Composite board for low-frequency broadband noise reduction of compartment structure

Abstract

The invention discloses a composite board for low-frequency broadband noise reduction of a compartment structure, and belongs to the technical field of acoustic function materials for noise absorbing.A plurality of sound permeable holes are formed in a perforated plate. The perforated Plate, a local resonance plate and a back plate are arranged in parallel from inside to outside. A plurality of supporting plates are crossed transversely and longitudinally and are fixed between the perforated plate and a base plate of the local resonance plate and between the base plate of the local resonanceplate and the back plate. The base plate is divided by the plurality of supporting plates into a plurality of sound absorbing units. Each sound absorbing unit is internally provided with a film vibrator. Each film vibrator comprises a flexible polymer film and a central mass block. The flexible polymer films are fixedly connected with the base plate. The central mass blocks are attached to the centers of the flexible polymer films. The composite board can be conveniently installed in an engineering environment with strict volume requirements, the noise reduction effect is obvious, the bandwidth of the low-frequency sound absorbing section of the compartment structure can be widened, and low-frequency broadband noise reduction is realized.

Description

technical field [0001] The invention relates to a low-frequency broadband noise-reducing composite panel facing a box structure, and belongs to the technical field of acoustic functional materials for noise absorption. Background technique [0002] The emergence of airplanes, high-speed rail, and automobiles has brought great convenience to our lives, but during the ride, the vibration of the car body structure in the above-mentioned vehicles and the noise in the car body structure have greatly weakened the comfort of passengers. . How to achieve effective vibration and noise reduction in the box structure has always been an urgent problem in the field of engineering technology, and the vibration and noise reduction for low-frequency noise is a difficult point among the difficulties. Through consulting literature, it is found that at this stage for various The method of noise reduction in the car body structure in such vehicles mainly includes vibration reduction of wall pa...

AI Technical Summary

Problems solved by technology

These resistive sound-absorbing materials can usually achieve good sound-absorbing effects above 900Hz, but for the low-frequency range of 0-500Hz, their sound-absorbing effects are very limited.

Sound-absorbing structures such as micro-perforated plates are resonant sound-absorbing structures, and the sound-absorbing frequency can be tuned by changing the size parameters, but this type of material has a narrow sound-absorbing frequency band in the low-frequency range, and the sound-absorbing effect is not good in the low-frequency range

[0005] To sum up, the vibration and noise reduction materials at this stage are not ideal for low-frequency noise suppression. During the normal operation of aircraft, high-speed rail and other vehicles, the vibration generated by the wall plate structure will cause a shock to the passengers in the car. Bring noise pollution, which will have a great impact on the comfort of passengers, so it is urgent to develop a low-frequency vibration and noise reduction material for the car body structure

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