Refrigerant 134a enters a compressor of a vapour compression of a refrigeration cycle at 120Kpa as a saturated vapour and leaves at 900 Kpa and 75oc. The refrigerant leaves the condenser as a saturated liquid. The rate of cooling provided by the system is 18000 Btu/hr. Determine (1) Mass flow rate of R134a (2) The Cop of the cycle (3) Also determine the Cop of the cycle if the expansion valve is replaced by an isentropic turbine. Do you recommend such a replacement for the refrigeration system? (4) Determine the Cop if the evaporator pressure is 160Kpa and otheer values remains the same. (5) Determine the Cop if the condenser pressure is 800 Kpa and other values remain the same.

Refrigerant 134a enters a compressor of a vapour compression of a refrigeration cycle at 120Kpa as a saturated vapour and leaves at 900 Kpa and 75oc. The refrigerant leaves the condenser as a saturated liquid. The rate of cooling provided by the system is 18000 Btu/hr. Determine (1) Mass flow rate of R134a (2) The Cop of the cycle (3) Also determine the Cop of the cycle if the expansion valve is replaced by an isentropic turbine. Do you recommend such a replacement for the refrigeration system? (4) Determine the Cop if the evaporator pressure is 160Kpa and otheer values remains the same. (5) Determine the Cop if the condenser pressure is 800 Kpa and other values remain the same.

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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