基于台架试验的涡轴发动机喘振发生位置规律

为了探究某型涡轴发动机喘振发生位置规律，采集并分析了台架喘振试验时进气道、轴流压气机叶尖、轴流压气机出口和离心压气机出口的压力信号。采用连续小波时频变换对压力信号进行特征提取，以小波系数作为喘振信号特征，阈值为小波系数最大值的10%，结果表明:某型涡轴发动机的轴流压气机总是比离心压气机先发生喘振，喘振在轴向上由进气道向离心压气机传递的同时，在周向上也沿着压气机转子叶片旋转方向传递。对某型号发动机进行实时喘振监测时，监测轴流压气机能比监测离心压气机更早发现喘振，在后续某型涡轴发动机改型设计时，可增加轴流压气机的喘振裕度来提升整机防喘能力。 

Position rule of turboshaft engine surge based on bench test

In order to investigate the surge position of turboshaft engine，the pressure signals of air inlet，axial compressor tip，axial compressor outlet and centrifugal compressor outlet were collected and analyzed during the bench surge test.Continuous wavelet time-frequency transform was used to extract the characteristics of the pressure signal.The wavelet coefficients were used as the characteristics of the surge signal，and the threshold value was 10% of the maximum value of the wavelet coefficients.The results showed that the axial flow compressor of a turboshaft engine surged earlier than the centrifugal compressor，and the surge was transmitted from the inlet to the centrifugal compressor in the axial direction，and also along the rotor blade rotation in the circumferential direction.When the real-time surge monitoring was carried out for a certain type of engine，the surge can be detected earlier by monitoring the axial compressor than by monitoring the centrifugal compressor.In the subsequent modification design of a certain type of turboshaft engine，the surge margin of the axial compressor can be increased to improve the anti-surge ability of the whole engine.