HEAT AND MASS TRANSFER VIVA QUESTIONS
1. Define Fourier Law of Conduction. 2. Explain how the heat gets transferred in case of conduction, convection and radiation. 3. Explain the differences between heat transfer co-efficient and overall heat transfer coefficient. 4. Define Steady state, unsteady state and Transient state of heat transfer. 5. Define Newton’s Law of Cooling. 6. What are Fin’s and how are they classified? 7. Give an example for fins in engineering application. 8. Define Convective heat transfer co-efficient 9. List the assumptions made for composite walls. 10. Define Thermal Conductivity of material. State which material has highest and lowest thermal conductivity? 11. Explain the Boundary Layer Concept in heat transfer mechanism 12. Define and classify heat exchangers 13. Why Logarithmic Temperature difference are considered in calculation of heat exchanger. 14. Differentiate between AMTD and LMTD? 15. Explain NTU in heat exchangers. 16. In heat exchangers, is heat transfer more in Parallel flow or Counter flow heat exchanger, Justify? 17. Differentiate between Forced and Natural Convection. 18. Is the heat transfer rate more in Forced convection or Natural Convection, Justify? 19. Explain the significance of Grashoff Number, Prandt’s number and Reynold’s nu mber in convection heat transfer. 20. Define Effectiveness and Efficiency of fin. 21. Define Effectiveness of heat exchanger. 22. Define COP. 23. Define 1 ton of refrigeration. 24. Name the refrigerants used in VCR and Air Conditioning. 25. List few refrigerants and list the properties of refrigerants. 26. Differentiate between Capillary and Throttling Mechanism is VCR. 27. Draw T-S diagram for Vapour Compression Refrigeration. 28. Define Dry Bulb Temperature, Wet Bulb Temperature, Humidity and Specific Humidity. 29. Define Sensible cooling, Sensible heating and adiabatic heating. 30. Define Specific heat and Latent heat of Ice. 31. Define Steffan’s Boltzmann law of radiation
32. Define Kirchoff’s law and Wein’s displacement lwa of radiation. 33. Differentiate between Black Body and Color Body. 34. Define Emissivity and Emissive Power. 35. Differentiate between Film-wise and Drop-wise Condensation. 36. Define Fick’s law of diffusion. 37. Define Heat and what is the unit of heat? 38. Differentiate between VCR, VAR and Air refrigeration.