转静轴向间距对压气机静子叶片气流激励的影响

Influence of rotor-stator axial spacing on compressor stator blade aerodynamic excitation

为考查转静轴向间距对跨声速压气机静子叶片气流激励的影响,采用非定常数值方法模拟了3.5级跨声速压气机的三维非定常流场。通过叶片表面非定常压力频域分析,建立了静子叶片气流激励源与上、下游叶片通过频率的关系,分析了不同转静轴向间距下静子叶片表面气流激励的变化规律。结果表明:静子叶片表面非定常气流激励频率为上、下游转子叶片的通过频率及其倍频,且主导激励源为下游转子;随着转静轴向间距增加,下游转子对上游静子的气流激励强度明显减弱。存在一个最佳转静轴向间距,既能保证压气机级效率处于较高水平,同时又能使压气机静子叶片气流激励相对较小。

In order to investigate the effects of rotor-stator axial spacing on aerodynamic excitation of tran⁃sonic compressor stator blade,an unsteady numerical simulation method was applied to study the three-di⁃mensional unsteady flow of 3.5-stage transonic compressor.The excitation source was identified as the up⁃stream and downstream blade passing frequency by analysis of unsteady pressure.The change laws of aero⁃dynamic excitation had been conducted on different rotor-stator axial spacing.The results show that the fre⁃quency of unsteady pressure fluctuation on stator blade is the passing frequency and its multiplier of up⁃stream and downstream rotor,and the main excitation source is the downstream rotors.With the increase of the axial spacing,the aerodynamic excitation intensity of upstream stator would be significantly weakened.There is an optimal rotor-stator axial spacing,which not only satisfies the compressor stage efficiency at a high level,but also makes the compressor stator blade aerodynamic excitation smaller.