A combined gas-steam power plant generates a net power output of 350 MW. The pressure ratio of the gas-turbine cycle is 10. Air enters the compressor at 310 K and the turbine at 1300 K. The combustion gases leaving the gas turbine are used to heat the steam at 10 MPa to 420°C in a heat exchanger. The combustion gases leave the heat exchanger at 460 K. An open feedwater heater incorporated with the steam cycle operates at a pressure of 1 MPa. The condenser pressure is 10 kPa. Assuming all the compression and expansion processes to be isentropic, determine (a) the mass flow rate ratio of air to steam, (b) the required rate of heat input in the combustion chamber (c) the thermal efficiency of the combined cycle. Assume variable specific heats.

A combined gas-steam power plant generates a net power output of 350 MW. The pressure ratio of the gas-turbine cycle is 10. Air enters the compressor at 310 K and the turbine at 1300 K. The combustion gases leaving the gas turbine are used to heat the steam at 10 MPa to 420°C in a heat exchanger. The combustion gases leave the heat exchanger at 460 K. An open feedwater heater incorporated with the steam cycle operates at a pressure of 1 MPa. The condenser pressure is 10 kPa. Assuming all the compression and expansion processes to be isentropic, determine (a) the mass flow rate ratio of air to steam, (b) the required rate of heat input in the combustion chamber (c) the thermal efficiency of the combined cycle. Assume variable specific heats.

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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