平板二维声子晶体声波能带结构研究

Acoustic wave band structure in two-dimensional phononic crystal slab

利用超元胞法,研究由钢板上生长有限长度的钢柱体形成的散射体嵌入环氧树脂基体中所构成的平板二维声子晶体的声波能带结构,分析散射体的几何参数如柱体的高、半径和板的厚度对声波带隙的影响。研究结果表明:(1)这种新型的声子晶体具有很宽的带隙,且带隙出现在低频范围内;(2)散射体的几何参数对带隙的宽度有很大的影响,它们是控制带隙宽度的主要因素。

By using the supercell method, the acoustic wave band structure of two-dimensional phononic crystal slab is investigated. The two-dimensional phononic crystal slab consists of steel cylinders implanted in a steel plate embedded in epoxy where the length of the steel cylinders is limited. The influence of the geometric parameters of the scatterer （the thickness of the slab, the radius and height of the cylinder） on the band structure is analyzed. Our calculated results indicate that this kind of phononic crystal there exist widen band gap and the band gap appear in low frequency range. We also find that the geometric parameters of the scatterer have great effects on the gap widthes and they are the main factors to control the latter.