/1, IBM RS6000, Sun SPARC Solaris 2.4 (OS5.4), and SGI (MIPS 1 and MIPS IV). SGI users should install the MIPS IV version only if they are using a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir

SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. 4 Type cd cdrom_dir. 5 Type ./install, and follow the on-screen instructions. HP users will need to type ./INSTALL\;.

Windows NT and 95 machines
Follow these instructions if you're running on Windows NT or Windows 95. Intel CPU: 1 Locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. 2 Run setup.exe Alpha AXP CPU: 1 Locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. 2 Run setup.exe

Enhancements in this Release
FEA Interfaces
Ansys release 5.3 is now supported. Moldflow R9 files are now supported. The mf90fem program is not yet installed in the pull-down menus of the Control Panel and the Modeler. You can run the mf90fem interface by typing its name at a command prompt. A future release of C-MOLD will add this interface to the pull-down menus.

Visualizer
The print dialog has been modified to merge the "white to black" and "black background" toggles into a single "reverse black/white" toggle.

Rapid Designer
When adding your own data for the Moldflow 2nd order viscosity model, you can now specify any of the seven constants as either a positive or negative value. Previously, not all constants were allowed to be negative.

C-MOLD
It is now possible to operate in the root (/) directory. While uncommon for UNIX users, some Windows users may want to start in the root directory. It is now possible to install C-MOLD and to work in folders whose names contain spaces. This is available on both the UNIX and Windows versions of C-MOLD although spaces in directory and filenames are more common in Windows than in UNIX. Digital Alpha AXP workstations running Windows NT are now supported. In response to customer requests, C-MOLD has been ported to the Digital Alpha generation series of workstations running the Alpha NT version of Windows. If you want to run C-MOLD on an Alpha NT workstation, please contact your C-MOLD sales and technical support office.

Problems Corrected in this Release
Modeler
A problem involving moving mesh nodes which may cause the Modeler to crash has been corrected. In the mesh pull-down menu there are commands for editing mesh nodes and elements. In certain circumstances, moving mesh nodes could cause the Modeler to crash. This problem has been corrected in the 97.3 release.

Installation procedure
A problem copying your existing key file to the new installation location has been corrected.

C-MOLD 97.4 Release Notes
These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD sales and technical support office.

Installation Procedure
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD 97 without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or to install C-MOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator. The information-packed Installation Guide has been renamed C-MOLD System Administrator Guide, and is intended for use by your system administrator for setting up special configurations and/or troubleshooting system problems. It is available in HTML format on the CD or in hard copy format. A printed copy was included with the November general release.

UNIX machines
These instructions will work for the following hardware platforms: HP 9000, DEC AXP OSF/1, IBM RS6000, Sun SPARC Solaris 2.4 (OS5.4), and SGI (MIPS 1 and MIPS IV). SGI users should install the MIPS IV version only if they are using a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. 4 Type cd cdrom_dir. 5 Type ./install, and follow the on-screen instructions. HP users will need to type ./INSTALL\;.

Windows NT and 95 machines
Follow these instructions if you're running on Windows NT or Windows 95. Intel CPU: 1 Locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. 2 Run setup.exe Alpha AXP CPU: 1 Locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. 2 Run setup.exe

Enhancements in this Release
Coolant Flow
The Coolant Flow Analysis has been re-written with the following objectives and benefits. Objectives:
• • •

Rewriting the C-MOLD Coolant Flow Analysis code for easy maintenance and extension in the future. Making use of state-of-the-art software development tools and functions for shorter time-to-market development cycle and better computational efficiency. Making necessary modifications to improve the robustness and accuracy of the CMOLD Coolant Flow Analysis.

Benefits:
• • • • •

Better computational efficiency with no change in the usage of the analysis and output data. More robust behavior in handling "disk-like" cooling-channel elements with large diameter/length (D/L) ratio (e.g., D/L > 4.0). Elimination of program defects that occasionally caused questionable pressure distribution predictions in bubblers. Capability of handling bubblers and baffles that have variable (step-wise or tapered) cross sections. Consistent total-pressure-drop vs. total-flow-rate solutions. Namely, if one uses the predicted (output) total flow rate as the input, the new analysis will generate the original total pressure drop.

Cooling Analysis
The default value of the mold wall temperature convergence criterion has been changed from 0.05 to 0.01 percent. This change increases the accuracy of results at the expense of a longer computation time. In some cases, it was noted that only changing the definition of the region normal incorrectly changed the cooling analysis results. Reducing the mold wall temperature convergence criterion reduces this effect. The value of 0.01 percent is a balance between the increased computation time and the increased accuracy. To judge the accuracy of the cooling analysis result, you should consider the residual value displayed with the console messages at the end of the cooling analysis. A value of about 0.01 or smaller indicates the results are accurate. If the residual is greater than that, you may want to halve the mold wall temperature convergence criterion and re-run the cooling analysis. The mold wall temperature convergence criterion is set in the parameter (.par) file.

FEA Interfaces
In Ansys, Patran, and IDEAS interfaces, the default number of polymer entrance nodes has changed from one to zero. This requested change makes it easier to translate a file when the node numbers are unknown. If you don't know the entrance node numbers, when prompted

for the number of polymer entrance nodes, just press the Enter key to accept the default value of zero. This will bypass the prompts for the polymer entrance node values. Before running a C-MOLD analysis, you still need to specify the proper polymer entrances. This can be done in the FEA Interface by giving the number of entrance nodes and their labels or using the C-MOLD Modeler to assign the polymer entrances. Moldflow R9 is now available in the FEA Interfaces menu. The FEA Interfaces were enhanced in the 97.3 release to include support for Moldflow R9 files. In the 97.4 release, this support is extended to make the Moldflow R9 to C-MOLD Mesh interface available from the FEA Interfaces menu in the Control Panel and the Modeler. You can also run the mf90fem interface by typing its name at a command prompt.

License Manager
The License Manager -status command has been enhanced to provide information about floating licenses in use. For each floating license in the keyfile, information about the licensed number seats or nodes, how many are currently in use, and how many remain available is displayed. In addition, for licenses in use, the computer system ID and the process ID (PID) using the license is displayed. Note that multiple copies of the same interactive module launched from the Control Panel use a single license and the status report will show only the first process ID that obtained the license for that display. To track down a particular user running C-MOLD you need to determine the machine that matches the system ID and use the UNIX ps -eaf | grep PID command. On Windows machines, use the Task Manager to find the user matching the PID.

Problems Corrected in this Release
Modeler
A problem involving the deletion of point attributes running on 64-bit UNIX machines, such as the MIPS IV SGI and DEC Alpha, has been fixed. Previously, although you could set and query point attributes such as polymer entrances, you could not delete them. An infinite loop could occur if meshing was performed on surface or region boundaries when no mesh size information was assigned. New mesh size checks are made to avoid this. The IGES translator now automatically collapses points using a tolerance of 1.0e-10. This change resolves errors involving importing IGES files with points very close together. Previously "duplicated" points from the IGES file would be removed from the entity being processed without checking against other entities that may possibly have used the duplicate point. The new way collapses points in a safer manner. If you encounter an error while reading a CVG Modeler geometry file, you can save all the geometry that was read in before the error by immediately using the Save Geometry As function in the File pulldown menu. Then open the geometry data you just saved. Runners, cooling channels, and connectors (1D elements) may still be corrupted because they partially depend on topology information which may be in the corrupted portion of the original CVG file. At this time

there is no way to delete these corrupted 1D-type elements; however, you can use the Edit Geometry; Move Geometry command to move the corrupted 1D-type elements away from the good portions of your model. Why do the IGES models cause problems in the Modeler? One reason for the duplicated points and entities is that many IGES models are originally from solid models. In a solid model, where two faces join, there is a single shared joining boundary curve. In the IGES representation, each face can get its own set of boundary curves. At the boundary between the two faces, there can be two boundary curves occupying the same or nearly the same physical location. The Modeler's internal geometry database does not allow for duplicated points and entities. The current IGES import function does duplicated point detection and clean up. Duplicated entity detection and clean up is left to the user. From the messages generated by the Merge Points command, find which points can not be merged. Query Geometry on these points to find which entities reference the points and then clean up these entities. In this way, your IGES model will be safely converted.

License Manager
Some users reported that running the License Manager on an IBM workstation, IGES licenses were not being freed after the Modeler process was killed by the user. This apparently occurred often enough to be a problem, but not enough for easy debugging. Changes to the License Manager to implement the enhanced license status reporting are expected to remove any possibility of this occurring. In any case, the enhanced -status option will make it easier to see where licenses are being used.

Windows versions
C-MOLD Control Panel: When starting a new design, and using the "Use Existing" option to select the mesh, material, and process conditions files, and then going to Design Diagnostics directly without first saving your design it was possible to corrupt your mesh, material, or process conditions files. This only happened on Windows, and after you were prompted to save your design and answered the next prompt to overwrite the design file. The problem is corrected in 97.4. However, a problem remains for Exceed 5.1.1 users where the dialogs stack in the incorrect order. In order to save the design you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection-either Run Now, Run as Batch, or Cancel-will be processed. The workaround is to save your design before entering the Design Diagnostics dialog. C-MOLD Shrinkage and Warpage: The .slf service loading file output from the Modeler was being incorrectly read by the Windows version of the Shrinkage and Warpage module. Non-zero loads or moments could possibly be interpreted incorrectly leading to incorrect results. The problem is corrected in 97.4.

Installation on a Digital Alpha AXP workstation running Windows NT 4.0 failed in the 97.3 release. There is a problem in the InstallShield installation program. The workaround was to perform the installation under Windows NT 3.51 and copy the C-MOLD folder to the Windows NT 4.0 machine. With the 97.4 release, this problem has been resolved.

Known Problems in this Release
Coolant Flow
The Coolant Flow Analysis requires that all coolant manifold IDs defined in the process conditions (.prc) file exist in the modeled mesh (.fem) file. For example, if there are only two cooling manifolds defined in the mesh and there are three or more cooling manifolds defined in the process conditions, you will receive a message that the coolant entrance and exit are not defined. The workaround is to remove the extra cooling manifold specifications from the process conditions file.

Windows and Exceed 5.1.1
The Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the save design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the design diagnostics dialog, your selection-either Run Now, Run as Batch, or Cancel-will be processed. The workaround is to save your design before entering the Design Diagnostics dialog. The Design Diagnostics analysis program launching dialog does not properly set the "fast" cooling analysis option. Although you can set the option, it is not properly passed to the Cooling module, which then performs a full analysis. The work-around is to prepare all your input files, including cflcom.fnm containing the filename of your input files, and manual run ccool -fast. Please contact your technical support office for additional details.

C-MOLD 97.5 Release Notes
These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD sales and technical support office.

Installation procedure
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD 97 without system administrator assistance in less than ten minutes. You may need superuser privileges in order to mount the CD or to

install C-MOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator. The information-packed Installation Guide has been renamed C-MOLD System Administrator Guide, and is intended for use by your system administrator for setting up special configurations and/or troubleshooting system problems. It is available in HTML format on the CD or in hard copy format. A printed copy was included with the November general release.

UNIX machines
These instructions will work for the following hardware platforms: HP 9000, DEC AXP OSF/1, IBM RS6000 and PowerPC, Sun SPARC Solaris 2.4 (OS5.4), and SGI (MIPS 1 and MIPS IV). SGI users should install the MIPS IV version only if they are using a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. 4 Type cd cdrom_dir. 5 Type ./install, and follow the on-screen instructions. HP users will need to type ./INSTALL\;.

Windows NT and 95 machines
Follow these instructions if you're running on Windows NT or Windows 95. Intel CPU:

1 Locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. 2 Run setup.exe Alpha AXP CPU: 1 Locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. 2 Run setup.exe

Enhancements in this Release
Injection/ Compression
The launch dialog from the Control Panel for the injection/compression molding process has been changed to be more like the injection molding process launch dialog.

FEA Interfaces
The femchk interface to check C-MOLD-format finite-element mesh (.fem) files has been enhanced to allow for un-ordered nodes and/or elements. When nodes or elements are found to be out of order, they will be renumbered. Consecutively numbered nodes and elements are required for C-MOLD analyses.

Windows on interactive modules
In C-MOLD interactive modules, such as the Control Panel, Modeler, and Visualizer, at the lower right side of the window are a series of icons called the System Palette. These icons allow for easy access to such functions as starting an editor or reading your mail. On Windows 95 and NT versions, these icons are now attached to common Windows application programs.

Problems Corrected in this Release
Modeler
Due to internal constraints in the Modeler's geometry database, duplicated entities, such as points, are not allowed. To determine when two points are at the "same" location, a tolerance needs to be used. In the 96.12 release, this tolerance was decreased in order to solve a problem involved in importing several IGES models. Although internal testing on hundreds of models uncovered no problems with this tolerance change, in the field problems have surfaced where models either can no longer be read into the Modeler or become corrupted (unreadable) after being read into the Modeler and saved. The problem was traced to the tightening of the internal tolerance, which caused more points to be identified as duplicates and merged. When these duplicate points were used by other entities yet to be read from the model, merging them could cause the model to become corrupted.

The 97.5 incremental release of the Modeler addresses this serious problem with a collection of fixes. Our tests indicate that the 97.5 Modeler can successfully read and save uncorrupted models created by both 96.7 and 97.1 versions of the Modeler. Likewise, tolerance problems with reading IGES and GEO format models are corrected. With these fixes, when the Modeler attempts to read a corrupted model, the information up to the point of damage is successfully read, and you are prompted to save the model immediately. You are then able to reload that model and retain all the uncorrupted information. The model corruption problem is most prevalent when importing large IGES models containing many closely spaced points. However, it can happen on models built entirely within the Modeler. If you have run into corrupted models or often import IGES models, you are encouraged to install and run this incremental release.

Cooling Analysis
A problem in running the fast cooling option of the Cooling simulation has been corrected. In the previous release, the Design Diagnostics analysis launching dialog did not properly set the fast cooling analysis option. Although you could set the option, it was not properly passed to the Cooling module, which then would perform a full simulation. This is now corrected. In the 97.4 release, a new Coolant Flow simulation was shipped. Refer to the C-MOLD 97.4 Release Notes for details. In that release, if the number of cooling manifolds (circuits) defined in the process conditions (.prc) file did not match the number of manifolds in the mesh (.fem) file, an error would be generated. This has been revised so that the number of manifolds defined in the mesh is used to determine if there are enough definitions in the process conditions file. Any extra definitions in the process conditions file are ignored.

Control Panel
Running in the root directory is now possible. Although not common for UNIX users, running in the root directory may be common for PC users. Changes in the Control Panel now allow this.

Installation
On Windows 95 and NT platforms, the 97.4 release would report a missing dynamic link library, MSVCRT.DLL. Microsoft has changed the naming of their DLLs to no longer include the version number in the library name. The workaround was to copy the MSVCRT40.DLL to MSVCRT.DLL. With the 97.5 release, this problem has been resolved. The System Administrator Guide provides information about how to modify the Cmold application defaults file to use the OpenGL version of the Visualizer by default. The instructions there referred to lines not present in the file. In the 97.5 release, these lines are included in the application defaults file.

Known Problems in this Release

Windows and Exceed 5.5.1
On Windows and using Exceed 5.1.1, the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the informational message under a file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the Save Design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection-either Run Now, Run as Batch, or Cancel-will be processed. The workaround is to save your design before entering the Design Diagnostics dialog.

Coolant Flow
Attempting to run a Coolant Flow simulation when there are no cooling manifolds (circuits) defined in your model will cause a program error. The workaround is to add cooling manifolds to your model. This limitation will be removed in the next release.

Material Database Changes
Changes in the C-MOLD Material Database that have been implemented since the previous update are summarized in C-MOLD 97.5 Material Database Changes. Please refer to the Search the C-MOLD Material Database Web page to see what data is available for every material included.

C-MOLD 97.6 Release Notes
These notes describe what is new in this release. For information on obtaining the latest monthly incremental release, contact your local C-MOLD sales and technical support office.

Installation Procedure
This release uses an interactive procedure that guides you through the installation process. Most users will be able to install C-MOLD 97 in less than ten minutes, without system administrator assistance. You may need superuser privileges in order to mount the CD or to install C-MOLD to a restricted directory. If you run into problems installing the new release, consult your system administrator. The information-packed Installation Guide has been renamed C-MOLD System Administrator Guide, and is intended for use by your system administrator for setting up special configurations and/or troubleshooting system problems. It is available in HTML format on the CD or in hard copy format. A printed copy was included with the November 1996 general release.

UNIX machines
These instructions will work for the following hardware platforms: HP 9000 (tested on HPUX 9.01 and HP-UX 10.20), DEC AXP OSF/1 (tested on OSF/1.2 and OSF/1.4), IBM RS6000 and PowerPC (tested on AIX 3.2.5 and AIX 4.1), Sun SPARC (tested on Solaris 2.4 and 2.5), and SGI (MIPS 1 and MIPS IV) (tested on IRIX 5.2, 5.3, and 6.1). SGI users should install the MIPS IV version only if they are using a machine with an R8000 or higher CPU that is capable of executing MIPS IV instructions in 64-bit mode. Typically, newer versions of operating systems are upward compatible. 1 Insert the CD-ROM into the computer. 2 For all but SGI computers, type mkdir cdrom_dir, where cdrom_dir is the directory to which you'd like to mount the CD-ROM drive. 3 HP: type /etc/mount -rt cdfs /dev/dsk/#s0 cdrom_dir, where # is a digit reliant on your hardware configuration. DEC: type mount -t cdfs -o noversion device cdrom_dir, where device is the device name for your particular hardware configuration. IBM: type mount -v cdrfs -r /dev/cd0 cdrom_dir Sun: type mount -F hsfs -r /dev/sr0 cdrom_dir SGI: The mount is done automatically by the media daemon to /CDROM or /cdrom. Substitute the appropriate name (/CDROM or /cdrom) for cdrom_dir in the subsequent instructions. 4 Type cd cdrom_dir. 5 For all but HP computers, type ./install, and follow the on-screen instructions. HP: type ./INSTALL\;.

Windows NT® and Windows® 95 machines
Follow these instructions if you're using the Windows NT or Windows 95 operating system. Intel CPU (Windows NT or Windows 95): 1 Locate cd_rom_drive_letter:\cmoldxxx\winintel\ on the distribution CD. 2 Run setup.exe Alpha AXP CPU (Windows NT):

1 Locate cd_rom_drive_letter:\cmoldxxx\winalpha\ on the distribution CD. 2 Run setup.exe

Problems Corrected in this Release
Control Panel
It is possible to use smaller windows by setting the CMOLD_SMALL environment variable before starting C-MOLD. This is useful when using a system with limited screen resolution or when you want to have many windows going at once. In UNIX systems, in csh for example, you would enter the following:
setenv CMOLD_SMALL yes

In Windows systems, you would enter:
set CMOLD_SMALL=yes

This release corrects a sizing problem with the bitmap images corresponding to the process being simulated. In the previous release, the bitmap image of the selected process could be partially obscured by the mesh pull-down menu. On Windows NT and Windows 95 systems, the run directories used to store intermediate results while the simulations are executing sometimes would not be removed after the Run Now or Batch job had completed. These empty directories were harmless, but they could be confusing and should have been removed. These temporary run directories are now properly removed after the simulation is completed.

Cooling Analysis
Attempting to run a Coolant Flow simulation when there were no cooling manifolds (circuits) defined in your model would cause a program error in the previous release. The workaround was either not to run a cooling analysis when you had no cooling manifolds defined, or to add cooling manifolds to your model. The program error no longer occurs. However you do need to have at least one cooling manifold defined in order to run a Cooling simulation.

FEA Interfaces
A problem in translating part runner elements from PATRAN format files has been corrected. The FEA Interfaces are available from the File pull-down menu of the Control Panel and the Modeler.

Known Problems in this Release
Windows and Exceed 5.5.1
In Windows systems and using Exceed 5.1.1, the Control Panel analysis launching sequence can sometimes stack windows in the incorrect order, putting the

informational message under a file selection dialog. If you have not saved your design prior to entering the Design Diagnostics dialog, when you try to leave the dialog, you will be prompted to first save your design. However, the Design Diagnostics dialog will remain on top of the Save Design selection dialog. In order to save the design, you need to dismiss the Design Diagnostics dialog. Even though you dismiss the Design Diagnostics dialog, your selection-either Run Now, Run as Batch, or Cancel-will be processed. The workaround is to save your design before entering the Design Diagnostics dialog.