An automotive air conditioner operates on the vapor-compression refrigeration cycle with refrigerant-134a as the working fluid. The refrigerant enters the compressor at 180 kPa super- heated by 2.7°C at a rate of 0.007 kg/s and leaves the compressor at 1200 kPa and 60°C. R-134a is subcooled by 6.3°C at the exit of the condenser. Determine (a) the isentropic efficiency of the compressor, (b) the rate of cooling, and (c) the COP.

An automotive air conditioner operates on the vapor-compression refrigeration cycle with refrigerant-134a as the working fluid. The refrigerant enters the compressor at 180 kPa super- heated by 2.7°C at a rate of 0.007 kg/s and leaves the compressor at 1200 kPa and 60°C. R-134a is subcooled by 6.3°C at the exit of the condenser. Determine (a) the isentropic efficiency of the compressor, (b) the rate of cooling, and (c) the COP.

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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