声学元面具有弗里兹对称性)
D B Moore1, T A Starkey1, G J Chaplain1
1Centre for Metamaterial Research and Innovation, Department of Physics and Astronomy, University of Exeter, Exeter EX4 4QL, United Kingdom.
The Journal of the Acoustical Society of America
|January 23, 2024
概括
这项研究设计了基于Frieze组的声学元表面,使用对称性破坏来控制声波特性. 这项研究展示了一种新的方法,通过工程对称度来定制声学分散.
科学领域:
- 声学 声学 在声学方面
- 材料科学 材料科学 材料科学
- 固态物理 固态物理
背景情况:
- 弗里兹图案描述了无限条带的规则 (反射,旋转,转换).
- 超材料利用潜在的对称性及其战略性破坏来定制波散.
- 了解这些对称性是设计高级功能材料的关键.
研究的目的:
- 设计,模拟和实验性地描述一维声学元表面.
- 探索Frieze组在声学元材料设计中的应用.
- 为了证明工程对称性如何影响声学特性.
主要方法:
- 利用Frieze组来定义元表面的单元细胞结构.
- 采用计算模拟来预测声学行为.
- 进行了制造后表面的实验性表征.
主要成果:
- 成功设计和制造了七个不同的一维声学超表面.
- 每个超表面的单位单元对应于一个独特的Frieze组.
- 通过对称性操纵来定制声学分散的能力.
结论:
- 结组为设计声学元表面提供了一个强大的框架.
- 在这些结构中,战略性地打破对称性,可以精确控制声波传播.
- 这项工作为开发可调节的声学设备开辟了新的途径.
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