A refrigerator using R-134a is located in a 20°C room. Consider an ideal cycle, but the compressor is neither adiabatic nor reversible. Saturated vapor at -20°C enters the compressor, and the R-134a exits the compressor at 1017 kPa. The mass flowrate of refrigerant around the cycle is 0.2 kg/s and the COP is measured and found to be 2.3. Draw the T-s diagram, indicating the temperature and pressure lines. Determine the temperature at the outlet of the condenser and the power input to the compressor in kW. Determine, the temperature at the exit of the compressor, if the heat that the compressor losses is 11.53 kJ/kg. Note: Perform energy balance. For this part, take 1017 kPa as 1000 kPa.

A refrigerator using R-134a is located in a 20°C room. Consider an ideal cycle, but the compressor is neither adiabatic nor reversible. Saturated vapor at -20°C enters the compressor, and the R-134a exits the compressor at 1017 kPa. The mass flowrate of refrigerant around the cycle is 0.2 kg/s and the COP is measured and found to be 2.3. Draw the T-s diagram, indicating the temperature and pressure lines. Determine the temperature at the outlet of the condenser and the power input to the compressor in kW. Determine, the temperature at the exit of the compressor, if the heat that the compressor losses is 11.53 kJ/kg. Note: Perform energy balance. For this part, take 1017 kPa as 1000 kPa.

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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