A refrigerating system has a load of 50 kJ/s uses ammonia as working fluid. The refrigerated space is kept at a temperature of –30°C. Condensing pressure is at 1.0 MPa. The ammonia refrigerant exits the evaporator with 5-degree superheat and at 160 kPa. Superheated refrigerant is discharged from the compressor at a temperature of 140°C. Wire drawing at the compressor suction is 5 kPa and the compressor discharge is 20 kPa. If the overall mechanical efficiency is 82%, determine the power input to the compressor.

A refrigerating system has a load of 50 kJ/s uses ammonia as working fluid. The refrigerated space is kept at a temperature of –30°C. Condensing pressure is at 1.0 MPa. The ammonia refrigerant exits the evaporator with 5-degree superheat and at 160 kPa. Superheated refrigerant is discharged from the compressor at a temperature of 140°C. Wire drawing at the compressor suction is 5 kPa and the compressor discharge is 20 kPa. If the overall mechanical efficiency is 82%, determine the power input to the compressor.

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

Chapter47: High-pressure, Low-pressure, And Absorption Chilled-water Systems

Section: Chapter Questions

Problem 13RQ: The subcooling temperature in a condenser can be measured by taking the difference between the A....

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