单面柱局域共振声子晶体低频带隙特性分析及结构改进研究

Characteristic Research of Low Frequency Band Gaps and Structural Improvement in Single-Sided Column Local Resonance Phononic Crystals

基于有限元法对单面柱局域共振声子晶体进行带隙特性分析,研究了结构参数对该类型声子晶体的影响。结果表明:随着散射体高度的增加,单面柱声子晶体的第一完全带隙的起始频率逐渐降低,带宽逐渐增大;随着基板厚度的增大,单面柱声子晶体的起始频率逐渐升高,截止频率先增大后减小。并且在经典单面柱声子晶体的基础上,组合了两种新型的三组元单面柱声子晶体结构:嵌入式单面柱声子晶体(以下简称结构Ⅰ)和粘接式单面柱声子晶体(以下简称结构Ⅱ)。通过对其带隙特性的分析得出:这两种新结构与经典的单面柱声子晶体相比,都具有更低频的带隙,这对于低频减振降噪是非常有利的。本文的结果将对实际的工程应用提供一定的理论指导。

Based on the finite element method,the band gap of the phononic crystal in single-sided cylinder local resonance was analyzed,and the influence of structural parameters on the phononic crystal was studied.The results show that the initial frequency of the first complete band gap decreases and the bandwidth increases with the increase of the height of the scatterer.With the increase of the thickness of the substrate,the initial frequency of the single-sided cylindrical phononic crystal increases gradually,the cut-off frequency first increases and then decreases.In addition,based on the classical single-sided cylindrical phononic crystal,two new ternary single-sided cylindrical phononic crystal structures are combined:embedded single-sided cylindrical phononic crystal(Hereinafter referred to as structureⅠ)and bonded single-sided cylindrical phononic crystal(Hereinafter referred to as structureⅡ).Through the analysis of the band gap characteristics,it is concluded that the two new structures have lower frequency band gap compared with the classical single-sided cylindrical phononic crystals,which is very beneficial for low-frequency vibration and noise reduction.The results of this paper will provide some theoretical guidance for practical engineering application.