Refrigerant R-134a is used in a vapor-compression refrigeration cycle as the circulating medium. The refrigerant enters the compressor at 200 kPa and -10oC and leaves it at 1MPa and 70oC. The mass flow rate through this component is 0.015kg/s, with a power input of 1kW. After the compressor, the refrigerant enters a water-cooled condenser at 1MPa and 60oC and leaves this condenser at 0.95MPa and 40oC. The condenser input and output temperatures of water are 10oC and 20oC, respectively. Based on this information, please find: a) The rate of heat transfer from the compressor. b) Mass flow rate of water through the condenser and the cooling capacity provided by watercooling

Refrigerant R-134a is used in a vapor-compression refrigeration cycle as the circulating medium. The refrigerant enters the compressor at 200 kPa and -10oC and leaves it at 1MPa and 70oC. The mass flow rate through this component is 0.015kg/s, with a power input of 1kW. After the compressor, the refrigerant enters a water-cooled condenser at 1MPa and 60oC and leaves this condenser at 0.95MPa and 40oC. The condenser input and output temperatures of water are 10oC and 20oC, respectively. Based on this information, please find: a) The rate of heat transfer from the compressor. b) Mass flow rate of water through the condenser and the cooling capacity provided by watercooling

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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