1. A device with refrigerant-134a as the working fluid as illustrated in figure attached is used to keep a room at 26°C by rejecting the waste heat to the outdoor air at 34°C. The room gains heat from various sources amounting to 15 kW. The refrigerant enters the compressor at 500 kPa as a saturated vapor at a rate of 1000 L/min and leaves at 1200 kPa and 50°C. Determine (a) the mass flow rate of the refrigerant (b) the actual COP (c) the maximum COP (d) the minimum mass flow rate of the refrigerant for the same refrigeration load. 2 Condenser Expansion valve Compressor Evaporator a 1.2 MPa 50°C 500 kPa sat. vap.

1. A device with refrigerant-134a as the working fluid as illustrated in figure attached is used to keep a room at 26°C by rejecting the waste heat to the outdoor air at 34°C. The room gains heat from various sources amounting to 15 kW. The refrigerant enters the compressor at 500 kPa as a saturated vapor at a rate of 1000 L/min and leaves at 1200 kPa and 50°C. Determine (a) the mass flow rate of the refrigerant (b) the actual COP (c) the maximum COP (d) the minimum mass flow rate of the refrigerant for the same refrigeration load. 2 Condenser Expansion valve Compressor Evaporator a 1.2 MPa 50°C 500 kPa sat. vap.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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