Question

A Brayton cycle operates with regencration with air as the working fluid. Air enters the compressor at \(95 \mathrm{kPa}\) and \(290 \mathrm{~K}\) and the turbine at \(760 \mathrm{kPa}\) and \(1100 \mathrm{~K}\). Heat is transferred in the combustion region at a rate of \(75,000 \mathrm{~kJ} / \mathrm{s}\). The compressor Operates isentropically. The effectiveness of regenerator is \(80 \%\). The compressor and turbine operate is entropically. There are no pressure changes in the regenerator or combustion region. \(\mathrm{h}_{1}=290.16 \mathrm{~kJ} / \mathrm{kg}:\)

\(\mathrm{h}_{2}=526.12 \mathrm{~kJ} / \mathrm{kg}\). Determine:

a) The temperature after the turbine \((\mathrm{K})\)

b) The temperature after the regenerator and before combustion \((\mathrm{K})\)

c) The net power made (kW)

d) If the turbine had an isentropic efficiency of \(100 \%\) could the relationship of \(p y / p_{4}=p_{t} 3 / p_{n}+b e\) used and why or why not?

e) If the turbine and compressor both had an isentropic efficiency of \(100 \%\) would the net power made: a) significantly go down; b) go down; c) stay the same; d) go up; or e) significantly go up give a one sentence explanation as to why.

Answer 1