Heat Transfer

221. In case of a multipass shell and tube heat exchanger, the temperature drop in the fluid

1. Is inversely proportional to the resistance across which the drop occurs
2. And the wall are proportional to individual resistances
3. And the wall is not related
4. None of these

View answer

222. In case of a shell and tube heat exchanger, the minimum and maximum baffle spacing is respectively (where, D = inside diameter of the shell)

1. D/5 and D
2. D/2 and 2 D
3. D/4 and 2 D
4. D and 2 D

View answer

223. In case of a super-cooled solution, which is on the verge of crystallisation, the free energy of the solution as compared to that of the solid is

1. More
2. Less
3. Same
4. More or less; depends on the nature of solution

View answer

224. In case of a vertical tube evaporator, with increase in the liquor level, the

1. Capacity of the evaporator is decreased
2. Capacity of the evaporator is increased
3. True temperature drop increases
4. Both (B) and (C)

View answer

225. In case of a vertical tube evaporator, with increase in the liquor level, the _________ is increased.

1. Velocity of circulation
2. Liquor-film co-efficient
3. Both (A) and (B)
4. Neither (A) and (B)

View answer

226. In case of evaporators, liquid entrainment results primarily due to

1. High vacuum in the evaporator
2. High evaporation rate
3. Foaming of the solution
4. High heat transfer rate

View answer

227. In case of heat flow by conduction for a cylindrical body with an internal heat source, the nature of temperature distribution is

1. Linear
2. Hyperbolic
3. Parabolic
4. None of these

View answer

228. In case of heat transfer by conduction in a hollow cylinder, _________ mean area is used to calculate the heat transfer rate.

1. Geometric
2. Arithmetic
3. Logarithmic
4. Either (A), (B) or (C)

View answer

229. In case of parallel flow heat exchanger, the lowest temperature theoretically attainable by the hot fluid is _________ the outlet temperature of the cold fluid.

1. Equal to
2. More than
3. Less than
4. Either more or less than (depending upon the fluid)

View answer

230. In case of vertical tube evaporator, with increase in liquor level, the overall heat transfer co-efficient

1. Increases
2. Decreases
3. Is not affected
4. May increase or decrease; depends on the feed

View answer