Sound absorber with adjustable sound absorption frequency band

Abstract

The invention discloses a sound absorber with an adjustable sound absorption frequency band, and belongs to the technical field of low-frequency sound absorption. The sound absorber comprises a box top, a box body and a box bottom which are sequentially connected with one another; a sound absorption sponge layer, curved surface deformation sound absorption structures and automatic vibration sound absorption structures are sequentially arranged in the box body; the sound absorption sponge layer is located on the inner top wall of the box top; the number of the curved surface deformation sound absorption structures and the number of the automatic vibration sound absorption structures are multiple; each curved surface deformation sound absorption structure comprises a flexible substrate layer, a plurality of sheet electrodes, a control system and a power supply, wherein the plurality of sheet electrodes are distributed on two surfaces or one surface of the flexible substrate layer in a matrix arrangement manner, and the flexible substrate layer is an ion exchange membrane layer; the sheet electrodes are connected with the power supply, and the power supply is connected with the control system, so that the flexible substrate layer deforms. The sound absorber with the adjustable sound absorption frequency band has the advantages of simple structure, small size and adjustable sound absorption performance.

Description

technical field [0001] The invention relates to the technical field of low-frequency sound absorption, in particular to a sound-absorbing body with adjustable sound-absorbing frequency band. Background technique [0002] Low-frequency vibration noise is ubiquitous in modern society, such as the rotating noise accompanied by rotating machinery such as pumps and fans; the radiation noise caused by the low-order resonance frequency of power machinery such as engines, etc. Research on the control and treatment of these noises runs through the entire industry. The traditional porous sound-absorbing material satisfies the linear response theory, and its internal noise attenuation is positively correlated with frequency. Therefore, it has a good sound absorption and isolation effect on medium and high-frequency noise, but its absorption efficiency on low-frequency noise is very low. In recent years, the development of phononic crystals and metamaterials has injected new vitality i...

AI Technical Summary

Problems solved by technology

[0005] Aiming at the bottleneck problems of the existing medium and low frequency sound-absorbing body, such as bulky, large size, complex structure, and once the sound-absorbing body is prepared, its sound-absorbing performance is difficult to change, it provides a sound-absorbing frequency-adjustable sound-absorbing body based on flexible smart materials. Acoustic body

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