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°C condensing temperature and 5°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°C, and will enter the compressor at a temperature of 13°C. Assume a compressor volumetric efficiency of 70 per cent. Assume frictionless flow. Calculate the refrigerating capacity in kW for a system equipped with this compressor. Ans. 40.96 kW

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°C condensing temperature and 5°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°C, and will enter the compressor at a temperature of 13°C. Assume a compressor volumetric efficiency of 70 per cent. Assume frictionless flow. Calculate the refrigerating capacity in kW for a system equipped with this compressor. Ans. 40.96 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

Chapter40: Typical Operating Conditions

Section: Chapter Questions

Problem 9RQ: The evaporator design temperature may in some cases operate at a slightly ____(higher or lower)...

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