The high temperature evaporator (Refrigeration capacity 5 TR) of a multi-evaporator VCR system, working with ammonia, is operating at -6°C and the low temperature evaporator (Refrigeration capacity 10 TR) is operating at -34°C. The condenser pressure is 10.99 bar. The system using individual expansion valves for each evaporator. Assuming saturated conditions at the exit of evaporators and condenser and isentropic compression: a) Find the required power input and COP if a single compressor is used. b) If individual compressors are used for both stage find the power input and COP. c) Compare both cases.

The high temperature evaporator (Refrigeration capacity 5 TR) of a multi-evaporator VCR system, working with ammonia, is operating at -6°C and the low temperature evaporator (Refrigeration capacity 10 TR) is operating at -34°C. The condenser pressure is 10.99 bar. The system using individual expansion valves for each evaporator. Assuming saturated conditions at the exit of evaporators and condenser and isentropic compression: a) Find the required power input and COP if a single compressor is used. b) If individual compressors are used for both stage find the power input and COP. c) Compare both cases.

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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