An industrial plant has available a 4 cylinder, 76-mm bore by 102-mm stroke, 800 rpm, single-acting compressor for use with Refrigerant 12. Proposed operating conditions for the compressor are 38 degrees * C condensing temperature and 5 degrees * C evaporating temperature. It is estimated that the refrigerant will enter the expansion valve as a saturated liquid, that the vapor will leave the evaporator at a temperature of 7 degrees * C and will enter the compressor at a temperature of 13 degrees * C . Assume a compressor volumetric efficiency of 70%. Assume frictionless flow. Calculate the refrigerating capacity in kW for a system equipped with this compressor.

An industrial plant has available a 4 cylinder, 76-mm bore by 102-mm stroke, 800 rpm, single-acting compressor for use with Refrigerant 12. Proposed operating conditions for the compressor are 38 degrees * C condensing temperature and 5 degrees * C evaporating temperature. It is estimated that the refrigerant will enter the expansion valve as a saturated liquid, that the vapor will leave the evaporator at a temperature of 7 degrees * C and will enter the compressor at a temperature of 13 degrees * C . Assume a compressor volumetric efficiency of 70%. Assume frictionless flow. Calculate the refrigerating capacity in kW for a system equipped with this compressor.

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 12RQ: Compare the standard conditions of high-efficiency and standard air-cooled condensers.

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