Heat Transfer

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

D/5 and D

[B].

D/2 and 2 D

[C].

D/4 and 2 D

[D].

D and 2 D

Answer: Option A

Explanation:

No answer description available for this question.

Question: Open pan evaporators are preferred to be used, when the solution to be concentrated is
[A].

scaling

[B].

highly viscous

[C].

corrosive

[D].

salty

Answer: Option B

Explanation:

No answer description available for this question.

Question: Overall thermal resistance for conductive heat transfer through a series of flat resistances is equal to the
[A].

maximum resistance in the series.

[B].

sum of all resistances.

[C].

average of all resistances.

[D].

minimum resistance presents in the series.

Answer: Option B

Explanation:

No answer description available for this question.

Question: LMTD correction factor which is to be applied for a cross-flow heat exchanger increases with increase in the number of shell passes. Its value for a single pass cross flow heat exchanger is
[A].

0

[B].

1

[C].

>1

[D].

<1

Answer: Option D

Explanation:

No answer description available for this question.

Question: In a shell and tube heat exchanger, the shell side fluid velocity can not be changed by changing the
[A].

tube layout

[B].

tube diameter

[C].

tube pitch

[D].

no. of baffles

Answer: Option B

Explanation:

No answer description available for this question.

Question: In case of __________ boiling, the liquid temperature is below the saturation temperature and the boiling takes place in the vicinity of the heated surface.
[A].

nucleate

[B].

local

[C].

pool

[D].

saturated

Answer: Option B

Explanation:

No answer description available for this question.

Question: Evaporation of 1kg of water from a solution in a single effect evaporator requires about __________ kg of steam.
[A].

0.4 – 0.6

[B].

1-1.3

[C].

1.8-2

[D].

2 – 2.4

Answer: Option B

Explanation:

No answer description available for this question.

Question: 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].

Calenderia vertical tube evaporator

Answer: Option C

Explanation:

No answer description available for this question.

Question: Black liquor generated during paper manufacture is concentrated in a
[A].

single effect evaporator.

[B].

single effect evaporator followed by a crystalliser.

[C].

multiple effect evaporator.

[D].

multiple effect evaporators followed by a crystalliser.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Forced circulation evaporators are normally used for concentrating liquids having
[A].

scaling characteristics

[B].

high viscosity

[C].

both(a) & (b)

[D].

neither (a) nor (b)

Answer: Option C

Explanation:

No answer description available for this question.