Three-dimensional multi-cavity micro-perforated periodical ultra-wideband sound-absorbing structure

Abstract

The invention relates to a three-dimensional multi-cavity micro-perforated periodical ultra-wideband sound-absorbing structure, comprising a micro-perforated panel, parallel-arrangement cross sectionsin periodical structure, parallel-arrangement vertical sections in periodical structure and a unit bottom plate are connected to form two, preferably three or four, closed cavities periodically arranged in two orthogonal directions, having maxium depth that is 1.5-5 times as great as minimum depth; the micro-perforated panel is provided with micropores having an area that is 0.2-5% of that of themicro-perforated panel, the micropores are 0.2-1.2 mm in pore diameter, with unit width and length not exceeding 0.15 m. The three-dimensional multi-cavity micro-perforated periodical ultra-widebandsound-absorbing structure is just fixed to a wall in the place requiring sound absorption. The three-dimensional multi-cavity micro-perforated periodical ultra-wideband sound-absorbing structure is simple, is convenient to process, is thin and portable and has good sound-absorbing property, low-frequency sound absorption coefficient is not lower than 0.8, the peak value reaches 1.0, the sound absorption is flat, and the structure is widely applicable, is easy to wash and tolerant to high temperatures, has excellent weatherability and is suitable for complete recycling.

Description

technical field [0001] The invention belongs to the technical field of acoustics, in particular to a three-dimensional multi-cavity micro-perforated periodic ultra-wide-band sound absorption structure for broadband noise reduction, the surface is flush, and the ultra-wide sound absorption frequency band is provided. Background technique [0002] With the development of urban economy and population growth, the problem of noise pollution is becoming more and more serious. Complaints about the impact of noise pollution on people account for more than 50% of all environmental complaints in economically developed cities. On the other hand, with the advancement of urbanization construction, the increasing social activities and the use of equipment make people's living environment have obvious low-frequency characteristics, which often causes people to subjectively feel that the sound pressure level of environmental noise has not yet reached the standard limit. trouble. Low-freque...

AI Technical Summary

Problems solved by technology

[0005] However, for ordinary resonant sound-absorbing structures with a single cavity, in order to have good sound-absorbing performance at low frequencies, the depth of the cavity must be greatly increased, and the volume is often large

In addition, the common resonant sound-absorbing structure with a single cavity has a narrow sound-absorbing frequency band. For a micro-perforated plate with a pore size of 1 mm, the half-sound-absorbing bandwidth (sound absorption coefficient ≥ 0.5) is usually less than 2 octaves

The lower the sound-absorbing frequency requirement, the greater the thickness of the sound-absorbing structure. In situations where the space is generally limited, ordinary resonant sound-absorbing structures cannot well meet the actual needs of noise control.

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