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Question 11.5: Calculate the thermal efficiency and work ratio of the plant...

Calculate the thermal efficiency and work ratio of the plant is example 25.4, assuming that c_{p} for the combustion process is 1.11 kJ/kg K.

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Heat supplied= c_{p}     (T_{3}    –    T_{2}′)
= 1.11 (883 – 529) = 392.9 kJ/kg

η_{thermal}   =   \frac{Network   output}{Heat   supplied}     =   \frac{48.2}{392.9} =  0.1226   or    12.26%.

Now,                         Work ratio =  \frac{Network   output}{Gross     work    output}     =   \frac{48.2}{W_{turbine}}   =  \frac{48.2}{290.4}    =  0.166.

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