摘要
基于局域共振理论,提出了一种耦合声学黑洞结构的新型轻质声子晶体,利用声学黑洞结构的低频、宽频带和多模态特性,拓宽了低频带隙。借助有限元方法,计算了新型声子晶体的能带结构、本征模态和衰减特性,研究了其带隙产生机理,分析了声学黑洞结构尺寸等几何参数对带隙的影响规律。结果表明:新型声子晶体在1600 Hz频段内具有多个带隙,第1完全带隙为12~805 Hz,40 Hz以下的带隙覆盖率为70%,1600 Hz内的带隙覆盖率达到97.3%。第1完全带隙的起始频率和截止频率主要由散射体和声学黑洞结构的振动模式决定。第1完全带隙起始频率随着声学黑洞结构短边高度的增加而增大,声学黑洞结构宽度、短边高度以及连接短板高度对截止频率和带隙宽度有显著影响。
A phononic crystal coupled with the acoustic black hole structure was proposed based on the local resonance theory. The low frequency band gap was widened by utilizing the low frequency, broad band gap, and multi-modal properties of the acoustic black hole structure. The energy band structure, eigenmodes and attenuation characteristics of the phononic crystal were calculated by the finite element method. The generation mechanism of its band gap was analyzed, and the influence of the geometric parameters(i.e., the structural parameters of the acoustic black hole) on the band gap was discussed. The results show that the phononic crystal has multiple band gaps at 1 600 Hz, and the first complete band gap ranges from 12 to 805 Hz. The band gap coverage below 40 Hz is 70%, and the band gap coverage within 1 600 Hz reaches 97.3%. The starting and cut-off frequencies of the first complete band gap are mainly determined by the vibrational modes of the scatterer and the acoustic black hole structure. The starting frequency of the first complete band gap increases with increasing the height of the acoustic black hole structure short side. The width and short side height of the acoustic black hole structure and the height of the short plate have an effect on the cut-off frequency and the width of the first complete band gap.
作者
陈俊豪
曾晓辉
谢友均
龙广成
唐卓
CHENG Junhao;ZENG Xiaohui;XIE Youju;LONG Guangcheng;TANG Zhuo(School of Civil Engineering,Central South University,Changsha 410000,China)
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2023年第1期226-234,共9页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金项目(52078490,11790283)。
关键词
局域共振
声学黑洞
声子晶体
低频
完全带隙
local resonance
acoustic black hole
phononic crystal
low frequency
complete band gap