A steam power plant with an installed capacity of 49747
kW operates on a side cycle. The boiler operates at a pressure of
10.86 atm (= 1100 kPa), while the condenser operates at a pressure
of 1.23 atm (= 125 kPa). To reduce the problem of corrosion in the
turbine, an engineer makes the following
modifications:
Heating in the boiler (isobaric) is continued until the
steam becomes superheated at a temperature of 300 ° C, then it is
expanded through the turbine (isentropic) until the pressure drops
to 1.23 atm, then flows into the condenser. The condition of the
fluid exiting the condenser and entering the boiler remains the
same.
a. Determine the fraction of water in the turbine exit
steam before and after modification!
b. Calculate the thermal efficiency of the power plant
before and after modification!
c. What is your comment on the results of points a and
b?