QUESTION 2 Condenser Diagram 2E shows an ideal cascade vapour-compression refrigeration cycle using 11160"/nr R134a in the first cycle. The refrigerant enters the first compressor at 100kPa and the Heat- second compressor at 900kPa. Exchanger The heat-exchanger is operated at 280kPa for both #1 and #2. Both compressor stages work with an isentropic efficiency of 90% Evaporator Diagram 2E Calculate the coefficient of performance for this refrigeration cycle (18) 2 Calculate the refrigeration effect for this refngeration cycle

QUESTION 2 Condenser Diagram 2E shows an ideal cascade vapour-compression refrigeration cycle using 11160"/nr R134a in the first cycle. The refrigerant enters the first compressor at 100kPa and the Heat- second compressor at 900kPa. Exchanger The heat-exchanger is operated at 280kPa for both #1 and #2. Both compressor stages work with an isentropic efficiency of 90% Evaporator Diagram 2E Calculate the coefficient of performance for this refrigeration cycle (18) 2 Calculate the refrigeration effect for this refngeration cycle

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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