通过设计激发波形和弹性元材料来聚焦宽带Lamb波的能量
Daiyao Du1, Jiadong Hua2, Chun Cui1
1School of Reliability and Systems Engineering, Beihang University, Xueyuan Road No. 37, Haidian District, Beijing, China.
Ultrasonics
|March 13, 2024
概括
这项研究引入了一种新的结构健康监测 (SHM) 方法,使用宽带Lamb波和弹性元材料来改善损伤定位. 该方法同时设计激发波形和超材料,以提高能量聚焦.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 声学 声学 在声学方面
背景情况:
- 基于LAMB波的损伤定位对于结构健康监测 (SHM) 至关重要.
- 能量聚焦增强了Lamb波损伤检测分辨率和信号对噪声比 (SNR).
- 目前用于能量聚焦的弹性超材料设计仅限于窄带波.
研究的目的:
- 提出一种使用宽带Lamb波的新能源聚焦方法.
- 同时设计激发波形和弹性元材料,以改善损伤定位.
- 为了克服目前的SHM技术中只关注窄带的局限性.
主要方法:
- 利用COMSOL有限元软件来确定超材料结构和激发波之间的关系.
- 根据计算的关系设计了一种超材料结构和激发信号形式.
- 采用3D打印 (PA2200尼龙) 来制造超材料,并在板上实验验证其性能.
主要成果:
- 证明了用于宽带Lamb波的有效能量聚焦方法.
- 与传统的窄带方法相比,实现了增强的损害定位能力.
- 通过实验测试验证了拟议的同时设计方法.
结论:
- 激发波形和弹性元材料的同时设计使宽带Lamb波的有效能量聚焦成为可能.
- 这种方法显著改善了结构健康监测中的损害定位.
- 实验验证证证实了开发的技术的实际适用性.
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