An insulated turbine with an isentropic efficiency of 95% has expanded air initially at 2600 kPa and 500°C to a pressure of 250 kPa. The flow is considered steady, and the kinetic and potential energy changes are negligible. Air is assumed to be an ideal gas with constant specific heats, with Cp = 1.013 kJ/kg·°C, k = 1.395, and R = 0.287 kJ/kg·K.
Determine:
(i) The air outlet temperature,
(ii) The output work delivered by this turbine, and
(iii) The entropy generation during this expansion process.