基于分形声学超材料的宽带声聚焦透镜
发布时间：2018-08-20 13:29
【摘要】：声学超材料,是一种用于操纵声波的人工声学结构,具有诸多自然界所不具备的超常物理性质.不同于早期的局域共振声学单元结构,基于希尔伯特分形曲线提出了一种具有低损耗、高折射率的分形声学超材料,给出了分形结构声学单元的进化过程,并运用等效媒质理论,提取了具有亚波长的分形超材料单元的相对折射率、相对阻抗、等效密度及等效模量等材料参数.由于分形结构具有的自相似性和空间折叠特性,所提出的分形超材料具有宽带工作频率响应,为众多应用场合比如声超分辨率成像及声隧穿效应器件提供了候选材料.为检验分形声学超材料特性,应用分形声学超材料设计了梯度折射率分布的声聚焦透镜,并由固体方块阵列仿真对比、实验测量、以及点声源入射等三种手段验证了分形声学超材料参数特性及其聚焦透镜在2~5kHz宽频带内良好的聚焦能力.
[Abstract]:Acoustic metamaterial is an artificial acoustic structure used to manipulate sound waves, which has many unusual physical properties that nature does not possess. Unlike the early local resonance acoustic unit structure, a fractal acoustic metamaterial with low loss and high refractive index is proposed based on Hilbert fractal curve, and a fractal structure acoustic monolayer is given. The relative refractive index, relative impedance, equivalent density and equivalent modulus of the fractal metamaterials with sub-wavelength are extracted by using the theory of equivalent medium. In order to test the properties of fractal acoustic metamaterials, the acoustic focusing lens with gradient refractive index distribution is designed by using fractal acoustic metamaterials. The fractal is verified by solid block array simulation, experimental measurement and point source incidence. Acoustic characteristics of metamaterial and its focusing ability of focusing lens in 2~5kHz broadband.
【作者单位】： 东南大学毫米波国家重点实验室;北方信息控制集团有限公司;
【基金】：国家自然科学基金(61571117;61138001;61171024;61171026)
【分类号】：TB51
[Abstract]:Acoustic metamaterial is an artificial acoustic structure used to manipulate sound waves, which has many unusual physical properties that nature does not possess. Unlike the early local resonance acoustic unit structure, a fractal acoustic metamaterial with low loss and high refractive index is proposed based on Hilbert fractal curve, and a fractal structure acoustic monolayer is given. The relative refractive index, relative impedance, equivalent density and equivalent modulus of the fractal metamaterials with sub-wavelength are extracted by using the theory of equivalent medium. In order to test the properties of fractal acoustic metamaterials, the acoustic focusing lens with gradient refractive index distribution is designed by using fractal acoustic metamaterials. The fractal is verified by solid block array simulation, experimental measurement and point source incidence. Acoustic characteristics of metamaterial and its focusing ability of focusing lens in 2~5kHz broadband.
【作者单位】： 东南大学毫米波国家重点实验室;北方信息控制集团有限公司;
【基金】：国家自然科学基金(61571117;61138001;61171024;61171026)
【分类号】：TB51
【相似文献】
相关期刊论文 前10条
1 王总;朱文君;唐玲;;超材料技术发展概览[J];军民两用技术与产品;2012年07期
2 弓巧侠;刘晓e，
本文编号：2193786
本文链接：https://www.wllwen.com/guanlilunwen/gongchengguanli/2193786.html
