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Effect of liquid-line subcooling on refrigeration performance (vapor-compression cycle) How does subcooling of the condenser outlet liquid affect the cycle's coefficient of performance (C.O.P.)? Choose the correct option.

Q: Effect of liquid-line subcooling on refrigeration performance (vapor-compression cycle) How does subcooling of the condenser outlet liquid affect the cycle's coefficient of performance (C.O.P.)? Choose the correct option.

Approach Subcooling increases the refrigerating effect (more liquid enthalpy drop through the evaporator) without increasing compressor work significantly. Result Net effect is a higher refrigeration effect per unit work, so the C.O.P. increases.

Difficulty: Easy

does not alter C.O.P.
increases C.O.P.
decreases C.O.P.
none of these

Correct Answer: increases C.O.P.

Explanation:

Approach
Subcooling increases the refrigerating effect (more liquid enthalpy drop through the evaporator) without increasing compressor work significantly.

Result
Net effect is a higher refrigeration effect per unit work, so the C.O.P. increases.

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