局域共振二维声子晶体的低频带隙特性研究  

Low-frequency Band Gap Characteristics of Locally Resonant Two-dimensional Phononic Crystal

作　　者：梁孝东 缪林昌[1] 尤佺 厉超 方黄磊 雷利剑 LIANG Xiao-dong;MIAO Lin-chang;YOU Quan;LI Chao;FANG Huang-lei;LEI Li-jian(School of Transportation,Southeast University,Nanjing 211189,China)

机构地区：[1]东南大学交通学院

出　　处：《人工晶体学报》2019年第7期1225-1232,共8页Journal of Synthetic Crystals

基　　金：国家自然科学基金(51578147)

摘　　要：针对低频带隙难以打开的问题,本文提出一种局域共振二维声子晶体结构,采用有限元法计算其能带结构,分析其带隙的形成机理和影响因素,并在此基础上对结构进行优化设计。结果表明:该结构可在200Hz以下的频率范围内打开宽度70.56Hz的完全带隙,起始频率低至39.77Hz。等效刚度k一定的情况下,带隙起始频率由芯体的密度决定,而截止频率主要由基体边框密度决定。优化后的结构能够打开更低更宽的带隙,且对振动波的衰减性能提升。该结构具有优越的低频带隙特性,在地铁减振隔振领域中具有潜在的应用前景。A type of locally resonant two-dimensional phononic crystal structure was proposed to overcome the difficulty of opening the low-frequency band gap.By the finite element method,the band gap structure was calculated.The formation mechanism and influencing factors of the band gap were analyzed,and the structure was optimized on this basis.The results show that,the structure can open a complete band gap with a width of 70.56 Hz in the frequency range below 200 Hz,and the starting frequency is as low as 39.77 Hz.When the equivalent stiffness k is constant,the starting frequency is determined by the density of the core,while the cut-off frequency is mainly determined by the density of the matrix.The optimized structure can open lower and wider band gap and improve the attenuation performance of vibration wave.The structure has excellent low-frequency band gap characteristics and has potential application prospects in the field of subway vibration attenuation and isolation.

关 键 词：减振隔振 声子晶体 局域共振 影响因素 优化设计 

分 类 号：TB123[理学—工程力学]