Heat Transfer

Question: Multipass heat exchangers are used
[A].

because of simplicity of fabrication.

[B].

for low heat load.

[C].

to obtain higher heat transfer co-efficient and shorter tube.

[D].

to reduce the pressure drop.

Answer: Option C

Explanation:

No answer description available for this question.

Question: In evaporators, lowering the feed temperature
[A].

increases the heating area required.

[B].

reduces the economy.

[C].

both (a) and (b).

[D].

decreases the heating area required.

Answer: Option C

Explanation:

No answer description available for this question.

Question: Increasing the liquor level in the evaporator results in the
[A].

decreased capacity.

[B].

increase in liquor film co-efficient.

[C].

decreased effect of hydrostatic head.

[D].

increased true temperature drop.

Answer: Option A

Explanation:

No answer description available for this question.

Question: In a multiple effect evaporator, the effect of boiling point elevation is to
[A].

reduce the capacity

[B].

reduce the economy

[C].

increase the economy

[D].

none of these

Answer: Option A

Explanation:

No answer description available for this question.

Question: Fqra cold viscous feed, backward feed gives __________ than forward feed.
[A].

a higher capacity

[B].

a lower capacity

[C].

lower economy

[D].

none of these

Answer: Option A

Explanation:

No answer description available for this question.

Question: Economy of an evaporator is influenced by the
[A].

steam pressure

[B].

feed temperature

[C].

number of effect

[D].

both(b) & (c)

Answer: Option D

Explanation:

No answer description available for this question.

Question: Kg of liquid evaporated per hour in an evaporator is defined as its
[A].

capacity

[B].

economy

[C].

steam load

[D].

none of these

Answer: Option A

Explanation:

No answer description available for this question.

Question: In a single effect evaporator, the economy is
[A].

1

[B].

< 1

[C].

> 1

[D].

none of these

Answer: Option B

Explanation:

No answer description available for this question.

Question: 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

Answer: Option B

Explanation:

No answer description available for this question.

Question: Heat sensitive materials can be concentrated in an evaporator employing
[A].

vacuum

[B].

high pressure

[C].

high residence time

[D].

none of these

Answer: Option A

Explanation:

No answer description available for this question.