局域共振型五模超构材料的低频声波调控方法

Tuning Method of Low-Frequency Acoustics for Locally Resonant Pentamode Metamaterials

五模超构材料是一类具有固体结构与"流体"特性的人工微结构,由于较好的压缩波与剪切波的解耦合能力、较低的填充率、丰富的晶格构型及可调参数较多等特点,在声波/弹性波隐身衣、声学波导、声学超构表面等声波调控领域具有潜在应用。由单质材料组成的五模超构材料可以被看作是布拉格散射型的声子晶体,其工作频率在高频波段,而目前针对低频声波调控的五模超构材料的研究还比较少。从3个部分介绍局域共振型五模超构材料的低频声波调控方法和研究进展:首先,对五模超构材料的基本概念及国内外研究现状进行介绍;其次,对两种局域共振型五模超构材料的设计及数值计算过程、能带结构及带隙调控方法进行介绍;最后,对五模超构材料的样件加工技术及测试手段进行介绍,并对局域共振型五模超构材料研究中亟待解决的科学及工程问题进行总结及展望,期望为后续五模超构材料在低频声波控制领域的研究及工程应用提供参考。

Pentamode metamaterial(PM)is a kind of artificial microstructure with a solid structure and the characteristic of"fluid".Due to the better uncoupling property of compressional and shear waves,lower filling rate,multitudinous lattice structures and more adjustable parameters,it has potential applications in acoustic wave regulation fields,such as acoustic/elastic wave cloak,acoustic waveguide and acoustic metasurface.The PM composed of elemental materials can be regarded as a Bragg scattering phononic crystal,whose operating frequency is in a high-frequency range.However,there are few studies focusing on the PM which regulated the low-frequency acoustic waves.In this paper,the low-frequency acoustic wave tuning methods and research progress of locally resonant PMs are introduced in three aspects.Firstly,the basic concepts and research progress of PMs are expounded.Secondly,the designing and numerical calculation process of locally resonant PMs,band structure and phononic band gaps(PBGs)control methods,sample processing and testing methods are introduced in detail.Finally,the scientific and engineering problems that need to be solved urgently in the research of locally resonant PMs are analyzed and discussed.By this way,it is expected to provide a reference for the research and engineering applications of PMs in the field of low-frequency acoustic control.