A vapor-compression refrigeration cycle with refrigerant-134a as the working fluid is used to maintain aspace at -13°C by rejecting heat to ambient air at 27°C. R-134a enters the compressor at 100 kPasuperheated by 6.4°℃ at a rate of 0.05 kg/s. The isentropic efficiency of the compressor is 85 percent.The refrigerant leaves the condenser at 39.4ºC as a saturated liquid. Determinea) the rate of cooling providedb) the COP of the systemc) the minimum power input required

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A vapor-compression refrigeration cycle with refrigerant-134a as the working fluid is used to maintain a space at -13°C by rejecting heat to ambient air at 27°C. R-134a enters the compressor at 100 kPa superheated by 6.4°C at a rate of 0.05 kg/s. The isentropic efficiency of the compressor is 85 percent. The refrigerant leaves the condenser at 39.4°C as a saturated liquid. Determine a) the rate of cooling provided b) the COP of the system c) the minimum power input required

A vapor-compression refrigeration cycle with refrigerant-134a as the working fluid is used to maintain a space at -13°C by rejecting heat to ambient air at 27°C. R-134a enters the compressor at 100 kPa superheated by 6.4°C at a rate of 0.05 kg/s. The isentropic efficiency of the compressor is 85 percent. The refrigerant leaves the condenser at 39.4°C as a saturated liquid. Determine a) the rate of cooling provided b) the COP of the system c) the minimum power input required

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

Chapter28: Special Refrigeration Applications

Section: Chapter Questions

Problem 15RQ: Why is two-stage compression popular for extra-low-temperature refrigeration systems?

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