Damage localization of aero engine blade based on Lamb wave theoretical propagation model and imaging algorithm

Abstract

Aero engine is the core component of the whole aircraft, and the blade plays a significant role in the aero engine. The working environment of the blade is often very harsh, so the probability of damage is high. Due to the variable cross-section characteristics of blade structure, traditional Lamb wave damage detection methods cannot be directly applied to blades. To locate blade damage efficiently and accurately, a detection method based on the Lamb wave theoretical propagation model of variable cross-section structure and damage localization imaging algorithm is proposed in this study. First, the propagation law of Lamb wave on the blade with variable cross-section is obtained through theoretical analysis, and the corresponding theoretical model is established. Subsequently, the damage location is identified and the image is generated by delay-and-sum algorithm and minimum variance algorithm. Finally, experiments on the blade are carried out, and the damage location is successfully identified, which verifies the validity of the proposed method in damage localization of variable cross-section aero engine blade.