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Question 14.6: A vapor compression heat pump consisting of an evaporator, c......

A vapor compression heat pump consisting of an evaporator, compressor, condenser, and expansion valve is operating in the cooling mode with a COP of 3.2. The compressor input power is 12 kW. Determine the rate of useful heat production in the evaporator and the rate of heat rejection in the condenser.

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1. Rate of useful heat production in the evaporator (in cooling mode)

Qev=Pcr/COP=12/3.2=3.75 kWQ_{\mathrm{ev}}=P_{\mathrm{cr}}/\mathrm{COP}=12/3.2=3.75\,{\mathrm{kW}}

2. Rate of heat rejection in the condenser

Qc=Qev+Pcr=3.75+12=15,75 kWQ_{\mathrm{c}}=Q_{\mathrm{ev}}+P_{\mathrm{cr}}=3.75+12=15,75\,{\mathrm{kW}}

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