Top 1000+ Solved Heat Transfer (HT) MCQ Questions Answer
Q. A dilute aqueous solution is to be concentrated in an evaporator system. High pressure steam is available. Multiple effect evaporator system is employed, because
a. Total heat transfer area of all the effects is -less than that in a single effect evaporator system
b. Total amount of vapor produced per Kg of feed steam in a multiple effect system is much higher than in a single effect
c. Boiling point elevation in a single effect system is much higher than that in any effect in a multi-effect system
d. Heat transfer co-efficient in a single effect is much lower than that in any effect in a multieffect system
Q. In a boiling curve, the peak heat flux is called the __________ point.
a. Nusselt
b. Leidenfrost
c. Boiling
d. Burnout
Q. Film condensation is promoted on a/an __________ surface.
a. Oily
b. Coated
c. Clean & smooth
d. Dirty
Q. According to Reynolds analogy, Stanton number is equal to (where, f = Fanning frictionfactor)
a. 2f
b. f
c. f/2
d. f/4
Q. In forced circulation, the heating element is injected
a. Internally
b. Externally
c. Both (A) and (A)
d. Neither (A) nor (B)
Q. Pick out the wrong statement.
a. The condensing film co-efficient is about 3 times lower for vertical condenser as compared to the equivalent horizontal condenser for identical situation
b. Film co-efficient for vaporisation decreases as a result of vapor binding
c. In industrial practice, sub-cooling of condensate is required, when the condensate is a volatile liquid and is to be transferred for storage
d. Overall heat transfer co-efficient in a heat exchanger is controlled by the value of the film coefficient, which is higher
Q. Viscous & heat sensitive liquids are concentrated in __________ evaporators.
a. Open pan
b. Long tube
c. Agitated film
d. None of these
Q. When does the heat generated by fluid friction becomes appreciable compared to the heattransferred between the fluids?
a. At high fluid velocity
b. At low velocity
c. When fluid flows past a smooth surface
d. None of these
Q. During crystallisation, formation of crystal can occur in __________ solution only.
a. Saturated
b. Supersaturated
c. Under-saturated
d. All (A), (B) and (C)