An investigation of rotating stall in a single stage axial compressor

Abstract

The rotating stall characteristics of a single stage axial flow compressor were investigated. The number of stall cells and their propagation velocities were found with and without stator blades. The measured velocities were compared with those predicted by Stenning's theory, assuming the downstream pressure fluctuations to be negligible, and correlation within 25% was obtained over a wide range of stall patterns. It was found that the pressure fluctuations caused by rotating stall were less downstream of the rotor than upstream; the minimum reduction across the rotor was 40% with stator blades, and 75% without stator blades. It was also found that, for the compressor tested, the stator blades decreased, the number of stall cells and tended to induce rotating stall at larger mass flow rates.