Top 1000+ Solved Heat Transfer (HT) MCQ Questions Answer
Q. It is not recommended to use a 1-2 shell and tube heat exchanger for a particular heat duty, whenever the LMTD correction factor is
a. > 0.75
b. < 0.75
c. < 0.50
d. < 0.25
Q. Multiple effect evaporation accounts for
a. Steam economy
b. Lower operating costs
c. Investment economy
d. None of these
Q. Finned tube heat exchangers
a. Give larger area per tube
b. Use metal fins of low thermal conductivity
c. Facilitate very large temperature drop through tube wall
d. Are used for smaller heat load
Q. Tube expansion allowances exist in __________ heat exchanger.
a. Multipass fixed tube sheet
b. U-tube
c. Single pass fixed tube sheet
d. None of these
Q. Fruit juice (a heat sensitive material) can be concentrated in a __________ evaporator.
a. Long tube
b. Falling film
c. High pressure
d. None of these
Q. Dropwise condensation occurs on __________ surfaces.
a. Clean and dirt free
b. Smooth clean
c. Contaminated cooling
d. Polished
Q. In a backward feed multiple effect evaporator
a. Feed is introduced in the first effect
b. Feed flows from low pressure to high pressure
c. No pumps are required between successive effects
d. None of these
Q. For a given ambient air temperature with increase in the thickness of insulation of a hotcylindrical pipe, the rate of heat loss from the surface would
a. Decrease
b. Increase
c. First decrease and then increase
d. First increase and then decrease
Q. The type of liquor circulation system to be ' employed in evaporators (viz. natural or forced circulation) is determined mainly by the __________ of the liquid.
a. Viscosity
b. Density
c. Thermal conductivity
d. Corrosive nature
Q. 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)
Q. In case of __________ boiling, the bubbles formed on a submerged hot surface getabsorbed in the mass of the liquid.
a. Nucleate
b. Pool
c. Low pressure
d. None of these
Q. The separation of liquid droplets from the vapor is done by a/an __________, in the evaporators.
a. Steam ejector
b. Entrainment separator
c. Compressor
d. Vacuum pump