isothermal compression

adiabatic compression

isentropic compression

polytropic compression

no flow of air

fixed mass flow rate regardless of pressure ratio

reducing mass flow rate with increase in pressure ratio

increased inclination of chord with air steam

1:1.2

1:2

1:5

1:10

6 kg/cm2

10 kg/cm2

16 kg/cm2

25 kg/cm2

air stream blocking the passage

motion of air at sonic velocity

unsteady, periodic and reversed flow

air stream not able to follow the blade contour