钢板-空气背衬上含空腔粘弹性材料层的声反射特性

本文研究声波从水中入射到粘弹性材料层-钢板-空气上的反射特性，运用分层介质中的波动理论研究粘弹性层均匀情况的声特性，运用有限元方法研究粘弹性层含空气腔结构情况的声特性。结果表明，改变粘弹性材料消声特性需要综合调整材料的弹性参数；粘弹性层内的空腔结构对声特性产生很大影响，改变其谐振特性和反射系数的收敛特性。文中以含圆锥腔、圆台等复合腔的结构粘弹性层为例，计算了其反射系数的频响特性、谐振模态，并分析了结构的影响。

Sound reflection characteristics of a viscoelastic coating with air cavities adhered to a steel plate between water and air

The reflection characteristics of the viscoelastic layer adhered to a steel plate between water and air are studied when the acoustic wave impinges from water. The waves theory in layered medium is used to study the sound characteristics of the homogeneous viscoelastic layer and the finite element method is applied to analyze the characteristics of the viscoelastic coating containing air cavities. The results show that to change the sound absorption characteristics needs to adjust the material parameters synthetically. The air cavity produces great effect to the sound characteristics of the viscoelastic coating. It changes the resonance characteristics and the convergent characteristics of the reflection coefficient. For the coating containing cone cavities or composite cavities such as frustum of a cone, the frequency response of the reflection coefficient and the resonance modes are calculated, and the effect of the structure is analyzed.