According to analysis of the characteristics of frequency and propagation of the sound generated by the rotating stall,an acoustic measuring method is developed,in which the characteristic parameters,such as the number and propagation speed of stall cells,are measured.Compared with existing methods,this method is a untouched measurement so as to avoid not disturb ance of the flow field .The primary experimental results obtained on a transonic axial-flow compressor facility demostrate the feasibility of this method.
