面向声目标的水下椭圆柱壳激励声场分布特性研究

The application of underwater vehicles is increasing, and the cylindrical shell is widely used as the main structure of underwater vehicles. Studying the acoustic target characteristics of the cylindrical shell structure is of great significance for the effective detection and identification of underwater vehicles. The application of cylindrical shell structure is the earliest and most extensive, and the research on its acoustic radiation and acoustic scattering is also comparatively mature. The application of elliptical cylindrical shells for underwater structures is also increasing, but the research on the acoustic target characteristics of submerged elliptical cylindrical shells is still quite scarce. In this project, the submerged elliptical cylindrical shell is taken as the research object and the acoustic-structural coupling theoretical models of submerged elliptical cylinder shell with force excitation, sonic excitation and co-excitation are established respectively. A semi-theoretical and semi-numerical solution method based on precise transfer matrix method with odd-order expansion and complex vector virtual boundary spectrum method is proposed. At the same time, numerical simulation and model test are combined to analyze the acoustic target characteristics of submerged elliptical cylindrical shells. The intrinsic physical relationship between the acoustic target characteristics and the characteristic parameters of the shell and the excitation is revealed. Through the research of this project, the theoretical model of acoustic-structural coupling of submerged elliptical cylindrical shells is theoretically established. The acoustic target characteristics of submerged elliptical cylindrical shells are analyzed systematically. Furthermore, the research results can also be used to guide the acoustic design and active-passive detection of underwater elliptical cylindrical shell vehicles, which has important theoretical significance and application value.

水下潜航器应用日益增多，柱壳结构广泛应用于潜航器的主体结构设计，研究柱壳结构的声目标特性对有效探测识别水下潜航器具有重要意义。圆柱壳结构应用最早也最广泛，有关其声辐射与声散射的研究已较为完善。椭圆柱壳在水下潜航器中的应用也日益增多，但关于水下椭圆柱壳声目标特性的研究至今仍较为匮乏。本项目以水下椭圆柱壳为研究对象，分别建立水下椭圆柱壳在力激励、声波激励及共同激励下的声固耦合理论模型，提出基于奇次扩容精细传递矩阵法和复数矢径虚拟边界谱方法的半理论半数值求解方法，同时结合数值计算和模型实验系统分析水下椭圆柱壳声辐射与声散射的声场分布特征，揭示壳体及激励参数与其声场分布之间的内在物理联系。通过本项目研究，在理论上建立水下椭圆柱壳的声固耦合理论模型，系统分析水下椭圆柱壳激励声场分布特性，研究成果可用于指导水下椭圆柱壳潜航器的声学设计及主被动探测识别，具有重要的理论意义和工程应用价值。

随着我国智慧海洋战略的提出，对具备不同功能的潜航器需求大幅增加，同时对潜航器的功能和声学性能指标也提出更高的要求。得益于椭圆柱壳潜航器良好的操纵性能和空间布局能力，椭圆柱壳结构在水下潜航器设计领域的应用日益增多。与此同时，国外水下潜航器的应用也大幅增加，对我国军事目标进行探测侦查，调查我国近海海域水文参数。因此，水下潜航器的声学设计和声目标探测识别具有迫切的现实需求。项目以水下椭圆柱壳声场分布为研究对象，建立水下椭圆柱壳声辐射与声散射理论模型并提出基于奇次扩容精细传递矩阵法和复数矢径虚拟边界谱方法的半解析半数值求解方法，同时结合数值计算和模型实验等手段系统分析椭圆柱壳结构的水下声辐射与声散射特性，揭示壳体及激励源参数与其场分布特性之间的内在物理联系，为水下椭圆柱壳的结构声学设计及探测识别提供理论依据。.椭圆柱壳关于长轴和短轴对称，且对称和反对称模态频率及振型不同；椭圆度对壳体振动的影响主要在低频域，激励沿着长半轴方向激励的振动相对较小，沿着短半轴方向激励的振动较大；椭圆柱壳的声压指向性呈现出明显的分瓣现象，频率低声压分瓣数少，频率高声压分瓣数多，在激励点一侧，辐射声压较大且分瓣数也较多；平面波的入射角度对声压指向性有明显的影响，当入射角为0°时，声压指向性关于椭圆柱轴线对称，在0°波干涉最弱，而在158°和202°左右干涉较为明显；椭圆柱壳正横方向声目标强度较大，90°方向目标强度较小；在力激励与声波激励作用下，力激励产生的辐射噪声主要影响低频段，声激励主要影响高频段，力激励与声波激励共同作用下可分别进行计算再叠加。通过椭圆柱壳的水下声辐射和声散射实验验证了本研究理论模型和求解方法的准确性。通过本项目的研究，一方面可以进一步丰富水下柱壳结构的声学特性研究体系，另一方面可指导水下椭圆柱壳潜航器的声学设计以及探测识别，项目研究具有重要的理论意义和工程应用价值。.