Numerical Investigation of Diffuser Curvilinear Meridional Shape on Centrifugal Compressor Stage Performance

Centrifugal compressors are widely used in a variety of applications due to their advantages. Centrifugal compressors have a larger frontal area for a given mass flow rate compared with axial compressors, which limits their application in aircraft propulsion systems. Centrifugal compressors for aircraft/rotorcraft applications are commonly made up of a radial impeller with a radial vaned diffuser and a radial-to-axial bend with an exit guide vane. The main requirements for a centrifugal compressor are high efficiency, surge margin and dimensional limitations. This is a study of a diffuser design concept with curvilinear meridional shape aiming to reduce the overall radial dimensions of the centrifugal compressor stage without any sacrifice of compressor performance.