The exergy destruction for each of the processes of the cycle
Answer to Problem 147P
The exergy destruction associated with process 1-2 is
The exergy destruction associated with process 5-3 is
The exergy destruction associated with process 3-4 is
The exergy destruction associated with process 6-1 is
The exergy destruction associated at regenerator is
Explanation of Solution
Draw the
Write the expression for the temperature and pressure relation for the isentropic process 1-2.
Here, the pressure ratio is
Write the expression for the efficiency of the compressor
Here, the specific heat at constant pressure is
Write the expression for the temperature and pressure relation ratio for the expansion process 4-5s.
Write the expression for the efficiency of the turbine
Apply first law to the heat exchanger.
Write the expression for the net work done per kg for the Brayton cycle with regeneration
Here, the specific heat at constant pressure is
Write the expression of heat addition to the regenerative Brayton cycle
Write the expression for rate of heat rejection in the regenerative Brayton cycle
Write the expression for the exergy destruction during the process of as steam from an inlet to exit state.
Write the expression of exergy destruction for process 1-2
Here, pressure at state 2 is
Write the expression of exergy destruction for process 5-3
Here, pressure at state 5 is
Write the expression of exergy destruction for process 3-4
Here, pressure at state 7 is
Write the expression of exergy destruction for process 6-1
Here, pressure at state 10 is
Write the expression of exergy destruction for regenerator
Conclusion:
Substitute
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The cold airstream
Substitute
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Substitute
Thus, the exergy destruction associated with process 1-2 is
Here,
Substitute
Thus, the exergy destruction associated with process 5-3 is
Substitute
Thus, the exergy destruction associated with process 3-4 is
Here,
Substitute
Thus, the exergy destruction associated with process 6-1 is
Substitute
Thus, the exergy destruction associated at regenerator is
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Chapter 9 Solutions
Thermodynamics: An Engineering Approach
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