分析和数值建模非线性羔羊波与低频调节的呼吸裂的相互作用
Peilong Yuan1, Xiaodong Xu2, Christ Glorieux3
1Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics, Department of Physics, Nanjing University, Nanjing 210093, China; Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D, B3001 Leuven Belgium.
Ultrasonics
|April 5, 2024
概括
这项研究使用Lamb波和接触声学非线性 (CAN) 来研究板块中的呼吸裂. 结果显示,在结构健康监测 (SHM) 中评估疲劳裂严重性的调制机制至关重要.
科学领域:
- 固体力学 固体力学是什么
- 非破坏性测试 不破坏性测试
- 声学非线性 声学非线性
背景情况:
- 材料中的疲劳裂可以改变结构完整性.
- 羊羔波对微小尺度的缺陷非常敏感.
- 接触声学非线性 (CAN) 为缺陷特征提供了一种方法.
研究的目的:
- 为了分析通过呼吸裂的Lamb波传播.
- 为了研究通过呼吸裂产生的接触声学非线性 (CAN).
- 为结构健康监测 (SHM) 建立CAN和裂纹特征之间的定量相关性.
主要方法:
- 分析计算和有限元 (FE) 模拟Lamb波传播.
- 模式分解,里埃转换和基于变量原理的算法.
- 对接触面边界条件和低频调制对裂行为的影响的分析.
主要成果:
- 计算了基本和第二波频率的反射和传输系数.
- 量化CAN与微裂宽度相关,通过变化的事件波幅与裂宽度比.
- 证明了CAN和裂关闭的低频调制之间的定量相关性.
结论:
- 分析和FE结果显示出良好的一致性.
- 了解CAN调制对于准确的疲劳裂严重性评估至关重要.
- 这种方法在SHM系统中的微疲劳裂的定量评估中具有重要的应用.
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