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Q2. In the gas turbine plant shown in Fig Q2, the High Pressure Turbine drives the compressor and the Low Pressure Turbine driving the load. There is reheat between the stages.

At a particular operating condition:

The High Pressure Turbine pressure ratio is 4.748 :1

The overall pressure ratio is 9 : 1

The air enters the compressor at a temperature of 15℃.

The hot gas leaves the Combustion Chamber at 950 K and the Reheated at 850 K.

The isentropic efficiency of the compressor is 85 % and that of the Low Pressure turbine is 88 %. The mass flow of fuel and system losses may be ignored.

(a) Calculate EACH of the following:

(i) The specific work output; (4)

(ii) The High Pressure Turbine outlet temperature; (4)

(iii) The thermal efficiency. (4)

(b) Sketch the cycle on a Temperature-specific entropy diagram showing the temperatures. (4)

Note: for air γ = 1.4, C_P = 1.005  kJ⁄(kg K)

for gas γ = 1.33 ; C_P = 1.11  kJ⁄(kg K)