Nonlinear Analysis of Rotating Stall

Abstract

A new stall model to describe rotating stall in axial-flow compressors is established, where blade rows are replaced by semiactuator disks, flow fluctuations are permitted to be finite and nonsteady, and blade row characteristics are taken into consideration in nonlinear and nonsteady forms. Through numerical analysis using the finite difference method, it is attempted to make clear the aspects of rotating stall—such as number of stall cells, stall propagation velocity, wave shape and magnitude of disturbance and their variations with flow rate through the compressor, and the mechanisms which control them. Most of the aims are achieved by taking into consideration the effects of blade row interference and the nonlinearities of blade row characteristics.