2. An R22 standard refrigeration system carries a refrigerating load of 82 kW. The suction and discharge pressures of the compressor are 354.3 kPa and 1460.1 kPa respectively. The liquid refrigerant is subcooled by 4• before entering the expansion valve and the vapor is superheated by 5º before entering the compressor. The twin- cylinder, single-acting efficiency, 82%; clearance volume, 6%; and mechanical efficiency, 78% compressor operates at 1680 rpm; stroke-to-bore ratio, 1.20; actual volumetric Determine (a) mass flow rate of refrigerant in kg/s (b) mass flow rate of refrigerant per ton of refrigeration in kg/s-ton (r) work on comnressor in kW

2. An R22 standard refrigeration system carries a refrigerating load of 82 kW. The suction and discharge pressures of the compressor are 354.3 kPa and 1460.1 kPa respectively. The liquid refrigerant is subcooled by 4• before entering the expansion valve and the vapor is superheated by 5º before entering the compressor. The twin- cylinder, single-acting efficiency, 82%; clearance volume, 6%; and mechanical efficiency, 78% compressor operates at 1680 rpm; stroke-to-bore ratio, 1.20; actual volumetric Determine (a) mass flow rate of refrigerant in kg/s (b) mass flow rate of refrigerant per ton of refrigeration in kg/s-ton (r) work on comnressor in kW

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

Chapter22: Condensers

Section: Chapter Questions

Problem 7RQ: When a standard-efficiency air-cooled condenser is used, the condensing refrigerant will normally be...

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