一种含圆柱形谐振散射体的黏弹材料低频吸声机理研究

利用层多重散射法分析了一种含圆柱形谐振散射体黏弹 材料吸声层在钢背衬条件下的低频吸声特性. 该吸声层由包覆软材料的圆柱空腔周期嵌入橡胶材料中构成, 其中, 散射体轴线与吸声层平行. 结果表明, 20 mm厚吸声层在1000–3000 Hz具有良好的吸声性能. 通过综合分析单个散射体的吸收截面、单层周期散射体的声吸收、 结构内部位移场以及耗散功率密度分布, 揭示了该吸声层的低频吸声机理.关键词：水声吸声吸收截面耗散功率密度

Low-frequency acoustic absorption mechanism of a viscoelastic layer with resonant cylindrical scatterers

This paper investigates low-frequency acoustic absorption mechanism of a viscoelastic layer with resonant cylindrical scatterers. The viscoelastic layer is 20 mm-thick, and the cylindrical scatterer is a cylindrical cavity coated with a soft rubber layer, with axis in the lateral layer direction. The absorption properties of the viscoelastic layer under the steel-backing condition are studied using the layer-multiple scattering method. Results show excellent absorption performance in the frequency region of 1000–3000 Hz. The absorption mechanism is investigated by analyzing the absorption cross-section of a single scatterer and the multiple scattering of a periodic array of scatterers, together with the displacement field and power dissipation density. Effects of the resonant absorption of a single scatterer and the coupling resonance between the absorption layer and the steel-backing are revealed.
Keywords：underwater acoustic absorptionabsorption cross-sectionpower dissipation density