Estimation of Absorption Performance of Underwater Anechoic Coating by Multilayer Arrangement of Cylindrical Cavity

Abstract

Rubber coatings with inner cavities are often used as underwater anechoic coatings. What is important in improving the underwater absorption performance is to improve the low frequency absorption performance, while satisfying the broadband absorption performance. Generally the homogenous medium can hardly satisfy the broadband absorption performance. In this paper sound absorption coatings with new arrangement of cavities to satisfy both broadband absorption performance and better low frequency absorption performance is presented. We proved that the absorption coating with the multilayer arrangement has much higher absorption performance than single layer structure and evaluated the absorption performance in the case of variation of the number of inner cavities and method of cavity arrangement in the multilayer arrangement conformation.