横观各向同性复合材料激光超声检测的数值模拟  

Numerical simulation of laser ultrasonic testing transversely isotropic composites

作　　者：郭珊珊 陈友兴[1] 吴其洲[1] 赵霞[1] 连亚容 GUO Shanshan;CHEN Youxing;WU Qizhou;ZHAO Xia;LIAN Yarong(School of Information and Communication Engineering,North Univensity of China,Taiyuan,Shanxi 030051,China)

机构地区：[1]中北大学信息与通信工程学院,山西太原030051

出　　处：《光电子．激光》2022年第4期443-448,共6页Journal of Optoelectronics·Laser

基　　金：山西省研究生创新项目(2020BY097);中北大学研究生科技立项项目(20201730)资助项目。

摘　　要：为了分析横观各向同性复合材料的内部材料属性,结合激光超声理论,使用仿真软件Comsol Multiphysics建立了复合材料在激光热弹下激发出超声波的等效模型,通过设置完美匹配层、低反射边界等方法消除了边界回波。采用有限元法模拟了横观各向同性材料中激发超声波的物理过程,对缺陷回波信号进行了时域分析。结果表明:平板厚度的增加会使超声波逐渐转变为高阶模态,且随着平板厚度的增加,模态的截止频率会逐渐降低,同时在横观各向同性复合材料中传播的超声波将逐渐失去Lamb波的特征,转而表现出表面波特征,将Lamb波向表面波转化激发出Rayleigh波。本次模拟为进一步研究复杂介质中超声波的产生和缺陷定位奠定了基础。In order to analyze the internal material properties of the isotropic composite material, combined with the theory of laser ultrasound, the simulation software Comsol Multiphysics is used to establish an equivalent model of the transversely isotropic materials excited by the laser thermoelastic ultrasonic wave, by setting a perfect matching layer, low reflection boundary, etc.The method eliminates the boundary echo.The finite element method is used to simulate the physical process of ultrasonic excitation in transversely isotropic materials, and the time-domain analysis of the defect echo signal was carried out.The results show that the increase in the thickness of the plate will gradually transform the ultrasonic wave into a higher-order mode, and as the thickness of the plate increases, the cut-off frequency of the mode will gradually decrease, and the ultrasonic wave propagating in the isotropic composite material will gradually lose the Lamb wave.In turn, it shows the characteristics of surface waves, transforming Lamb waves into surface waves and excites Rayleigh waves.This simulation lays a foundation for further research on the generation of ultrasonic waves and defect location in complex media.

关 键 词：激光超声检测 横观各向同性材料 缺陷检测 数值模拟 

分 类 号：TN249[电子电信—物理电子学]