A. Re and Pr
B. Re and Gr
C. Pr and Gr
D. Re and Sc
Related Mcqs:
- Nusselt number (for forced convection heat transfer) is a function of the _____________ number?
A. Prandtl
B. Reynolds
C. Both A. & B.
D. Neither A. nor B. - Nusselt number is a function of Prandtl number and ______________ number of fluid in natural convection heat transfer?
A. Grashoff
B. Biot
C. Stanton
D. Reynolds - Heat transfer co-efficient equation for forced convection, Nu = 0.023 Re 0.8. Pr n, is not valid, if the value of __________________?
A. n = 0.4 is used for heating
B. n = 0.3 is used for cooling
C. Reynolds number for the flow involved is > 10000
D. Reynolds number for the flow involved is < 2100 - In forced convection, the heat transfer depends on _______________?
A. Re, Pr
B. Re, Gr
C. Mainly Gr
D. Re only - Which of the following is unimportant in forced convection ?
A. Reynolds number
B. Prandtl number
C. Grashoff number
D. None of these - Which of the following forced convection heat transfer equation accounts for the liquid viscosity effect for viscous liquids ?
A. Dittus-Boelter equation
B. Sieder-Tate equation
C. Nusselt equation
D. None of these - Forced circulation evaporators are useful for the concentration of viscous, salting and scale forming liquors. Which of the following is a forced circulation evaporator ?
A. Long vertical evaporator
B. Horizontal tube evaporator
C. Agitated film evaporator
D. Calandria vertical tube evaporator - Nusselt number is the ratio of the ____________________?
A. Temperature gradient of the wall to that across the entire pipe
B. Temperature difference to the temperature gradient at the wall
C. Heat flux at the wall to that across the entire pipe
D. None of these - The Sieder-Tate correlation for heat transfer in turbulent flow in pipe gives Nu α Re0.8, where, Nu is the Nusselt number and Re is the Reynolds number for the flow. Assuming that this relation is valid, the heat transfer co-efficient varies with the pipe diameter D. as _________________?
A. D-1.8
B. D-0.2
C. D0.2
D. D1.8 - What is Nusselt number ?
A. CP. μ/k
B. hD/k
C. h. CP/μ
D. CP. μ/h
