Engineering Thermodynamics (3131905) MCQs

MCQs of Refrigeration Cycles

Showing 21 to 30 out of 39 Questions
21.

In vapour compression refrigeration system, the condition of refrigerant after expansion valve

(a)

high pressure, high temperature, vapour refrigerant

(b)

high pressure, high temperature, liquid refrigerant

(c)

low pressure, low temperature, liquid refrigerant

(d)

low pressure, low temperature, vapour refrigerant

Answer:

Option (c)

22.

For an expansion device, which of the following is true?

(a)

it increases the pressure of refrigerant

(b)

it regulates the flow of refrigerant to evaporator

(c)

it increases the temperature of refrigerant

(d)

none of the mentioned

Answer:

Option (b)

23.

Which of the following operations occur in a vapour refrigeration cycle?

(a)

compression

(b)

cooling and condensing

(c)

expansion and evaporation

(d)

all of the mentioned

Answer:

Option (d)

24.

Why is wet compression not preferred

(a)

the liquid refrigerant can be trapped in the head of cylinder

(b)

this may damage the valves or cylinder head

(c)

liquid refrigerant can wash away the lubricating oil thus accelerating wear

(d)

all of the mentioned

Answer:

Option (d)

25.

In the cooling and condensing, the correct sequence of processes is

(a)

desuperheated-condensed-saturated liquid

(b)

desuperheated-saturated liquid-condensed

(c)

condensed-desuperheated-saturated liquid

(d)

saturated liquid-condensed-desuperheated

Answer:

Option (a)

26.

The evaporation process is a

(a)

constant volume reversible process

(b)

constant pressure reversible process

(c)

adiabatic throttling process

(d)

Isentropic process

Answer:

Option (b)

27.

Which of the following is recommended in a refrigeration cycle?

(a)

superheating of vapour

(b)

subcooling of liquid

(c)

both superheating of vapour and subcooling of liquid

(d)

wet compression

Answer:

Option (c)

28.

The reversed heat engine takes heat from a ___ temperature body, then discharges it to a ___ temperature body and ___ an inward flow of network.

(a)

high, low, receives

(b)

low, high, receives

(c)

high, low, gives

(d)

low, high, gives

Answer:

Option (b)

29.

An example of reversed heat engine is

(a)

heat pump

(b)

refrigerator

(c)

compressor

(d)

both heat pump and refrigerator

Answer:

Option (d)

30.

The coefficient of performance for Carnot refrigerator is

(a)

TLTH-TL

(b)

THTH-TL

(c)

TLTH+TL

(d)

TLTL-TH

Answer:

Option (a)

Showing 21 to 30 out of 39 Questions