压气机转子叶片所受激励的相关性

Study on the correlative property of excitation on compressor rotor blades

为了分析复杂流场对叶片的作用,研究了压气机内三种非定常气动激振形式:上游叶片排尾迹、进气畸变和旋转失速的相关性.通过在单级低速轴流压气机试验台上获得的数据,采用自相关和互相关方法,研究三种激励的特性,分析激振信号的相关性机理.结果表明:多次自相关可以清晰地显示出信号的特征频率,有效地抑制干扰噪声;激励信号之间具有很强的相关性,且相关程度主要由偶数阶激励信号产生;两两激励信号之间的互相关频率成分幅值较低,低于各信号的自谱图在该处的幅值;而三个激励信号之间的相关程度较低,其相关性主要存在于偶数阶激励信号的前两阶.

The correlation of the three excitation forms （up-stream blade rows wakes, inlet distortion and rotating stall） was studied to analyze complex flow field of the blade role. The experimental samples were obtained by a single-stage low speed axial compressor test rig. Research focused on analysis of these three types of periodical excitation, employed autocorrelation and cross-correlation approach. Experimental results show that there is high correlation between excitation signals, and the correlation degree rely heavily on even signal. In addition, there is lower amplitude of cross-correlation frequency than amplitude of autocorrelation signal; There is low magnitude correlation among three excitations, correlation mainly exist in the first two of the even degree signal.