Chemical Engineering - Heat Transfer
Exercise :: Heat Transfer - Section 1
16.
Fouling factor
A. is a dimensionless quantity. B. does not provide a safety factor for design. C. accounts for additional resistances to heat flow. D. none of these.
Answer: Option C
Explanation:
17.
In case of vertical tube evaporator, with increase in liquor level, the overall heat transfer co-efficient
A. increases B. decreases C. is not affected D. may increase or decrease; depends on the feed
Answer: Option B
Explanation:
18.
The steam ejector is used to
A. remove condensate from the steam pipelines. B. create vacuum. C. superheat the steam. D. none of these.
Answer: Option B
Explanation:
19.
For shell and tube heat exchanger, with increasing heat transfer area, the purchased cost per unit heat transfer area
A. increases B. decreases C. remains constant D. passes through a maxima
Answer: Option D
Explanation:
20.
The thermal efficiency of a reversible heat engine operating between two given thermal reservoirs is 0.4. The device is used either as a refrigerator or as a heat pump between the same reservoirs. Then the coefficient of performance as a refrigerator (COP)R and the co-efficient of performance as a heat pump (COP)HP are
A. (COP)R = (COP)HP = 0.6 B. (COP)R = 2.5; (COP)HP = 1.5 C. (COP)R = 1.5; (COP)HP = 2.5 D. (COP)R = (COP)HP = 2.5
Answer: Option C
Explanation:
