Question

0.75 kg of refrigerant-134a at 120 kPa and 20°C initially fills a piston-cylinder device. Heat is...

0.75 kg of refrigerant-134a at 120 kPa and 20°C initially fills a piston-cylinder device. Heat is now transferred to the refrigerant from a source at 150°C, and the piston which is resting on a set of stops, starts moving when the pressure inside reaches 140 kPa. Heat transfer continues until the temperature reaches 90°C. Assuming the surrounding to be at 25°C and 100 kPa, determine (a) the work done, (b) the heat transfer, (c) the exergy destroyed, and (d) the second law efficiency of this process.

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