基于使用定期永久磁铁的电磁声传感器进行反对称羔羊波模拟研究
Lianren Du1, Ruizhen Gao1, Xiaojuan Jia1
1College of Mechanical and Equipment Engineering, Hebei University of Engineering, Handan 056038, China.
Sensors (Basel, Switzerland)
|August 26, 2023
概括
一种新型的水平偏振周期常磁电磁声传感器 (HP-PPM-EMAT) 增强了A0模式的Lamb波,并抑制了S0模式. 这项创新显著提高了A0模式Lamb波的纯度,用于非破坏性测试应用.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 声学 声学 在声学方面
背景情况:
- 羔羊波对于非破坏性测试至关重要,但受到多模式干扰的影响,限制了信号处理.
- 传统的电磁声学传感器 (EMAT) 难以分离特定的Lamb波模式,阻碍了准确的分析.
- 开发专门的传感器对于克服Lamb波散射和干扰问题至关重要.
研究的目的:
- 提出和评估一个水平偏振周期永久磁铁电磁声学传感器 (HP-PPM-EMAT),以提高Lamb波模式的选择性.
- 在信号特性方面,将HP-PPM-EMAT与传统EMAT的性能进行比较.
- 为了优化HP-PPM-EMAT设计,最大限度地提高A0模式Lamb波幅比S0模式.
主要方法:
- 开发一个二维有限元模型来模拟磁流密度,洛伦茨力和信号强度.
- 使用有限元素模型对传统的EMAT和拟议的HP-PPM-EMAT进行比较分析.
- 应用直角测试理论来研究结构参数对A0/S0模式幅度比的影响.
- 在HP-PPM-EMAT中基于直角测试结果优化磁铁单位宽度.
主要成果:
- 惠普-PPM-EMAT有效地增强了A0模式的Lamb波 (A0波),同时抑制了S0模式的Lamb波 (S0波).
- 模拟结果表明,两种传感器类型之间的磁流密度和洛伦茨力分布存在显著差异.
- 对HP-PPM-EMAT设计的优化导致A0到S0总位移幅度比提高了7.74倍.
结论:
- 惠普-PPM-EMAT是一种有前途的技术,用于生成更高纯度的A0模式Lamb波.
- 这一进步解决了非破坏性测试中多模式Lamb波引起的信号处理干扰.
- 优化的HP-PPM-EMAT设计在模式选择性上提供了显著的改进,提高了基于Lamb波的检查技术的可靠性.
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