【作者】 房鑫盛； 殷学文； 王纬波； 吴文伟；

【Author】 FANG Xinsheng;YIN Xuewen;WANG Weibo;WU Wenwei;Taihu Laboratory of Deepsea Technological Science;China Ship Scientific Research Center;

【机构】 深海技术科学太湖实验室； 中国船舶科学研究中心；

【摘要】 兼顾水下低频及宽带吸声的声学覆盖层是提升水下航行器综合隐身性能的有效手段。本文提出一种适用于水下低频段的近完美吸声体,其由嵌入周期性圆柱空腔的黏弹性介质和钢背衬组成,且具备深亚波长厚度。基于等效介质法(Effective Medium Approach, EMA)和遗传算法(Genetic Algorithm, GA)可实现低频可调型吸声体的逆向设计。此外,将多层空腔谐振型黏弹性介质串联有利于充分发挥结构内部的局域共振耦合效应和多重散射效应,提高宽频带下纵波向剪切波的转化效率,进而构建水下宽频吸声体。本文提供了一种新的思路用以设计兼顾低频及宽频段吸声的覆盖层,对于水下轻量化吸声体的研发具有重要意义。更多还原

【Abstract】 The anechoic coating capable of absorbing sound energy in low frequencies within broadband is essential to conceal underwater vehicles. In this work, the quasi-perfect absorber with deep subwavelength thickness has been proposed for low frequency, which consists of a viscoelastic medium embedded with the periodic cylindrical cavities and a steel backing. Based on the Effective Medium Approach(EMA) and Genetic Algorithm(GA), the reverse design of the adjustable anechoic coating could be realized. In addition, the tandem multilayer viscoelastic medium has been demonstrated for the broadband sound absorption. Note that the local resonance coupling and the multiple scattering effects could efficiently convert the longitudinal waves into shear waves. This paper provides a new idea for the design of the low-frequency and broadband anechoic coatings,which is of significance for the development of lightweight underwater sound absorbers.更多还原