关键词: 轴流式压气机;旋转失速;小扰动波

Abstract: Small perturbation was studied in low speed axial compress experiments to find out the mechanism of the rotating stall.The experimental results show that prior to the rotating stall, a small perturbation with one cell was observed traveling around the circumference of the machine with a speed almost equal to that of fully developed rotating stall, but in the amplification process of this perturbation, the cell was broken into three blocks and rotating stall appears finally with three cells. Temporal and spatial analysis of hot wire signals indicate that the small perturbation originates from the boundary layer of casing ahead the rotor and amplification of this perturbation causes the onset of rotating stall.

Key words: Axial flow compressor;Rotating stall;Small perturbation~+