Home » Mechanical VIVA Questions » 60 TOP MOST THERMAL Engineering VIVA Questions and Answers 60 TOP MOST THERMAL Engineering VIVA Questions and Answers Posted on June 11, 2015January 2, 2016 by engineer91 Comments THERMAL Engineering VIVA Questions and Answers :- 1. Define heat transfer? 2. What are the modes of heat transfer? 3. What is conduction? 4. State Fourier’s law of conduction. 5. Define Thermal conductivity. 6. Write down the equation for conduction of heat through a slab or plane wall. 7. What are the factors affecting the thermal conductivity? 8. What is meant by free or natural convection? 9. Define Grashof number [Gr]. 10. Define Stanton number [St]. 11. What is meant by Newtonion and non-newtonion fluids? 12. What is meant by laminar flow ? 13. Define Convection. 14. Define Reynolds number [Re]. 15. Define Prandtl number [Pr]. 16. Define Nusselt Number [Nu]. 17. State Newton’s law of convection. 18. What is forced convection? 19. What are the dimensionless parameters used in forced convection? 20. Mention Stefan boltzman contant. 21. Define Stefan boltzman contant. 22. Define Emissive power [Eb]. 23. Define monochromatic emissive power. [Ebλ] 24. What is meant by absorptivity? 25. Define Radiation. 26. Define Emissivity. 27. Define Emissive power [Eb]. 28. Define monochromatic emissive power. [Ebλ] 29. What is meant by absorptivity? 30. What is meant by reflectivity? THERMAL Engineering VIVA Questions and Answers :- 31. What is meant by transmissivity? 32. What is black body? 33. What is meant by gray body? 34. What is heat exchanger? 35. What is meant by Direct heat exchanger [or] open heat exchanger? 36. What is meant by Indirect contact heat exchanger? 37. What is meant by parallel flow heat exchanger? 38. What is meant by counter flow heat exchanger? 39. What is meant by cross flow heat exchanger? 40. What is meant by Shell and tube heat exchanger? 41. What is meant by LMTD? 42. What is meant by Effectiveness? 43. Power requirement of a refrigerator is___________. 44. In SI units, one ton of refrigeration is equal to _________. 45. Define tons of refrigeration and COP. 46. The capacity of a domestic refrigerator is in the range of ___________. 47. Name four important properties of a good refrigerant. 48. What is the difference between air conditioning and refrigeration? 49. Name any four commonly used refrigerants. 50. What are the advantages and disadvantages of air refrigeration system? 51. What is net refrigerating effect of the refrigerant? 52. Define refrigerant.