论文部分内容阅读
声子晶体是一种具有弹性波带隙特性的周期性复合材料,其带隙特性受单胞拓扑形状的影响.通过拓扑优化技术,能够突破传统设计方法的局限,实现对声子晶体的主动设计.论文基于遗传算法和改进的平面波展开法,通过两阶段的优化过程,得到具有最大相对带隙的二维铜/环氧树脂声子晶体结构,并进一步研究不同带隙最优声子晶体单胞拓扑形状及其带隙特性.结果表明,利用所开发的带隙优化程序,能够得到满足带隙要求的具有全局最优的声子晶体结构;声子晶体最低带隙所对应的单胞是简单晶格结构,其散射体形状简单,而且对应的带隙频率最低,相对带隙最大,对于隔音减振最有实用价值.
The phonon crystal is a kind of periodic composite material with elastic bandgap characteristic, and its bandgap characteristic is affected by the shape of the cell topography.Through the topology optimization technology, it can break through the limitation of the traditional design method and realize the phonon crystal active Design.Based on the genetic algorithm and the improved plane wave expansion method, a two-dimensional copper / epoxy phononic crystal structure with the largest relative bandgap was obtained through two-stage optimization process. The topological shape of the cell and the bandgap characteristics of the phonon crystal.The results show that the optimized global optimum bandgap phononic crystal structure can be obtained by using the developed bandgap optimization program.The single cell corresponding to the lowest bandgap of the phononic crystal Is a simple lattice structure, the shape of the scatterer is simple, and the corresponding bandgap frequency is the lowest, with the largest relative bandgap, which has the most practical value for noise damping.