在厚壁结构中,局部可塑性诱导的非线性表面波散射.
Yuanman Zhang1, Shengbo Shan2, Li Cheng1
1Department of Mechanical Engineering, The Hong Kong Polytechnic University, Kowloon, Hong Kong; Hong Kong Branch of National Rail Transit Electrification and Automation Engineering Technology Research Center, The Hong Kong Polytechnic University, Kowloon, Hong Kong.
Ultrasonics
|June 4, 2024
概括
在厚壁结构 (TWSs) 中早期检测损坏至关重要. 这项研究表明,非线性弹性波从初始的表面损伤分散,产生可检测的剪切波用于结构健康监测.
科学领域:
- 结构工程 结构工程
- 材料科学 材料科学 材料科学
- 非线性声学 非线性声学
背景情况:
- 厚壁结构 (TWS) 是关键的承载元件,需要早期检测损坏,以确保安全.
- 非线性弹性波技术为损害评估提供了希望,但由于TWS中复杂的波传播而面临挑战.
研究的目的:
- 研究与TWS表面局部塑料损伤相互作用的非线性弹性波的散射特性.
- 了解来自初始损伤前体的非线性波的产生和传播.
主要方法:
- 利用有限元模拟来模拟波相互作用.
- 对精心制造的TWS进行了实验,这些TWS具有局部塑化损伤.
- 分析了非线性准表面波的散射特征,并产生了剪切散热波.
主要成果:
- 非线性准表面波和剪切散装波是在与非线性材料区域相互作用时产生的.
- 分散的非线性剪切波显示出强大的,可预测的定向性和高的非线性能量含量.
- 观察到剪切波向TWS的相反表面分散.
结论:
- 这项研究证明了非线性弹性波散射在检测TWSs初始表面损伤方面的潜力.
- 产生的非线性剪切波提供了一个可行的手段,由于其导向性和能量,损害定位.
- 这项研究有助于推进关键基础设施的结构健康监测技术.
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