A steam plant (Figure 1) operates on the reheat-regenerative Rankine


cycle with one direct contact feed heater and one surface contact feed heater. The boiler pressure is 150 bar and the superheat temperature is 600 °C. The reheat pressure is 40 bar and the condenser pressure is 0.1 bar.

FIGURE: http://tinypic.com/r/2h7pcpd/8


Steam is bled from the exit of the HP turbine for the surface contact feed heater; the remaining steam being reheated. The condensed bled steam (saturated water at 40 bar) is pumped into the feed water upstream of the feed heater at a pressure of 150 bar. Steam, at a
pressure of 5 bar, is bled from the LP turbine for the direct contact feed heater. The feed water leaves the feed heater as saturated water.
Assume work of the pumps is negligible, and the isentropic efficiency of the turbine stages is 80%.

(a) Draw the process on T-s diagram. [4 Marks]

(b) Identify all the points of the cycle and calculate the thermal efficiency of the plant. [29 Marks]

thanks for your help.