几乎完美传输的拉梅模式在一个矩形梁与部分和透度厚度的垂直裂
Xuwei Cao1, Jing Ni1, Chun Shao1
1School of Mechanical Engineering, Hangzhou Dianzi University, Hangzhou 310018, China.
Materials (Basel, Switzerland)
|June 10, 2023
概括
这项研究调查了裂如何影响矩形波导中的引导波传播. 研究人员发现了一种特定的频率,用于几乎完美的传输,该频率对裂深度和宽度敏感,有助于评估裂大小.
科学领域:
- 固体力学 固体力学是什么
- 波浪传播 波浪传播
- 非破坏性测试是指非破坏性测试.
背景情况:
- 波导中的引导波由于各种振动模式而表现出复杂的传播和散射.
- 了解结构缺陷 (如裂) 的模式转换对于材料完整性评估至关重要.
研究的目的:
- 分析最低的拉梅模式在矩形波导中的部分穿透或穿透厚度裂中的模式转换.
- 确定近乎完美的传输频率及其与裂纹特征的关系.
主要方法:
- 应用Floquet周期性边界条件来导出矩形光束的分散曲线.
- 进行频域分析,研究波浪相互作用与位于第一个拉梅频率附近的垂直或倾斜裂.
- 提取了位移和应力波场,以评估几乎完美的传输频率.
主要成果:
- 几乎完美的传输频率与第一个Lame频率相关,随着裂深度而增加,随着裂宽度而减少.
- 裂深度显著影响频率变化,而不是裂宽度.
- 梁厚对垂直裂的频率的影响微不足道;倾斜的裂没有这种现象.
结论:
- 对于矩形波导中的垂直裂,存在一种特定的频率,以实现近乎完美的传输,这取决于裂几何.
- 这种现象为结构健康监测中裂大小的定量评估提供了潜力.
- 对倾斜裂和其他波导体几何形状需要进一步研究.
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