基于声信号的航空发动机风扇叶盘共振特征识别

Identification of aero-engine fan blade disk resonance characteristics based on acoustic signal

航空发动机风扇叶盘模态密集,激励源丰富,使得风扇叶片容易共振出现裂纹、掉块等故障。针对振动应力、叶尖振幅和传声器阵列等测试方法复杂、成本高、周期长等特点,在风扇进气管道口布置单个传声器测量进口声信号,并对声信号进行时频分析,能够清晰识别出风扇叶盘的同步、非同步共振特征,结合计算结果分析获得共振转速和固有频率,与叶尖振幅测量结果相比最大误差分别为0.22%和0.42%,验证了该结果的准确性,为航空发动机风扇叶片盘设计和故障诊断提供了简单、有效的监测手段。

Aero-engine fan blade disk has dense modes and abundant excitation sources,which makes the fan blade prone to cracks,falling blocks and other failures.The complex methods,such as vibration stress,tip amplitude and microphone array,are costly and time-consuming.The single microphone is arranged at the fan in-let pipe to measure the inlet acoustic signal.The time-frequency analysis of the acoustic signal can clearly identi-fy the synchronous and non-synchronous resonance characteristics of the fan blade disk.Combined with the cal-culation results,the resonant speed and natural frequency are obtained.Compared with the measured results of the blade tip amplitude,the maximum error is 0.22%and 0.42%respectively,which verifies the accuracy of the results and provides a simple and effective method for the design and fault diagnosis of the aero-engine fan blade disk.