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.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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