Local resonance acoustic black hole structure

A local resonance and acoustic technology, applied in the direction of sound-producing equipment, instruments, etc., can solve the problems of reducing the frequency of action, the low-frequency black hole effect is difficult to achieve, etc., and achieve the effect of easy adjustment.

Active Publication Date: 2016-10-12
NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The cut-off frequency is often affected by the size of the ABH, and the low-frequency black hole effect is difficult to achieve in applications where the size of the ABH is limited, so it is urgent to reduce the frequency of action by effective means

Method used

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  • Local resonance acoustic black hole structure
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  • Local resonance acoustic black hole structure

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Embodiment Construction

[0021] The local resonance acoustic black hole structure of the present invention includes a plate structure 1 and an acoustic black hole structure 2 connected to the plate structure 1, wherein the distance between the front and rear surfaces of the plate structure 1 is fixed from right to left, and the distance between the upper and lower surfaces of the plate structure 1 It is also fixed from right to left. The distance between the front and back surfaces of the acoustic black hole structure 2 is fixed from right to left, and the distance between the upper and lower surfaces of the acoustic black hole structure 2 is from right to left in the exponential function form h(x)=ex m (the exponent m is not less than 2) decreases gradually, and the distance between the upper and lower surfaces of the rightmost end of the acoustic black hole structure 2 is equal to the distance between the upper and lower surfaces of the plate structure 1. A local vibrator 4 is connected to the leftm...

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Abstract

The invention discloses a plate or bridge structure of a local resonance acoustic black hole (ABH). The local resonance acoustic black hole structure comprises an acoustic black hole region (a region which is gradually thinned), a local vibrator (such as a mass spring unit) and an acoustic black hole extension part. According to the local resonance acoustic black hole structure disclosed by the invention, the local vibrator is constituted by units having the properties of a spring vibrator, so that an effective action frequency range of an acoustic black hole effect is reduced, and subsequently, a vibration control effect of the acoustic black hole structure is effectively improved. The local resonance acoustic black hole structure disclosed by the invention has a broad application prospect in vibration absorption and noise reduction of structures.

Description

Technical field: [0001] The invention relates to a local resonance acoustic black hole structure, which belongs to the technical field of structural vibration reduction and noise reduction. Background technique: [0002] The acoustic black hole (ABH) effect is actually a wave trap made by changing the structural form. Through the change of the structural impedance, the phase velocity and group velocity of the wave propagating in the structure are changed, and the wave aggregation is realized in the local area of ​​the structure. The main way to change the structural impedance to achieve the acoustic black hole effect is to change the thickness of the structure. Utilizing the propagation characteristics of bending waves in variable thickness structures, when the thickness of the structure decreases according to a certain power function, the phase velocity and group velocity of bending waves also decrease correspondingly. Ideally, when the thickness is reduced to zero, the wa...

Claims

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Application Information

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Patent Type & Authority Applications(China)
IPC IPC(8): G10K11/172
CPCG10K11/172
Inventor 季宏丽裘进浩黄薇成利
Owner NANJING UNIV OF AERONAUTICS & ASTRONAUTICS
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