One technique for operating a steam turbine in part-load power output is to throttle the steam to a lower pressure before it enters the turbine. The steam line conditions are 200 lbf/in 2, 600 F, and the turbine exhaust pressure is fixed at 1 lbf/in 2. Assuming the expansion inside the turbine to be reversible and adiabatic, determine
a. The full-load specific work output of the turbine
b. The pressure the steam must be throttled to for 80% of full-load output
c. Show both processes in a T–s diagram.