Ammonia enters the compressor of an industrial refrigeration plant at 2 bar, -10°C with a mass flow rate of 15 kg/min and is compressed to 12 bar, 140°C. Heat transfer from the compressor to its surroundings occurs at a rate of 6 kW. For steady-state operation, calculate, (a) the power input to the compressor, in kW, Answer (b) the entropy production rate, in kW/K, for a control volume encompassing the compressor and its immediate surroundings such that heat transfer occurs at 300 K.

Ammonia enters the compressor of an industrial refrigeration plant at 2 bar, -10°C with a mass flow rate of 15 kg/min and is compressed to 12 bar, 140°C. Heat transfer from the compressor to its surroundings occurs at a rate of 6 kW. For steady-state operation, calculate, (a) the power input to the compressor, in kW, Answer (b) the entropy production rate, in kW/K, for a control volume encompassing the compressor and its immediate surroundings such that heat transfer occurs at 300 K.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter4: The Second Law Of Thermodynamics

Section: Chapter Questions

Problem 53P: A copper rod of cross-sectional area 5.0 cm2 and length 5.0 m conducts heat from a heat reservoir at...

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