基于全波形反演的SH1导波缺陷检测仿真  

Simulation of SH1 guided wave defect detection based on full waveform inversion

作　　者：温家炜 江灿 陈浩[1,2] WEN Jiawei;JIANG Can;CHEN Hao(Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院声学研究所,北京100190 [2]中国科学院大学,北京100049

出　　处：《声学技术》2025年第1期65-73,共9页Technical Acoustics

摘　　要：基于全波形反演的导波层析成像方法,与其他层析成像算法相比成像精度更高,在工业腐蚀检测中展现了巨大的应用潜力。目前基于全波形反演算法的导波检测主要选择A0、S0模式,但受限于所选激励频段、波长大小与反演厚度的灵敏度,A0、S0模式在浅表与小尺度腐蚀缺陷检测时,成像精度相对较低。文章提出了一种利用SH1模式波进行浅表与小尺寸腐蚀缺陷高精度成像的全波形反演方法。该方法首先采用有限元方法模拟了在含有不同尺寸缺陷铝板表面使用环形阵列采集的时域波形,然后采用频率域全波形反演算法对仿真数据进行处理,对比分析了激励A0、S0、SH1三种模式的导波时,全波形反演算法对不同尺寸缺陷的成像精度,最后考察了缺陷位置、复杂缺陷对成像精度的影响。成像结果表明:缺陷位于环形阵列中心区域时,SH1模式相比于A0、S0模式成像精度更高;在缺陷偏离环形阵列中心区域以及缺陷不规则的情况下,全波形反演算法依然保持较高的成像精度,验证了基于全波形反演算法的SH1导波对浅表腐蚀缺陷成像的可行性。The guided-wave tomography method based on full-waveform inversion has higher imaging accuracy compared with other tomography algorithms and shows great potential for application in industrial corrosion detection.Currently,the A0 and S0 modes are primarily used for ultrasonic guided wave testing based on fullwaveform inversion.Limited by the sensitivity of the selected excitation frequency band,wavelength size,and inversion thickness,the imaging accuracy of A0 and S0 modes is relatively low when used for shallow and small-scale corrosion defect detection.In this paper,a full-waveform inversion method is proposed for high-precision imaging of shallow and small-sized corrosion defects using SH1 mode waves.Firstly,the finite element method is used to simulate the time-domain waveforms collected from a circular array on the surface of aluminum plates containing defects of different sizes.Then,the frequency domain full-waveform inversion algorithm is used to process the simulation data.The imaging accuracy of the full-waveform inversion algorithm on defects of different sizes was compared and analyzed when exciting guided waves of A0,S0,and SH1 modes.Finally,the influence of defect location and complex defects on imaging accuracy is investigated.The imaging results reveal that the SH1 mode provided superior imaging resolution compared to the A0 and S0 modes when the defects are situated at the center of the annular array.Furthermore,the full-waveform inversion algorithm maintains high imaging resolution even when the defects are offcenter or irregularly shaped.This validates the feasibility of employing the full-waveform inversion algorithm for imaging shallow surface corrosion defects in SH1 guided waves.

关 键 词：全波形反演 SH1模式 导波层析 

分 类 号：TB559[理学—物理]