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A Carnot heat engine receives heat at 750 K and rejects the waste heat to the environment at 300 K. The net work output of the heat engine is used to drive a Carnot refrigerator, whose COP is 6.14. If the heat removal rate from the refrigerated space is 6.6 kW, determine the rate of heat supply to the heat engine?

A Carnot heat engine receives heat at 750 K and rejects the waste heat to the environment at 300 K. The net work output of the heat engine is used to drive a Carnot refrigerator, whose COP is 6.14. If the heat removal rate from the refrigerated space is 6.6 kW, determine the rate of heat supply to the heat engine? Correct Answer 1.79 kW

W(HE) = (1 – T(L)/T(H))*Q(H) = 0.6*Q(H); W(R) = W(HE); Q(L)/COP(R) = 0.6*Q(H); ∴ Q(H) = Q(L)/(0.6*COP(R)) Rate of heat supply to the heat engine (Q(H)) = 1.79 kW.

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