A refrigeration system using R-12 as refrigerant consists of three evaporators of capacities 20 TR at- 5°C, 30 TR at 0°C and 10 TR at 5°C. The vapours leaving the three evaporators are dry and saturated. The system is provided with individual compressors and multiple expansion valves. The condenser temperature is 40°C and the liquid refrigerant leaving the condenser is saturated. Assuming isentropic compression in each compressor, find (a) the mass of refrigerant flowing through each evaporator, (b) the power required to drive the system, and (c) the COP. of the system.

A refrigeration system using R-12 as refrigerant consists of three evaporators of capacities 20 TR at- 5°C, 30 TR at 0°C and 10 TR at 5°C. The vapours leaving the three evaporators are dry and saturated. The system is provided with individual compressors and multiple expansion valves. The condenser temperature is 40°C and the liquid refrigerant leaving the condenser is saturated. Assuming isentropic compression in each compressor, find (a) the mass of refrigerant flowing through each evaporator, (b) the power required to drive the system, and (c) the COP. of the system.

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 9RQ: The approach temperature for the evaporator is A. the difference between the suction and head...

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