The refrigerant R-134a enters the compressor of a refrigeration machine at a pressure of 140kPa and a temperature of -10°C, and exits at a pressure of 1MPA. The volumetric flow of the refrigerant entering the compressor is 0.23m3/minute. The refrigerant enters the throttling valve at 0.95MPA pressure and 30 °C, and exits the evaporator as saturated steam at -18 °C. The adiabatic efficiency of the compressor is 78%. Show the cycle in the T-s diagram. Also, a) The power required to operate the compressor, b) The heat withdrawn from the cooled environment in unit time, COPSM=? c) Calculate how much the pressure of the refrigerant drops between the evaporator and the compressor and how much the heat gain is.

The refrigerant R-134a enters the compressor of a refrigeration machine at a pressure of 140kPa and a temperature of -10°C, and exits at a pressure of 1MPA. The volumetric flow of the refrigerant entering the compressor is 0.23m3/minute. The refrigerant enters the throttling valve at 0.95MPA pressure and 30 °C, and exits the evaporator as saturated steam at -18 °C. The adiabatic efficiency of the compressor is 78%. Show the cycle in the T-s diagram. Also, a) The power required to operate the compressor, b) The heat withdrawn from the cooled environment in unit time, COPSM=? c) Calculate how much the pressure of the refrigerant drops between the evaporator and the compressor and how much the heat gain is.

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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