Correct Answer - Option 1 :
9 bar
Concept:
In multistage compression with inter cooling complete (or) Inter cooling is perfect i.e., air is cooled at constant pressure to its initial pressure.
The intermediate pressures are given by the stage pressure ratio as
\(r = {\left( {\frac{{{p_f}}}{{{p_o}}}} \right)^{\frac{1}{n}}}\)
Where n – number of stages, pf – delivery pressure, po – suction pressure;
In two stage compression, the intermediate pressure is given by
\({p_i} = \sqrt {{p_f}{p_o}} \)
Calculation:
Given po = 1.013 bar, pf = 80 bar;
Now
\({p_i} = \sqrt {1.013 \times 80} = 9\;bar\)
