A novel underwater composite anechoic layer is proposed by inserting periodically placed longitudinal parallel steel plates into a viscoelastic rubber matrix. Built upon the complex viscosity model of viscoelastic materials, a theoretical model is established to evaluate the sound absorption performance of the proposed anechoic layer. For validation, finite element simulations are carried out, and good agreements are achieved between theory and simulation. Compared with the reference structure purely made of rubber, the new anechoic layer exhibits greatly improved sound absorption performance. It is demonstrated that the steel plate insertions significantly enlarge the shear deformation of rubber at plate–rubber interfaces, causing greatly improved viscous dissipation of acoustic energy. Systematic variations of material properties and geometrical parameters reveal the dominant roles of rubber viscosity and plate spacing. Further, a theoretical model is developed to study the effect of non-tight connection at rubber–plate interfaces. This study broadens the application scope of the complex viscosity model and provides useful guidance for designing novel anechoic layers with tailored underwater acoustic performances.

通过将周期性放置的纵向平行钢板插入粘弹性橡胶基质中，提出了一种新型水下复合消声层。基于粘弹性材料的复粘度模型，建立了一个理论模型来评估所提出的消声层的吸声性能。为了验证，进行了有限元模拟，并且在理论和模拟之间取得了良好的一致性。与纯粹由橡胶制成的参考结构相比，新型消声层的吸声性能大大提高。结果表明，钢板插入显着扩大了橡胶在板 - 橡胶界面处的剪切变形，从而大大改善了声能的粘性耗散。材料特性和几何参数的系统变化揭示了橡胶粘度和板间距的主导作用。此外，还开发了一个理论模型来研究橡胶-板界面处非紧密连接的影响。这项研究拓宽了复粘度模型的应用范围，并为设计具有定制水声性能的新型消声层提供了有用的指导。