A gas-turbine power plant operates on the simple Brayton cycle between the
pressure limits of 100 and 800 kPa. Air enters the compressor at \(30^{\circ}
\mathrm{C}\) and leaves at \(330^{\circ} \mathrm{C}\) at a mass flow rate of \(200
\mathrm{kg} / \mathrm{s}\). The maximum cycle temperature is \(1400 \mathrm{K}\).
During operation of the cycle, the net power output is measured experimentally
to be 60 MW. Assume constant properties for air at \(300 \mathrm{K}\) with
\(c_{\mathrm{v}}=0.718 \mathrm{kJ} / \mathrm{kg} \cdot \mathrm{K}, c_{p}=\)
\(1.005 \mathrm{kJ} / \mathrm{kg} \cdot \mathrm{K}, R=0.287 \mathrm{kJ} /
\mathrm{kg} \cdot \mathrm{K}, k=1.4\)
(a) Sketch the \(T\) -s diagram for the cycle.
(b) Determine the isentropic efficiency of the turbine for these operating
conditions.
(c) Determine the cycle thermal efficiency.