利用有限元法研究散射体对一维声子晶体板中声信号传播的调控作用

Finite Element Investigation on Acoustic Waves Propagating in One-dimensional Phononic Crystal plates

声子晶体是一种新型的人工复合周期性材料,其几何参数和材料参数对声信号能带结构有着很大的影响。文章运用有限元的方法计算分析基体为硅时,散射体材料分别为钨和金时的能带结构,结果表明,材料参数对声信号带隙位置有显著影响,散射体为金的带隙比散射体为钨的带隙窄,通过比较具有圆柱形和正四棱柱形散射体样品板中声波的能带结构,发现散射体的形状对低频范围内声信号的禁带分布也有很大影响。

Phononic crystal is a new kind of artificial composite material, whose geometric parameters and material parameters have significant influence on the band structure of acoustic waves. The band structure of one-dimensional （1D） phononic plates composited with silicon as matrix and tungsten/gold as scatterer is calculated by finite element method. The results show material parameters affect a lot on the location of band gaps of acoustic waves. The band gap width of acoustic waves propagating in the plate with golden scatterers is narrower than the case with tungsten one. It is found that the band structure of acoustic waves changes obviously along the variation of the pattern of scatterers.