6.69 WP Refrigerant 134a is compressed from 2 bar, saturated vapor, to 10 bar, 90°℃ in a compressor operating at steady state. The mass flow rate of refrigerant entering the compressor is 7 kg/min, and the power input is 10.85 kW. Kinetic and potential energy effects can be neglected. a. Determine the rate of heat transfer, in kW. b. If the heat transfer occurs at an average surface temperature of 50°C, determine the rate of entropy production, in kW/K. c. Determine the rate of entropy production, in kW/K, for an enlarged control volume that includes the compressor and its im- mediate surroundings such that the heat transfer occurs at 300 K.

6.69 WP Refrigerant 134a is compressed from 2 bar, saturated vapor, to 10 bar, 90°℃ in a compressor operating at steady state. The mass flow rate of refrigerant entering the compressor is 7 kg/min, and the power input is 10.85 kW. Kinetic and potential energy effects can be neglected. a. Determine the rate of heat transfer, in kW. b. If the heat transfer occurs at an average surface temperature of 50°C, determine the rate of entropy production, in kW/K. c. Determine the rate of entropy production, in kW/K, for an enlarged control volume that includes the compressor and its im- mediate surroundings such that the heat transfer occurs at 300 K.

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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