Superheated steam at \(580^{\circ} \mathrm{F}\) and \(500 \mathrm{psia}\) is expanded across a turbine, as shown in Figure 10.31, to \(540^{\circ} \mathrm{F}\) and 400 psia. \(0.9 \mathrm{~kW}\) of shaft work is produced. The turbine exhaust is cooled by a \(77^{\circ} \mathrm{F}\) reservoir to its dew point at 400 psia.

Determine the:

(a) Flowrate of steam in \(\mathrm{lb} / \mathrm{hr}\)

(b) Isentropic efficiency of the turbine

(c) Lost work

(d) Thermodynamic efficiency

Figure 10.31:-

Steam Figure 10.31 Turbine and cooler. 77F