A 55 kW refrigeration load is to be carried by an air refrigeration system with a discharge pressure of 1370 kPa and a refrigerator pressure of 345 kPa. Compression and expansion processes are polytropic with n-1.37. The pressure at the start of the expansion is 1344 kPa and the temperature is 32°C. Air temperature leaving the refrigerator is 0°C and entering the compressor is 5°C. Clearance for both compressor and expander is 5%. Determine the COP.

A 55 kW refrigeration load is to be carried by an air refrigeration system with a discharge pressure of 1370 kPa and a refrigerator pressure of 345 kPa. Compression and expansion processes are polytropic with n-1.37. The pressure at the start of the expansion is 1344 kPa and the temperature is 32°C. Air temperature leaving the refrigerator is 0°C and entering the compressor is 5°C. Clearance for both compressor and expander is 5%. Determine 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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Why is two-stage compression popular for extra-low-temperature refrigeration systems?
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A 55 kW refrigeration load is to be carried by an air refrigeration system with a discharge pressure of 1370 kPa and a refrigerator pressure of 345 kPa. Compression and expansion processes are polytropic with n-1.37. The pressure at the start of the expansion is 1344 kPa and the temperature is 32°C. Air temperature leaving the refrigerator is 0°C and entering the compressor is 5°C. Clearance for both compressor and expander is 5%. Determine the (b)The net work load
A 55 kW refrigeration load is to be carried by an air refrigeration system with a discharge pressure of 1370 kPa and a refrigerator pressure of 345 kPa. Compression and expansion processes are polytropic with n-1.37. The pressure at the start of the expansion is 1344 kPa and the temperature is 32°C. Air temperature leaving the refrigerator is 0°C and entering the compressor is 5°C. Clearance for both compressor and expander is 5%.Determine the (a) The piston displacement of the compressor and expander.
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