A controlled-temperature storage room is maintained at the desired temperature by an R-134a refrigeration unit with evaporator and condenser temperatures of –20oC and 40oC respectively. Sketch a fully labelled-diagram of the cycle on pressure-enthalpy co-ordinates. Use the combination of tables and the superheated region for refrigerant R-134a to answer this question.

A controlled-temperature storage room is maintained at the desired temperature by an R-134a refrigeration unit with evaporator and condenser temperatures of –20oC and 40oC respectively. Sketch a fully labelled-diagram of the cycle on pressure-enthalpy co-ordinates. Use the combination of tables and the superheated region for refrigerant R-134a to answer this question.

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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