Refrigerant 134a enters the compressor of a vapor-compression refrigeration cycle at 150 kPa as a saturated vapor and leaves at 850 kPa. The refrigerant leaves the condenser as a saturated liquid. The rate of cooling provided by the system is 7kW. a. Determine the mass flow rate of R-134a and the cop of the cycle. b. If the condenser pressure is changed to 950 kPa, find the cop of the cycle.

Refrigerant 134a enters the compressor of a vapor-compression refrigeration cycle at 150 kPa as a saturated vapor and leaves at 850 kPa. The refrigerant leaves the condenser as a saturated liquid. The rate of cooling provided by the system is 7kW. a. Determine the mass flow rate of R-134a and the cop of the cycle. b. If the condenser pressure is changed to 950 kPa, find the cop of the 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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