The pressure ratio per stage for a centrifugal compressor is

Concept:

Centrifugal compressor

• Air is drawn into the centre of a rotating impeller with radial blades and is pushed toward the centre by centrifugal force.
• This radial movement of air results in a pressure rise.
• The airflow rate is more than a reciprocating compressor. but the maximum pressure value is less than the reciprocating compressor.
• Centrifugal compressors were used in jet engines and smaller gas turbine engines.
• For larger engines, axial compressors need a lesser frontal area and are more efficient.

Pressure ratio for centrifugal compressor = 4 : 1

Pressure ratio for axial flow compressor = 1.2 : 1