敷设空腔覆盖层水下复杂目标的声散射特性研究  

Acoustic scattering characteristics of underwater complex targets covered with cavity structural anechoic coating layer

作　　者：李静 马晓川[1,2,3] 李璇[1,2,3] LI Jing;MA Xiaochuan;LI Xuan(Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;Key Laboratory of Information Technology for AUVs,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院声学研究所,北京100190 [2]中国科学院水下航行器信息技术重点实验室,北京100190 [3]中国科学院大学,北京100049

出　　处：《声学技术》2023年第4期409-418,共10页Technical Acoustics

基　　金：中国科学院声学研究所自主部署"前沿探索"类项目(QYTS202013)。

摘　　要：研究敷设空腔覆盖层水下复杂目标的声散射特性具有重要的意义。首先通过建模软件构建目标模型,然后利用分层近似法,结合多层介质的传递矩阵方法,将含有变截面空腔的吸声覆盖层分为多个可视为圆柱空腔结构的薄层,进而实现复合结构的声反射系数的求解,最后利用基于戈登(Gordon)积分的板块元方法对目标强度进行预报,并针对复杂目标提出基于光线投射的可见面元判别方法。在此基础上,以BeTSSiⅡ标准模型为例,研究敷设空腔覆盖层的水下复杂目标的声散射方位特性和频率特性。结果表明:文中提出的基于光线投射的可见面元判别方法可以快速有效地提供板块元方法所需的可见面元;板块元方法对BeTSSiⅡ标准模型的预报结果可以很好地反映其目标强度的特征及其变化规律;模型敷设空腔覆盖层可以有效降低目标强度,与敷设等厚均匀覆盖层时相比,复合结构声反射系数曲线的第一谷值频率降低,在频率较低时敷设空腔覆盖层的吸声效果更好,可以进一步减小目标强度。该研究有助于实际工程中实现对水下平台散射特性的快速预报。It is of great significance to study the acoustic scattering characteristics of complex underwater target with cavity structural anechoic coating layer.Firstly,the complex underwater target model is established by modeling software.Then,the cavity with variable cross sections is divided into several thin segments that can be regarded as the cylindrical cavity structure.The acoustic reflection coefficient is calculated by using the segment approximation method and the transfer matrix method of stratified medium.Finally,the target strength of the model is calculated according to the planar element method based on the Gordon integral.In addition,a ray-casting-based visible facet discrimination method is proposed for complex targets.Taking the BeTSSiⅡmodel as an example,the influence of the incident azimuth and frequency of the acoustic wave on the acoustic scattering characteristics of the model is studied.The results show that the ray-casting-based visible facet discrimination method proposed in this paper can quickly and effectively provides the visible facets required by the planar element method;the calculation results of the BeTSSiⅡmodel by the planar element method can well reflect the characteristics and regularities of its target strength;laying a cavity structural anechoic coating layer on the model can effectively reduce the target strength.Furthermore,compared with laying a uniform anechoic coating layer of equal thickness,the frequency of the first valley of the acoustic reflection coefficient curve of the composite structure decreases,which results in better sound absorption at low frequencies and can further reduce the target strength.The research in this paper is helpful for the realization of rapid prediction of the scattering characteristics of underwater platform in practical engineering.

关 键 词：目标强度 声散射 板块元 空腔覆盖层 戈登(Gordon)积分 

分 类 号：TB56[交通运输工程—水声工程]