局域共振型腔体结构吸声瓦的斜入射吸声特性研究  

Sound absorption characteristics of acoustic tiles with local resonance cavity structure under oblique incidence

作　　者：王佳蓓 周浩[1] WANG Jiabei;ZHOU Hao(College of Weapons Engineering,Naval University of Engineering,Wuhan 430033,China)

机构地区：[1]海军工程大学兵器工程学院,武汉430033

出　　处：《振动与冲击》2022年第6期265-270,297,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(11602300)。

摘　　要：吸声瓦的吸声特性对于水下航行器的声隐身性能具有重要影响。综合考虑空腔覆盖层的结构和局域共振型薄膜材料的低频吸声性能,利用COMSOL软件建立了局域共振型腔体结构的吸声瓦的有限元模型,研究了其在10~2000 Hz内对斜入射声波的吸声性能,采用振动位移云图揭示其吸声机理,通过位移矢量图和动能密度分布图分析入射角度影响吸声性能的原因。研究结果表明:该吸声瓦的吸声系数随频率的增大、斜入射角度的增大而增大;吸声机理为上下空腔的收缩与扩张引起纵波向损耗因子较大的横波转化,以及局域共振结构的反共振消耗声能,二者共同作用提高吸声瓦的吸声性能;斜入射声波使得吸声瓦横向位移增大,转化成的剪切波增多;斜入射角度越大,吸声瓦的动能密度越高,消耗声能越多,因此吸声性能增强。研究结果可为吸声瓦的低频吸声特性设计提供理论指导。The sound absorption characteristics of anechoic tiles have an important effect on the acoustic stealth performance of underwater vehicles.Considering the structure of the cavity covering layer and the low frequency sound absorption performance of local resonance film material,the finite element model of the sound absorption tile with the local resonance cavity structure was established by COMSOL.The sound absorption performance in the frequency band of 10-2000 Hz was studied.The sound absorption mechanism was revealed by the vibration displacement nephogram.The influence of incident angle on the sound absorption performance was analyzed by the displacement vector diagram and kinetic energy density diagram.The results show:(1)the sound absorption coefficient increases with the increase of the frequency and oblique incidence angle.(2)The sound absorption mechanism is as follows:the contraction and expansion of the upper and lower cavities cause the longitudinal wave transform from the P-wave to S-wave which is of rather large loss factor.Moreover,the anti-resonance behavior of the local resonance structure also consumes sound energy.Thus,these two factors work together to improve the sound absorption performance of anechoic tiles.(3)Oblique incident acoustic waves increase the transverse displacement,as well as the shear waves’conversion.The larger the oblique incidence angle is,the higher the kinetic energy density is.More sound energy is consumed,so the sound absorption performance is enhanced.The research results provide theoretical guidance for the design of low frequency sound absorption characteristics of anechoic tiles.

关 键 词：振动与波 局域共振 空腔结构 吸声瓦 斜入射 振动位移 

分 类 号：O429[理学—声学]