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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.

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:

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

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

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