Membrane cavity coupling type underwater acoustic board

Abstract

The invention aims to provide an underwater sound absorption structure with a good low-frequency sound absorption effect. The average sound absorption coefficient of the sound absorption structure canreach 0.7 or above within the frequency range of 3000Hz. The invention relates to an underwater low-frequency sound absorption structure, in particular to a membrane cavity coupling type underwater acoustic board, which comprises an installation layer, a sound absorption layer and a structure cavity. The average sound absorption coefficient of the sound absorption structure can be 0.7 or above within the frequency range of 3000Hz. The sound absorption layer and the installation layer are laminated and bonded, wherein a plurality of structural cavities are formed in the sound absorption layer,each structural cavity is one or a combination of two of a double-horn shape or a vase shape with the gradually-changed hole diameter, the lower surface of each structural cavity is flush with the bottom surface of the sound absorption layer, a film structure is arranged in each structural cavity, and an asymmetric mass block is arranged on the film structure.

Description

technical field [0001] The invention relates to an underwater low-frequency sound-absorbing structure, in particular to a membrane cavity coupling type underwater sound-absorbing panel. Background technique [0002] As an effective underwater sound-absorbing structure, the sound-absorbing panel can not only control the radiated noise of the ship, but also resist active sonar detection. The sound-absorbing panel is light in weight and small in size, which meets the structural design requirements of light weight and high efficiency for ship noise reduction. [0003] For the surface sound-absorbing coating of underwater vehicles, rubber damping materials are mainly used at present. Because the low-frequency sound-absorbing performance of a uniform single material is not ideal, and is limited by the law of mass density, traditional underwater sound-absorbing materials are not effective in the low-frequency range. It is not good enough to meet the sound absorption requirements of...

AI Technical Summary

Problems solved by technology

At present, a lot of research has been done on resonant cavity underwater sound-absorbing materials at home and abroad. On the basis of cylindrical cavities, the size and shape of the cavities are optimized, and frustum-shaped cavities (CN102354493) and conical cavities (CN200620149617) are obtained. .3), trumpet-shaped cavity (CN200620049330.0) and spiral rigid structure (CN208256285U) and other resonant cavity structures of various shapes, although most of them can effectively absorb sound waves above 5KHz underwater with a small size , but not good for lower frequency sound waves

Therefore, although some progress has been made in the research of underwater sound-absorbing materials, so far, an effective underwater low-frequency sub-wavelength sound-absorbing structure has not been proposed.

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