幂指数棱台局域共振型声子晶体板的带隙特性与减振机理研究  

Band gaps characteristics and vibration reduction mechanism of powerexponential prismatic local resonance phononic crystal plates

作　　者：金星[1] 张振华[1] JIN Xing;ZHANG Zhenhua(College of Naval Architecture and Ocean,Naval University of Engineering,Wuhan 430033,China)

机构地区：[1]海军工程大学舰船与海洋学院,武汉430033

出　　处：《振动与冲击》2023年第14期107-114,179,共9页Journal of Vibration and Shock

基　　金：国家自然科学基金(51879270)。

摘　　要：针对船体板结构的振动控制,提出了一种新型幂指数棱台局域共振型声子晶体构型。研究表明,该声子晶体兼具局域共振低频带隙和声学黑洞高频带隙,对高频激励和低频激励均有较好的减振效果。声子晶体其低频带隙因共振单元的局域共振效应产生,带隙频段为78~115 Hz。在声子晶体能带结构的高频段中发现了隐藏于平直带的U型频散曲线,且频散曲线间的频段可有效抑制板的垂向振动,即产生垂向高频振动带隙。高频带隙产生的机理是幂指数棱台斜面的能量聚集效应形成的局域共振。随着散射体高度增大,低频带隙的中心频率降低,且带宽增大。棱台的幂次升高会使高频带隙的起始频率与终止频率降低,而边缘厚度的增高会使高频带隙的带宽逐渐变窄。新型声子晶体相较传统声学黑洞构型可有效提高船体板结构强度,从而可实际应用于船舶结构工程领域。研究成果可为舰艇结构振动控制提供支撑。The hull plate with a new form of phononic crystals was proposed and construced.It is found that the low frequency bandgap and high frequency bandgap can both lead to the vibration reduction of a thin-slab structure.The low frequency bandgap of phononic crystals was produced by the locally resonant mechanism,and there is a bandgap in a frequency range of 78-115 Hz.The U-shaped dispersion curve hidden in the flat band is found in the dispersion curves of phononic crystals.The frequency band between the U-shaped dispersion curves can effectively reduce the vertical vibration of the plate.The mechanism of high-frequency band gap generation is a local resonance formed by the energy aggregation effect of a power exponential prismatic slope.The height of the scatterer is the most important factor in the low frequency bandgap.The shape of basal body has no effect on the low frequency bandgap,but has great effect on the high frequency bandgap.With the increase of scatterer height,the center frequency of the low frequency band gap decreases.Increasing the power will decrease the start frequency and stop frequency of the high frequency bandgap.Increasing the edge thickness will gradually decrease the bandwidth of the high frequency bandgap.Compared with the traditional acoustic black hole,the new form of phononic crystals can effectively improve the structural strength of the hull plate,which presents a certain guiding value in ship structure engineering.The results obtained provide a reference for the structural vibration control of warships.

关 键 词：声子晶体 带隙 局域共振 

分 类 号：TB535[理学—物理]