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1. Air enters the compressor of an idea cold air-standard Brayton cycle at 100kPa,
300K, with a mass flow rate of 5 kg/s. The compressor pressure ratio is 10, and
the turbine inlet temperature is 1300K. For k=1.4, calculate thermal efficiency of
the cycle and net work produced. Find the ideal pressure ratio that maximizes the
work produced.
2. Repeat problem 1, when the turbine and compressor each have efficiencies of
80%. Use the same pressure ratio as you derived in the problem 1. Evaluate
exergy destruction in the compressor and turbine for $T_r$ = 300K. Find and
compare the ideal pressure ratio that maximizes the net work produce.
3. Repeat problem 1 with a regenerator. The turbine and compressor each have
efficiencies of 80%, and the regenerator effectiveness is 70%.
4. Repeat problem 1 with dual-stage expansion & compression. Assume turbines
and compressors are ideal. (a) Determine the optimum pressure for inlets of the
second turbine & compressor. (b) Evaluate thermal efficiency and net work
produced.
5. Repeat problem 4 when the thermal efficiency when the isentropic efficiencies of
