带隙特性是声子晶体材料和结构的一个重要特征, 在材料的隔振、隔声和滤波等领域具有潜在的应用价值。控制和调整周期性微结构内的材料布局及属性, 可以设计出所需特殊带隙要求的声子晶体。本文通过遗传算法和拓扑优化技术研究了一维三相声子晶体的优化设计, 并给出了两个算例研究。结果表明, 三相材料能够得到更好的隔振效果, 对比两相材料, 三相声子晶体能够大幅降低禁带频率, 并得到高达99.21%的禁带。可见, 利用进化算法进行多相声子晶体的拓扑优化设计是可行的。

Existence of bandgap is an important characteristic of the periodic materials or structures, which has potential use in the development of vibration/sound isolation and frequency filters. By controlling and adjusting the material layout and properties in the periodic microstructure, phonon crystals with special bandgap requirements were designed. In this paper, the optimal design of one-dimensional three-phase phnononic crystals were investigated by genetic algorithm and topology optimization technique and two examples were presented. The results show that three-phase materials can achieve better vibration isolation effect and will reduce the bandgap frequency greatly compared with the two-phase materials, even get up to 99.21% forbidden band. Therefore, it is feasible to use evolutionary algorithm to optimize and design the topology of multi-phase phononic crystals.