A two-stage refrigeration system operates with ammonia refrigerant flowing at the rate of 15 kg/min through the evaporator. The saturation temperature in the condenser and evaporator units have been noted to be 40⁰C and - 15⁰C respectively. If the system has intercooling by liquid refrigerant at 4.25 bar, determine (a) The capacity and COP of the system. (b) How will these parameters be affected if the compression is carried out in a single stage unit ; the operating temperature limits remaining the same? Use the p-h chart and property tables for saturated ammonia refrigerant

A two-stage refrigeration system operates with ammonia refrigerant flowing at the rate of 15 kg/min through the evaporator. The saturation temperature in the condenser and evaporator units have been noted to be 40⁰C and - 15⁰C respectively. If the system has intercooling by liquid refrigerant at 4.25 bar, determine (a) The capacity and COP of the system. (b) How will these parameters be affected if the compression is carried out in a single stage unit ; the operating temperature limits remaining the same? Use the p-h chart and property tables for saturated ammonia refrigerant

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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