3. A refrigerator uses refrigerant-134a as the working fluid and operates on the ideal vapor- compression refrigeration cycle except for the compression process. The refrigerant enters the evaporator at 120 kPa with a quality of 34 percent and leaves the compressor at 70°C. If the compressor consumes 450 W of power, determine a) the mass flow rate of the refrigerant, b) the condenser pressure, c) the COP of the refrigerator.

3. A refrigerator uses refrigerant-134a as the working fluid and operates on the ideal vapor- compression refrigeration cycle except for the compression process. The refrigerant enters the evaporator at 120 kPa with a quality of 34 percent and leaves the compressor at 70°C. If the compressor consumes 450 W of power, determine a) the mass flow rate of the refrigerant, b) the condenser pressure, c) the COP of the refrigerator.

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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