二维正方晶格多点缺陷声子晶体实验研究

基于超声浸水透射技术, 实验研究了有限尺寸二维正方晶格钢/水声子晶体多点缺陷模态性质. 利用COMSOL Multiphysics软件建立该声子晶体有限元计算方法, 求解了9×9超胞多点缺陷声子晶体能带结构, 把缺陷局域模态频率与数值仿真和实验结果进行对比, 结果表明: 实验数据和理论值能够很好符合. 进一步分析发现, 点缺陷数量影响声波局域效应、本征模态和传播特性, 为设计有限尺寸声波器件提供理论依据. 关键词： 声子晶体 多点缺陷 实验研究 有限元

Experimental investigation of two-dimensional multi-point defect phononic crystals with square lattice

The characteristics of multi-point defect phononic crystal (PC) composed of square array of circular steel cylinders in water are investigated experimentally using the ultrasonic immersion transmission technique. The band structures of the PCs are obtained by the finite element method with 9×9 supercell approximation. A very good agreement with the experimental results, numerical transmission data and eigenmode frequencies of band structures is observe. Meanwhile the number of multi-point defects affects the localized modes of cavities and propagation characteristics, and the eigenmodes of defects show the symmetric or antisymmetric modes in designing the new type of acoustic wave devices.
Keywords： phononic crystals multi-point defects experimental investigation finite element method