在一个等边三角形镜条的剪切波模式
1Department of Electrical Engineering, Jordan University of Science and Technology, Irbid 22110, Jordan.
The Journal of the Acoustical Society of America
|August 15, 2023
概括
这项研究分析了在等边三角形固体条中剪波传播,识别了水平偏振 (SH) 和垂直偏振 (SV) 剪波. 分析和数值方法证实了这些弹性波的切断波数和模式形状.
科学领域:
- 固体机械学 固体机械学
- 声学 声学 在声学上
- 波浪的传播方式
背景情况:
- 了解非圆形几何体中的波传播对于材料的表征至关重要.
- 以前的研究已经在简单的几何学中探索了波浪现象,但像三角形这样的复杂截面需要详细分析.
研究的目的:
- 调查平面偏振 (SH) 和垂直偏振 (SV) 剪切波在等边三角形实体条中的存在和特征.
- 为了确定切断波数,并分析这些剪切波的模式形状.
- 用数值模拟和实验数据验证分析解决方案.
主要方法:
- 基于Lamé SH波理论的分析解决方案和对称SV波的对称组件分析.
- 使用COMSOL计算分散曲线和切断波数的数值模拟.
- 使用激光振动计测量正常移位模式形状的实验验证.
主要成果:
- 识别了SH波模式作为拉梅解决方案,来自平面波叠加和反射.
- 对于诺伊曼SH模式 (4mπ/(3a)) 和第一个迪里克莱特SH模式 (4π7/(3a)) 的确定切断波数.
- 与子三角形相关的SV模式,在第一和第二个诺曼SH模式之间具有切断波数.
- 通过COMSOL模拟和实验测量证实了分析预测.
结论:
- 这项研究成功地阐明了SH和SV剪切波在等边三角条中的行为.
- 分析模型为波特征提供准确的预测,通过数值和实验数据验证.
- 这项研究有助于理解复杂的固体几何体中的波动力学.
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