Prediction of Small Rotating Stall in Axial Compressors Using Actuator Disc Theory

Abstract

A theoretical study of the development of rotating stall in axial compressors is presented. A small perturbation analysis is used for this purpose. The compressor is considered as a series of vaneless spaces and blade rows. The axisymmetric mean flow is of the free vortex type and blade rows are represented as actuator discs. The perturbations are three dimensional and steady with respect to a rotating reference frame. For high hub-tip ratio annuli the transfer relations for the perturbations are expressed in a matrix form. This formulation allows the prediction of the occurrence and development of rotating stall in single or multiple blade row configurations. The results of the prediction compare favourably with experimental data.