钢丝绳声发射信号传播特性分析

针对钢丝绳断丝缺陷的在役动态监测需要，提出采用COMSOL软件对钢丝绳的声发射检测信号传播特性进行研究。首先建立钢丝绳结构模型，然后模拟不同频率、不同位置的断丝声发射信号在结构中的传播过程，获得不同位置的信号位移场及能量变化，最后根据导波理论，采用模态特征曲线结合小波变换分析不同类型声发射源的特征频率与模态成分。结果表明:声发射信号传播过程中，对于不同频率和激发方向的声发射源，其主要模态成分和特征频率的差异较大，可根据不同位置的时频分析结果，结合理论频散曲线判别声发射源信号的主要模态特征，并确定结构中声发射源的不同振动方向与中心频率。该研究结果可为钢丝绳损伤声发射检测提供理论参考依据。

Analysis on Transmission Characteristics of Acoustic Emission Signal of Wire Rope

In order to meet the needs of in-service dynamic monitoring of broken wire defect of steel wire rope, COMSOL software was used to simulate the acoustic emission detection of steel wire rope. Firstly, the structure model of wire rope was established. Then, the transmission process of acoustic emission sources with different frequencies and positions in the structure was simulated, and the displacement field and energy change of signals with different positions were acquired. Finally, according to the guided wave theory, the characteristic frequencies and modal components of different types of acoustic emission sources were analyzed by using wavelet transform combined with the dispersion characteristics. The experimental results show that, concerning acoustic emission sources with different frequencies and excitation directions, the main modal components and eigenfrequencies are quite different while the acoustic emission signal propagates. Based on the time-frequency analysis at different locations with the theoretical dispersion curve, the main modal characteristics of the acoustic emission source signal can be identified, and the different vibration directions and center frequencies of the acoustic emission sources in the structure are determined. The research results can provide a theoretical reference for the detection of wire rope damage using acoustic emission.