"积累效应"的第二和羔羊波在一个损失的板块
Shengbo Shan1, Yuanman Zhang2, Liaoliao Cheng1
1School of Aerospace Engineering and Applied Mechanics, Tongji University, Shanghai 200092, People's Republic of China.
Ultrasonics
|December 19, 2023
概括
二次波Lamb波对材料缺陷具有很高的敏感性. 本研究提出了一种方法,用于预测它们在受湿结构中的累积特征,确定一个最佳的区域来检测损坏.
科学领域:
- 非线性超声波是一种非线性超声波.
- 材料科学是一种材料科学.
- 结构性健康监测 结构性健康监测
背景情况:
- 二次波Lamb波对微观结构缺陷敏感,对于监测薄壁结构至关重要.
- 这些波的累积性质对于非线性波测量是有益的,但受到损失结构中减缓的影响.
研究的目的:
- 提出一种新的方法来预测沉板中的第二波Lamb波的累积特征.
- 为了应对影响波积累的能量消散的挑战,由于物质的阻尼.
主要方法:
- 开发了一种基于Lamb波的基本和双频衰减模式的预测方法.
- 将波束分歧的影响纳入预测模型.
- 通过有限元模拟和实验测试验证了方法.
主要成果:
- 沉板中的累积的第二波Lamb波在振幅上呈现出一个增加,随后是幅度的减少.
- 一个具有相对较大的振幅的"甜蜜"区域被确定并使用拟议的方法可预测.
- 该研究量化了阻尼和波束分歧对波浪积累的影响.
结论:
- 拟议的方法有效地预测了沉结构中第二波Lamb波的累积特征.
- 了解这些累积性质对于设计有效的结构损坏检测和监测系统至关重要.
- 这项研究为优化现实应用中的非线性超声波技术提供了实际指导.
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