The Effect of Rotor Blade Wakes on Centrifugal Compressor Diffuser Performance—A Comparative Experiment

Abstract

A vortex nozzle facility for testing radial vaned diffusers independently of any rotor has been developed [1, 2]. This paper describes a comparative experiment designed to evaluate the applicability of results obtained on this facility to actual rotating compressors. Geometrically scaled diffusers were tested in the vortex nozzle facility and in an actual rotating compressor rig, and the results are compared and shown to be very similar in terms of both performance and stability limits. The implications of these results are that blade wake mixing and unsteadiness do not significantly affect diffuser performance.