An ammonia refrigeration compressor takes its suction from the evaporator at a temperature of -20oF (-28.9oC) and a quality of 95%. The compressor discharges at a pressure of 100 psi (689.5 kPa), liquid ammonia leaves condenser at 50oF (10oC). Properties of Ammonia: At 689.6 kPa (Tsat = 13.3oC) h = 1,568 kJ/kg; s = 5.7676 kJ/kg.K At 10oC: hf = 246.531 kJ/kg At -28.9oC by interpolation hf = 68.5 kJ/kg; hg = 1424.5 kJ/kg sf = 0.49366; sg = 6.0452 Find the heat absorbed by the evaporator in kJ/kg.

An ammonia refrigeration compressor takes its suction from the evaporator at a temperature of -20oF (-28.9oC) and a quality of 95%. The compressor discharges at a pressure of 100 psi (689.5 kPa), liquid ammonia leaves condenser at 50oF (10oC). Properties of Ammonia: At 689.6 kPa (Tsat = 13.3oC) h = 1,568 kJ/kg; s = 5.7676 kJ/kg.K At 10oC: hf = 246.531 kJ/kg At -28.9oC by interpolation hf = 68.5 kJ/kg; hg = 1424.5 kJ/kg sf = 0.49366; sg = 6.0452 Find the heat absorbed by the evaporator in kJ/kg.

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

Chapter45: Domestic Refrigerators And Freezers

Section: Chapter Questions

Problem 20RQ: Welded ______sealed compressors are normally used in household refrigerators.

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Welded ______sealed compressors are normally used in household refrigerators.
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