An ammonia vapour-compression refrigerator operates between an evaporator pressure of 2.077 bar and a condenser pressure of 12.37 bar. The following cycles are to be compared; in each case there is noundercooling in the condenser, and isentropic compression may be assumed:（ii）the vapour has a dryness fraction of 0.9 at entry to the compressor;(iii) the vapour is dry saturated at entry to the compressor;the vapour has 5 K of superheat at entry to the compressor. In each case calculate the COPrer and the refrigerating effect per unit mass. What would be the COPrer ofa reversed Carnot cycle operating between the same saturation temperatures?

An ammonia vapour-compression refrigerator operates between an evaporator pressure of 2.077 bar and a condenser pressure of 12.37 bar. The following cycles are to be compared; in each case there is noundercooling in the condenser, and isentropic compression may be assumed:（ii）the vapour has a dryness fraction of 0.9 at entry to the compressor;(iii) the vapour is dry saturated at entry to the compressor;the vapour has 5 K of superheat at entry to the compressor. In each case calculate the COPrer and the refrigerating effect per unit mass. What would be the COPrer ofa reversed Carnot cycle operating between the same saturation temperatures?

Refrigeration and Air Conditioning Technology (MindTap Course List)

8th Edition

ISBN:9781305578296

Author:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Publisher:John Tomczyk, Eugene Silberstein, Bill Whitman, Bill Johnson

Chapter22: Condensers

Section: Chapter Questions

Problem 7RQ: When a standard-efficiency air-cooled condenser is used, the condensing refrigerant will normally be...

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