An ideal Brayton refrigeration cycle has a compressor pressure ratio of 7. At the compressor inlet, the pressure and temperature of the entering air are 22 lbf/in.² and 450°R, respectively. The temperature at the inlet of the turbine is 680°R. The compressor and turbine have esentropic efficiencies of 75% and 0.88%, respectively. For a refrigerating capacity of 16.5 tons, determine: (a) the mass flow rate of the refrigerant, in lb/min. (b) the net power input, in Btu/min. (c) the coefficient of performance.

An ideal Brayton refrigeration cycle has a compressor pressure ratio of 7. At the compressor inlet, the pressure and temperature of the entering air are 22 lbf/in.² and 450°R, respectively. The temperature at the inlet of the turbine is 680°R. The compressor and turbine have esentropic efficiencies of 75% and 0.88%, respectively. For a refrigerating capacity of 16.5 tons, determine: (a) the mass flow rate of the refrigerant, in lb/min. (b) the net power input, in Btu/min. (c) the coefficient of performance.

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

Chapter41: Troubleshooting

Section: Chapter Questions

Problem 8RQ: When the outside ambient air temperature is 90F, the temperature of the condensing refrigerant in a...

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