Air enters a compressor at ambient conditions of 100 kPa and 23 °C and leaves at 800 kPa. Heat is lost from the compressor in the amount of 120 kJ/kg with a boundary temperature of 40 °C. The air experiences an entropy decrease of 0.4 kJ/kg-K. Assume constant specific heats (cv = 0.721 kJ/kg·K; c, = 1.005 kJ/kg-K). The gas constant for air is 0.287 kJ/kg-K. Determine: a) Three valid assumptions (besides constant specific heats) b) Exit temperature of air (°C) c) Entropy generation during this process (kJ/kg-K)

Air enters a compressor at ambient conditions of 100 kPa and 23 °C and leaves at 800 kPa. Heat is lost from the compressor in the amount of 120 kJ/kg with a boundary temperature of 40 °C. The air experiences an entropy decrease of 0.4 kJ/kg-K. Assume constant specific heats (cv = 0.721 kJ/kg·K; c, = 1.005 kJ/kg-K). The gas constant for air is 0.287 kJ/kg-K. Determine: a) Three valid assumptions (besides constant specific heats) b) Exit temperature of air (°C) c) Entropy generation during this process (kJ/kg-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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