Q6) In a refrigerant 22 refrigeration system the capacity is 180 kW at a temperature of -30°C. The vapor from the evaporator is pumped by one compressor to the condensing pressure of 1500 kPa. Later the system is revised to a two-stage compression operating on the cycle shown in the Figure with intercooling but no removal of flash gas at 600 kPa. (a) Calculate the power required by the single compressor in the original system. (b) Calculate the total power required by the two compressors in the revised system. (Ans. (a) 71.23 kW and (b) 70.73 kW). Conden I500 Intercoole Eveporator Lowae compressor

Q6) In a refrigerant 22 refrigeration system the capacity is 180 kW at a temperature of -30°C. The vapor from the evaporator is pumped by one compressor to the condensing pressure of 1500 kPa. Later the system is revised to a two-stage compression operating on the cycle shown in the Figure with intercooling but no removal of flash gas at 600 kPa. (a) Calculate the power required by the single compressor in the original system. (b) Calculate the total power required by the two compressors in the revised system. (Ans. (a) 71.23 kW and (b) 70.73 kW). Conden I500 Intercoole Eveporator Lowae 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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Why is two-stage compression popular for extra-low-temperature refrigeration systems?
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