浅海海域圆柱壳形换能器瞬态辐射声场

发布时间：2018-04-28 17:15

本文选题：频散 + 浅海　；参考：《厦门大学》2014年硕士论文

【摘要】：指向性声源在水声工程中被大量使用,如圆柱形换能器作为发射机被广泛应用于水声通讯系统,故对海下指向性声源瞬态辐射声场作深入研究非常必要。然而,长期以来,关于水下声源辐射声场的研究多集中于无指向性点源所辐射声场,而关于水下指向性声源瞬态辐射声场的研究较为匮乏。本文将围绕浅海水下圆柱壳式换能器瞬态辐射声场展开研究。由于获得一些常用水下指向性声源的势函数并非易事,故本文在研究水下圆柱壳形换能器瞬态辐射声场时,采用瞬态矢量位移波动方程,而非瞬态声压波动方程。在此基础上,首先,导出均匀浅海中简谐波频散方程,通过数值计算对不同深度浅海中导波频散特性进行分析；然后,利用本征函数展开法(简正波法)导出均匀浅海中圆柱壳形换能器瞬态辐射声压解析解,进一步,通过数值计算得到圆柱壳形换能器瞬态辐射声场幅度的空间分布,以及瞬态径向位移,瞬态轴向位移和瞬态声压的时域波形。最后,导出分层浅海中简谐波频散方程,并进行求解,此外,导出了分层浅海中圆柱壳形换能器瞬态辐射声场解析解。本文创新点在于采用本征函数展开法(简正波法)对瞬态矢量位移波动方程进行求解,导出了形式简洁,物理概念清晰的水下圆柱壳形换能器瞬态辐射声场解析解。论文研究成果对水声通讯等实际应用具有一定的理论参考价值。
[Abstract]:Directional sound sources are widely used in underwater acoustic engineering, such as cylindrical transducers, which are widely used in underwater acoustic communication systems. However, for a long time, the research on the acoustic field of underwater acoustic source is mostly focused on the acoustic field radiated by the point source without directivity, but the research on the transient radiation field of the underwater directional sound source is relatively scarce. In this paper, the transient radiation sound field of underwater cylindrical shell transducers in shallow water is studied. Since it is not easy to obtain the potential functions of some commonly used underwater directional sound sources, the transient vector displacement wave equation, rather than the transient acoustic pressure wave equation, is used to study the transient radiation sound field of underwater cylindrical shell transducer in this paper. On this basis, first of all, the simple harmonic dispersion equation in homogeneous shallow water is derived, and the dispersion characteristics of guided waves in shallow water with different depths are analyzed by numerical calculation. By using the eigenfunction expansion method (the normal wave method), the analytical solution of the transient radiation sound pressure of the cylindrical shell transducer in the shallow water is derived. Furthermore, the spatial distribution of the amplitude of the transient radiation sound field of the cylindrical shell transducer is obtained by numerical calculation. And transient radial displacement, transient axial displacement and transient acoustic pressure in time domain waveform. Finally, a simple harmonic dispersion equation in a stratified shallow sea is derived and solved. In addition, an analytical solution to the transient radiation sound field of a cylindrical shell transducer in a stratified shallow water is derived. The innovation of this paper lies in the solution of the transient vector displacement wave equation by using the eigenfunction expansion method (the normal wave method), and the analytical solution of the transient radiation sound field of the underwater cylindrical shell transducer is derived, which is simple in form and clear in physical concept. The research results of this paper have certain theoretical reference value for practical applications such as underwater acoustic communication.
【学位授予单位】：厦门大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：P733.2

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