五模声学超表面理论分析与定向反射声学仿真

Theory analysis and acoustics simulation of reflection pentamode acoustic metasurface

以广义斯奈尔定律为理论依据,对五模声学超表面定向反射的基本原理进行了解析推导和理论分析,获得了五模超表面的理想连续物性参数分布,并给出了五模超表面尺寸设计准则;然后将超表面离散,获得离散单胞的密度和体积模量,并以此为目标进行五模微结构设计,采用均匀化理论计算微结构的等效物性参数;最后,进行了水下声场的声波定向反射调控仿真实验,研究了入射波频率对超表面定向反射性能的影响,仿真结果展现了五模超表面宽频有效的声波调控能力以及调控的可靠性和准确性。该文的研究工作为五模声学超表面的设计和物理实现提供理论指导。

Based on the generalized Snell’s law,the derivation and theoretical analysis of the fundamental principles are carried out for directional reflection pentamode acoustic metasurfaces.The basic criteria for the design of dimensions of reflective pentamode metasurfaces are proposed,and a pentamode acoustic meatsurface with gradient-distributed physical parameters is designed.Then,the continual metasurface is discreted to get mechanical properties of unit cells which are as optimization design aims of pentamod microstructure.The effective bulk modulus and density of pentamode structures are calculated using homogenization method Finally,multi-physics field simulation software is utilized to simulate directional wave reflection control for the metasurface under the background of water field.The simulation studies the influences of incident wave frequency on the directional reflection performances of the metasurface.The results of simulation exhibit the pentamode metasurface’s broadband and high-effective abilities for acousitc waves manipulation,as well as the reliability and accuracy of manipulation.The research work in this paper can provide theory guidance for the design and physical implementation of the pentamode acoustic metasurfaces.