基于模拟机匣的中介轴承微弱故障特征提取技术

Weak Fault Feature Extraction Technology of Intermediate Bearing Based on Analog Casing

中介轴承是航空发动机支承传动系统中的重要零件,其运行状态直接影响航空发动机的工作状态和运行安全。围绕航空发动机中介轴承微弱故障特征信号提取的问题,以振动信号分析和处理为基础,开展航空发动机中介轴承微弱故障特征信号提取实验。仿照某型涡扇发动机机匣结构设计加工了模拟机匣,用来模拟振动信号的复杂传递路径。基于包络谱分析和经验模态分解(empirical mode decomposition,EMD)包络谱分析处理振动信号,对比二者对滚动轴承微弱故障特征信号的提取效果。实验结果表明,在中介轴承微弱故障特征信号提取中,模拟机匣可以有效地模拟振动信号的复杂传递路径,EMD包络谱分析法比单一采用包络谱分析的方法能够更加明显有效地提取中介轴承微弱故障信号。

Intermediate bearing is an important part of aero-engine supporting transmission system,and its running state directly affects the working state and operation safety of aero-engine.On the basis of vibration signal analysis and processing,aero-engine intermediate bearing weak fault feature signal extraction experiment was carried out.An analog casing was designed and processed to simulate the complex transmission path of vibration signal.Based on envelope spectrum analysis and empirical mode decomposition(EMD)envelope spectrum analysis,the vibration signal was processed,and the extraction effect of the weak fault characteristic signal of rolling bearing was compared.Experimental results show that in the extraction of weak fault characteristic signal of intermediate bearing,the analog casing can effectively simulate the complex transmission path of vibration signal,the EMD envelope spectrum analysis method can extract the weak fault signal of intermediate bearing more obviously and effectively than the single method using envelope spectrum analysis.