Consider an actual vapor-compression refrigeration cycle. R-134a enters the compressor as superheated vapor at 0.18 MPa and -10°C at a rate of 0.055 kg/s, and it leaves at 1.2 MPa and 60°C. The refrigerant is cooled in the condenser to 42°C and 1.15 MPa, and it is throttled to 0.22 MPa. Determine the rate of heat addition to the evaporator, in kW.

Consider an actual vapor-compression refrigeration cycle. R-134a enters the compressor as superheated vapor at 0.18 MPa and -10°C at a rate of 0.055 kg/s, and it leaves at 1.2 MPa and 60°C. The refrigerant is cooled in the condenser to 42°C and 1.15 MPa, and it is throttled to 0.22 MPa. Determine the rate of heat addition to the evaporator, in kW.

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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