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
Related Mcqs:
- In forced convection, the Nusselt number is a function of ____________________?
A. Re and Pr
B. Re and Gr
C. Pr and Gr
D. Re and Sc - Nusselt number is the ratio of the temperature gradient at the wall to_________________?
A. Temperature difference
B. Heat flux
C. 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 - 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 - The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe, where the wall heat flux is constant, is__________________?
A. 2.36
B. 4.36
C. 120.36
D. Dependent on NRe only - Value of Nusselt number [Nu = (hD/k)] for the heat transfer by conduction from a droplet or a spherical particle to a surrounding stagnant film is__________________?
A. 0.5
B. 2
C. 10
D. 100 - 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. - The Nusselt number for fully developed (both thermally and hydrodynamically) laminar flow through a circular pipe whose surface temperature remains constant is______________?
A. 1.66
B. 88.66
C. 3.66
D. Dependent on NRe only - What is Nusselt number ?
A. CP. μ/k
B. hD/k
C. h. CP/μ
D. CP. μ/h - Rate of heat transfer by vaporisation from pools of water is affected by the ____________________?
A. Nature of heating surface and distribution of bubbles
B. Surface tension of water
C. Viscosity of water
D. All A., B. and C.
