组合压气机旋转失速特征的小波分析

采用高频响动态压力探针测量了小流量轴流/离心组合压气机的旋转失速和喘振,并采用基于Morlet小波时频分析和小波系数奇异分解的方法分析了压气机失速信号.研究结果表明:稳定工况下,频率分量较多、幅值较小.失速工况下,特征频率能量较大、且成倍频关系.在该组合压气机的失稳过程中,并没有引起大幅度的压力脉动.压气机光滑地从失速前出现的模态波过渡到完全失速.周向存在2个失速团,失速团传播速度约为44.8%~45.9%转速.

Wavelet analysis of features of rotating stall in a combined compressor

A fast response pressure probe was applied to test the rotating stall and surge of an axial and centrifugal combined compressor.The pressure signals were analyzed by utilizing the method of the time-frequency analysis based on the Morlet and singular value decomposition.The experimental results indicate that,at the stable condition,there are many main frequency components in the frequency domain but the amplitude is small,while,at the stall condition,the energy of the frequency components becomes larger.In the process of unstall to stall,the larger amplitude of the pressure fluctuation does not produced by the stall cell in this compressor.The compressor enters smoothly into the full stall condition from the modal wave.2 stall cells are measured around annulus and the propagation speed of the stall cell is from 44.8% to 45.9% rotor speed.