A gas turbine power plant burns ethane gas in excess air, producing 250 MW of output...

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A gas turbine power plant burns ethane gas in excess air, producing 250 MW of output power. It employs a single- shaft gas turbine reheat cycle and is characterised by the following data: (i) Compressor pressure ratio = 30 Ambient conditions = 1 bar & 300 K Isentropic efficiency of compressor = 0.9 Isentropic efficiencies of turbines = 0.9 each Inlet temperature of both turbines = 1800 K Pressure loss in both combustors pressure 3% of entry Turbine exhaust pressure for second turbine = 1.0 bar Combustion efficiency of both combustors = 0.96 Lower calorific value of fuel = 42 MJ/kg Take Cp of air to be 1.005 kJ.kg-1K-1 & Cp of the products to be 1.16 kJ.kg-1K-1. You can assume the combustion is isobaric and optimal pressure ratio for turbines. Sketch the schematic diagram and show the process on a T-s diagram Calculate the following: (ii) (!!!) Equivalence ratio The plant specific work in kJ/kg. (iv) (V) (vi) (vii) The actual thermal efficiency. Quantify the benefits of reheating in terms of a) specific work and b) efficiency. Imagine you need to increase the thermal efficiency of the turbine reheat cycle. Suggest a way this might be achieved and then design a new cycle (showing schematic and T-S diagram) and evaluate its performance (thermal efficiency). Also state its new equivalence ratio for a fixed turbine inlet temperature of 1800K. Discuss how the performance of the cycle proposed in part (vi) modifies with changes in turbine inlet temperature. Please state all assumptions, and state the limitation of this new cycle. Note: If required, assume a heat exchanger effectiveness of 0.8 for parts (vi) and (vii). A gas turbine power plant burns ethane gas in excess air, producing 250 MW of output power. It employs a single- shaft gas turbine reheat cycle and is characterised by the following data: (i) Compressor pressure ratio = 30 Ambient conditions = 1 bar & 300 K Isentropic efficiency of compressor = 0.9 Isentropic efficiencies of turbines = 0.9 each Inlet temperature of both turbines = 1800 K Pressure loss in both combustors pressure 3% of entry Turbine exhaust pressure for second turbine = 1.0 bar Combustion efficiency of both combustors = 0.96 Lower calorific value of fuel = 42 MJ/kg Take Cp of air to be 1.005 kJ.kg-1K-1 & Cp of the products to be 1.16 kJ.kg-1K-1. You can assume the combustion is isobaric and optimal pressure ratio for turbines. Sketch the schematic diagram and show the process on a T-s diagram Calculate the following: (ii) (!!!) Equivalence ratio The plant specific work in kJ/kg. (iv) (V) (vi) (vii) The actual thermal efficiency. Quantify the benefits of reheating in terms of a) specific work and b) efficiency. Imagine you need to increase the thermal efficiency of the turbine reheat cycle. Suggest a way this might be achieved and then design a new cycle (showing schematic and T-S diagram) and evaluate its performance (thermal efficiency). Also state its new equivalence ratio for a fixed turbine inlet temperature of 1800K. Discuss how the performance of the cycle proposed in part (vi) modifies with changes in turbine inlet temperature. Please state all assumptions, and state the limitation of this new cycle. Note: If required, assume a heat exchanger effectiveness of 0.8 for parts (vi) and (vii).