A combined cycle power plant has a total net power output of 286 MW. Air enters...

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A combined cycle power plant has a total net power output of 286 MW. Air enters the compressor of the Brayton cycle at 100 KPa and 290 K, where it is compressed to 2140 kPa with a compressor that has an efficiency of 88%. The air is burned with methane, which enters at 298 K, in an adiabatic combustor and the temperature exiting the combustor is 1640 K. The product gases exiting the combustor enter the turbine, where they are expanded back to 100 kPa with a turbine efficiency of 90%. The product gases then pass through the HRSG, where they are used to provide heat to the boiler of the Rankine cycle. The product gases exit the HRSG at 380 K. For the Rankine cycle, the steam is heated to 6 MPa and 600 ℃ in the boiler, the isentropic efficiency of the turbine is 91%, the condenser pressure is 10 kPa and the pump efficiency is 72%. Determine: 1. The temperature of the air after compression, in K. 2. The equivalence ratio in the combustor. 3. The mass fractions of the product gas mixture leaving the combustor. 4. The average specific heat capacity of the product gas mixture. 5. The average ratio of specific heats of the product gas mixture. 6. The temperature of the product gas mixture exiting the turbine. 7. The mass flow rate of air. 8. The mass flow rate of fuel. 9. The mass flow rate of water through the Rankine cycle. 10. The overall efficiency of the plant. A combined cycle power plant has a total net power output of 286 MW. Air enters the compressor of the Brayton cycle at 100 KPa and 290 K, where it is compressed to 2140 kPa with a compressor that has an efficiency of 88%. The air is burned with methane, which enters at 298 K, in an adiabatic combustor and the temperature exiting the combustor is 1640 K. The product gases exiting the combustor enter the turbine, where they are expanded back to 100 kPa with a turbine efficiency of 90%. The product gases then pass through the HRSG, where they are used to provide heat to the boiler of the Rankine cycle. The product gases exit the HRSG at 380 K. For the Rankine cycle, the steam is heated to 6 MPa and 600 ℃ in the boiler, the isentropic efficiency of the turbine is 91%, the condenser pressure is 10 kPa and the pump efficiency is 72%. Determine: 1. The temperature of the air after compression, in K. 2. The equivalence ratio in the combustor. 3. The mass fractions of the product gas mixture leaving the combustor. 4. The average specific heat capacity of the product gas mixture. 5. The average ratio of specific heats of the product gas mixture. 6. The temperature of the product gas mixture exiting the turbine. 7. The mass flow rate of air. 8. The mass flow rate of fuel. 9. The mass flow rate of water through the Rankine cycle. 10. The overall efficiency of the plant.