航空发动机压气机静子通道压力信号时频特征

进行发动机整机试验,获取了压气机第一级静子通道内的压力信号.通过时频分析,从压力信号中辨识出了以550 Hz和2200 Hz为中心的时频结构;辨识出了压气机前3级转子叶片通过频率信号及它们的一些和频、差频信号.同时,还观察到在试验发动机减速过程中,放气带打开前,压气机前3级转子的叶片通过频率信号及它们的一些和频、差频信号幅度显著增强,这表明减速过程中压气机第一级转子尖区的流动分离逐渐趋于严重.因此,监控压气机静子通道压力信号时频特征的变化,可以获得特定的压气机转子的流场信息,从而为压气机稳定性控制提供重要依据. 

Time-frequency characteristics of stator passage pressure signal of aeroengine compressor

Tests on aeroengine were conducted to obtain stator passage pressure signal of the first compressor stage of a test aeroengine.By means of time-frequency analysis,the time-frequency structures centered on 550 Hz and 2 200 Hz were identified;the blade passing frequency of the first 3 compressor rotors,and some of their sum-frequency and difference frequency signals,were identified too.It's also observed that for the first 3 compressor rotors,in the process of engine throttling,the blade passing frequencies,their sum-frequency and difference frequency signals would gradually increase their magnitudes before the opening of discharge valve,which indicated that the first compressor tip region flow separation became server following the decrease of engine speed.Thus compressor rotor flow field information might be obtained through monitoring the time-frequency characteristics of pressure signal of specific compressor stator passage,which was helpful for the control of compressor stability.