The effect of aero-engine connection interface morphologies on acoustic emission signals

There are numerous connection interface structures between various components of an aero-engine. The fault acoustic emission (AE) signals collected by sensors are inevitably transmitted through the connection interface. The connection interface with different morphologies will inevitably have different effects on the propagation of the AE signal. This results in the difference between the received signal and the source signal. Therefore, it is necessary to study the effect of connection interface structures on the propagation of fault AE signal. Firstly, this paper conducted experimental research on connection interfaces with different morphological features. The concepts of relative contact area and relative height were proposed. Secondly, the effect of relative contact area and relative height on the propagation of AE signals was studied through waveform analysis and time-frequency analysis methods. Finally, the effect of different morphological features on the attenuation and diffraction of AE signals are summarized. The research has shown that the effect of relative contact area on AE signals is greater than that of relative height. The smaller the relative contact area, the more obvious the diffraction phenomenon. This paper elucidates the propagation characteristics of AE signals in the connection interface and reveals the effect of morphological features. It provides guidance and reference for AE fault diagnosis.