基于电磁超声的金属板测厚技术仿真研究

Simulation research on metal thickness measurement based on electromagnetic ultrasonic

针对金属板厚度测量问题,研究了电磁超声波在金属板中的传播特性,根据有限元理论,利用ANSYS有限元分析软件对金属板测厚换能器进行了仿真分析。建立了测厚换能器的三维模型,对模型进行了电磁分析和电磁结构耦合分析。分别得出了被测试件内感生出的涡流和受到的洛伦兹力以及被测试件内部受到的位移情况。仿真结果表明,被测试件内质点受到的洛伦兹力方向为向下,且线圈正下方的洛伦兹力最大;通过不同时刻质点位移的变化可以直观地观察出电磁超声波在板中的传播状况;通过对单个质点位移的分析得出了该模型产生的电磁超声波的质点位移最大方向是向下的;该模型产生的超声波是向下的,可用于模拟电磁超声的测厚情况。

To discuss the issues of metal thickness measurement, the paper study the propagation characteristics of electromagnetic ultrasonic wave in the metal plate. The simulation on thickness measurement model of electromagnetic acoustic is established using finite element software ANSYS, based on the finite element theory. The model is a three--dimensional one, and the electromagnetic analysis and the structure analysis are done by ANSYS. The Lorentz force and eddy currents and displacement of specimen suffered can be obtained from the analysis. The simulation analysis shows that the direction of Lorentz force is downward and the maximum Lorentz force is below the coil. With the variation of particle displacement at different times, the electromagnetic ultrasonic wave can be observed visually. Through simulation analysis of a single particle displacement, it can be concluded that the direction of particle displacement is also downward. So, the direction of electromagnetic ultrasonic wave is downward and the model can be used to simulate the thickness measurement.