三谐振弹性波超材料的带隙研究

Study on band gaps in elastic wave metamaterials with three-resonators

基于集中参数模型动力学法,研究了具有三谐振系统弹性波超材料能带结构、数值模拟参数对有效质量及能带结构的影响。理论及仿真研究表明,有效质量具有频率依赖性,在3个频率位置处的有效质量为负值,频率位置和带宽可由模型参数调节;材料存在3个带隙,增加内部谐振子弹性系数可将带隙向高频移动,同时有拓宽带隙作用。通过增加谐振子质量可使带隙向低频移动,选择适当参量可设计低频宽带弹性波超材料。

The lumped element model is present to study the band gaps of elastic wave metamaterials with three resonators. The effects of parameters on band structure and effective mass are discussed numerical- ly. The results show that the effective mass tightly depends on frequency. The negative effective mass can be found at three positions on frequency domain. The metamaterial have three band gaps and the larger spring constant can broaden band gaps and shift band gaps to higher frequency domain. As increasing the resonatorrs mass band gaps can be shifted to the low frequency domain. The metamaterial with low fre- quency and broad band can be desigened by property parameters.