A method for calculating a complex structure radiation sound field in a marine acoustic channel

Abstract

The invention discloses a method for calculating a complex structure radiation sound field in a marine acoustic channel, and belongs to the technical field of acoustic numerical calculation. The limitation that a traditional boundary element method is only suitable for free field sound field calculation is broken through, and a sound field Green function in an ocean sound channel is established. Ahierarchical matrix compression technology is adopted to divide a radiation impedance matrix into a series of hierarchical matrix blocks with different sizes, and an iteration method is further utilized to solve a matrix equation. Compared with the prior art, the method has the effects and benefits that the acoustic calculation function of the traditional boundary element method is expanded frominfinite uniform media to the bounded space of the ocean channel, and the influence of sea surface, seabed boundary and sound velocity gradient distribution can be considered. And on the other hand, the radiation impedance matrix is subjected to hierarchical compression, the consumption of a computer memory is greatly reduced by utilizing the low-rank characteristic approximate decomposition of the matrix block, the influence of the diversity of a sound field Green function under the complex marine channel condition is avoided, and the algorithm adaptability is good.

Description

Technical field [0001] The invention relates to an acoustic numerical calculation method, in particular to a fast boundary element calculation method for the radiated sound field of a complex structure in a marine acoustic channel. Background technique [0002] The ocean acoustic channel has a great influence on the shell vibration and acoustic radiation. The calculation needs to consider the reflection and absorption of the bottom and water surface. The calculation of far-field propagation depends more on the acoustic channel factors such as the sound velocity gradient distribution in the sea area and the sea surface and seabed geological conditions. This makes the calculation of the sound field radiated by the structure in the ocean channel difficult. [0003] In the prior art, people have separately studied the calculation of the sound field radiated by complex structures and the propagation of sound waves in ocean channels. The former treats the seawater medium into an ideal u...

AI Technical Summary

Problems solved by technology

However, the traditional acoustic boundary element method has the following disadvantages: (1) The free-field Green’s function used in the traditional boundary element method is not suitable for dealing with the acoustic radiation problem in a bounded space; (2) the node-to-node calculation method adopted by the boundary element method, The amount of calculation is proportional to the cube of the total number of degrees of freedom

When solving large-scale problems, the amount of calculation and storage will increase dramatically, which greatly limits the application of boundary element method in large-scale engineering problems

Therefore, the traditional boundary element method is difficult to use to calculate the complex structure-acoustic radiation problem in the ocean channel environment

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