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A 10-kW cooling load (i.e., ?̇ L) is to be served by operating an ideal vapor-compression refrigeration cycle with its evaporator at 400 kPa and its condenser at 800 kPa. If the compressor’s isentropic efficiency is set at 68%, determine
(a) the rate of heat rejection to the environment, in kW
(b) the COP of the refrigerator
(c) the compressor’s power requirement, in kW.
Disregard any heat loss in the expansion valve and compressor as well as the change in potential and kinetic energy of the refrigerant in any part of the cycle.
Use g = 9.81 m/s2 or 32.2 ft/s2 , T(K)=T(°C)+273 and T(R)=T(°F)+460, where applicable.
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