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, and (c) the COP of the refrigerator. Answers: (a) 0.00644 kg/s, (b) 800 kPa, (c) 2.03 |↓ Condenser Expansion valve 120 kPa x=0.34 Evaporator M Warm environment 70°C Compressor Cold environment

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, and (c) the COP of the refrigerator. Answers: (a) 0.00644 kg/s, (b) 800 kPa, (c) 2.03 |↓ Condenser Expansion valve 120 kPa x=0.34 Evaporator M Warm environment 70°C Compressor Cold environment

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

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 2RQ: The operating condition for the single compressor in a household refrigerator is the lowest box...

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Condensers in these refrigerators are all_______cooled.
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