基于阵列稀疏分解的裂纹的定量评估羊羔波传播
Dingcheng Ji1, Fei Gao2, Jiadong Hua3
1School of Reliability and Systems Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing, China.
Ultrasonics
|July 17, 2023
概括
这项研究引入了一种使用Lamb波来检测结构中裂位置和大小的新方法. 该方法分析波反射和衍射,以准确可视化裂尺寸和方向,而无需基线数据.
科学领域:
- 结构健康监测 结构健康监测
- 非破坏性测试是指非破坏性测试.
- 波浪力学 波浪力学
背景情况:
- 工程结构的裂纹损伤可能导致灾难性的故障,特别是在应力度点.
- 羔羊波对结构缺陷敏感,为损坏检测提供了潜在的方法.
研究的目的:
- 开发一种新的方法来识别裂位置和大小,使用Lamb波反射和衍射.
- 分析Lamb波和裂之间的相互作用机制,以提取损坏信息.
- 在不依赖基线信号的情况下可视化裂大小和方向.
主要方法:
- 对与裂相互作用的Lamb波反射和衍射的分析.
- 用值将波信号分为反射和衍射进行分类.
- 为波形分析构建一个过于完整的字典.
- 稀疏分解的应用用于将信号映射到传播距离.
- 使用衍射来识别裂纹尖端,使用反射来获取边缘点信息.
主要成果:
- 该方法成功地将接收到的信号映射到没有基线数据的传播距离.
- 裂纹尖端点是使用衍射确定,边缘点是使用反射确定.
- 扭曲裂的大小和方向是使用时间域信号可视化.
- 数字模拟和实验数据显示,与实际裂纹特征的高度一致.
结论:
- 拟议的方法通过分析Lamb波相互作用,有效地识别裂位置和大小.
- 该技术在可视化裂几何学方面表现出高精度和有效性.
- 这种方法为结构完整性评估提供了一个有前途的非破坏性评估工具.
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