Dispersion curve analysis method for Lamb wave mode separation
Dispersion curve analysis method for Lamb wave mode separation
复制标题
DOI：
10.1177/1475921719890590
复制
发表时间：
2019-12-05
影响因子：
6.6
通讯作者：
Li, Fucai
中科院分区：
文献类型：
--
作者：
Hu, Yue;Zhu, Yanping;Li, Fucai
兰姆波检测技术已成为一种很有前途的结构健康监测和无损检测方法。然而，由于兰姆波的高色散和多模态特性，兰姆波模式分离成为一个具有挑战性的问题。基于频散曲线分析，本文提出了一种新的信号处理方法来解决这一问题。首先，基于Hessian矩阵构造了一个新的函数，以增强时频表示中色散曲线的能量集中，从而降低色散效应。随后，约束罚函数算法被开发用于检测频散曲线。最后，提出了一种模式重构算法，用于兰姆波模式的重构。该方法通过增强兰姆波信号的时频特征，实现了对重叠波模式的分离，并对裂纹故障进行了检测。通过两个实验验证了该方法对兰姆波模式分离的有效性。
The Lamb wave inspection has emerged as a promising method for structural health monitoring and nondestructive testing. However, because of the highly dispersive and multimodal features, the Lamb wave mode separation has become a challenging problem. Based on the dispersion curve analysis, a new signal processing method is proposed in this study to solve this problem. First, a novel function based on the Hessian matrix is constructed to enhance the energy concentration of the dispersion curve in the time-frequency representation to reduce the dispersion effect. Subsequently, the constrained penalty function algorithm is developed for detecting dispersion curves. Finally, a mode reconstruction algorithm is developed to recover Lamb wave modes. The proposed method can separate overlapping wave modes and detect the crack fault by enhancing the time-frequency feature of the Lamb wave signal. Two experiments are carried out to verify the effectiveness of the proposed method for Lamb wave mode separation.