Problem 7- Brayton cycle An air-standard, steady-flow Brayton cycle has a pressure ratio of 15. The minimum and maximum temperatures within the cycle are 300 K and 1000 K. The pressure at the inlet to the compressor is 100 kPa. Assume the adiabatic compressor has a 90% isentropic efficiency, and the turbine is 85% efficient compared to an isentropic one. (a) Determine the pressure and temperature of the air at the beginning of the four processes that make up the cycle. (b) Calculate the net work output of the cycle and the heat input to the air during the combustion process, both on a unit mass basis of working fluid. (c) For constant temperature heat source of 1200 K and heat sink of 290 K, is the cycle reversible? If not, determine the entropy generation of the entire cycle per unit mass of the air. Use constant properties of air (k = 1.4 and cp = 1.004 kJ/kg-K).

Problem 7- Brayton cycle An air-standard, steady-flow Brayton cycle has a pressure ratio of 15. The minimum and maximum temperatures within the cycle are 300 K and 1000 K. The pressure at the inlet to the compressor is 100 kPa. Assume the adiabatic compressor has a 90% isentropic efficiency, and the turbine is 85% efficient compared to an isentropic one. (a) Determine the pressure and temperature of the air at the beginning of the four processes that make up the cycle. (b) Calculate the net work output of the cycle and the heat input to the air during the combustion process, both on a unit mass basis of working fluid. (c) For constant temperature heat source of 1200 K and heat sink of 290 K, is the cycle reversible? If not, determine the entropy generation of the entire cycle per unit mass of the air. Use constant properties of air (k = 1.4 and cp = 1.004 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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