A. Reynolds number
B. Prandtl number
C. Grashoff number
D. None of these
Related Mcqs:
- 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 - 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 - 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 - 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. - 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 - Fluid motion in the natural convection heat transfer between a solid surface and a fluid in contact with it, results from the_________________?
A. Existence of thermal boundary layer
B. Temperature gradient produced due to density difference
C. Buoyancy of the bubbles produced at active nucleation site
D. None of these - Critical value of the _____________ number governs the transition from laminar to turbulent flow in free convection heat transfer?
A. Grashoff
B. Reynolds
C. Both ‘a’ & ‘b’
D. Prandtl & Grashoff - In the free convection regime of pool boiling, the heat flux is proportional to__________________?
A. Δt1/2
B. Δt2
C. Δt5/4
D. Δt - The rate of heat transfer from a vertical plate by natural convection depends upon the temperature differences (ΔT) between wall and outside bulk. The proportionality is given as______________?
A. (ΔT)1/4
B. (ΔT)1/2
C. (ΔT)5/4
D. (ΔT)3/4
