Applying the Exergy Balance: Control VolumesA gas turbine

Chapter 7, Problem 86P

(choose chapter or problem)

A gas turbine operating at steady state is shown in Fig. P7.86. Air enters the compressor with a mass flow rate of 5 kg/s at 0.95 bar and \(22^{\circ} \mathrm{C}\) and exits at 5.7 bar. The air then passes through a heat exchanger before entering the turbine at 1100 K, 5.7 bar. Air exits the turbine at 0.95 bar. The compressor and turbine operate adiabatically and the effects of motion and gravity can be ignored. The compressor and turbine isentropic efficiencies are 82 and 85%, respectively. Using the ideal gas model for air, determine, each in kW,

(a) the net power developed.

(b) the rates of exergy destruction for the compressor and turbine.

(c) the net rate exergy is carried out of the plant at the turbine exit, \(\left(\dot{\mathrm{E}}_{\mathrm{f4}}-\dot{\mathrm{E}}_{\mathrm{fl}}\right)\).

Let \(T_0\) = \(22^{\circ} \mathrm{C}\), \(p_0\) = 0.95 bar.