Consider a combined gas-steam power plant that has a net power output of 600 MW. The pressure ratio of the gas turbine cycle is 16. Air enters the compressor at 300 K and the turbine at 1600 K. The combustion gases leaving the gas turbine are used to heat the steam to 400oC at 10 MPa in a heat exchanger. The combustion gases leave the heat exchanger at 400 K. An open feed water heater incorporated with the steam cycle operates at a pressure of 0.6 MPa. The condenser pressure is 15 kPa. Assuming all the compression and expansion processes to be isentropic, determine
(a) The mass flow rate of steam and
(b) The thermal efficiency (ηth) of the combined cycle.