Heat Transfer MCQs

61. 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

by
(D)-1.8
(D)-0.2
(D)0.2
(D)1.8
✅ The correct answer is option B.

65. In an interphase heat transfer process, the equilibrium state corresponds to equality of temperature in the two phases, while the condition for equilibrium in an interphase mass transfer process is equality of

by
Concentrations
Chemical potentials
Activity co-efficients
Mass transfer co-efficients
✅ The correct answer is option A.