space sound absorber

A type of sound-absorbing component that is dispersed and suspended in the upper part of building space to reduce indoor noise or improve indoor sound quality. Space sound absorbers have the characteristics of using fewer materials, being lightweight, saving investment, having high sound absorption efficiency, flexible layout, and convenient construction. Many countries have

Space absorbers have been in use since the 1950s, and their application gradually became widespread in the 1970s. China has been using it since the 1970s. In the 1980s, applications were increasing day by day. Space absorbers are designed based on the building's usage characteristics, area, floor height, structural form, and installation

Decorative requirements and sound source characteristics can come in various shapes such as plate, block, cylinder, cone, and sphere. Among them, the plate-like structure is the simplest and most commonly used. Space absorbers are commonly used in indoor sports arenas, with various shapes and arrangements

The formula can enhance the indoor decorative effect, and most importantly, its sound absorption performance can prevent echo defects in large halls and effectively reduce reverberation time.

principle

Compared with sound-absorbing materials on indoor surfaces, spatial sound-absorbing bodies have higher sound absorption efficiency under the same projection area. This is because spatial absorbers have a larger effective absorption area (including the top and bottom surfaces of the spatial absorbers)

Face and side); In addition, due to the multiple reflections of sound waves between the upper surface of the sound absorber and the top surface of the building, they are absorbed multiple times, increasing the sound absorption amount and improving the sound absorption efficiency. The improvement in sound absorption efficiency is usually most significant in the mid to high frequency range.

The sound absorption performance of spatial sound absorbers is often represented by the effective absorption capacity of individual sound absorbers at different frequencies. The effectiveness of sound absorption and noise reduction (or reduction of reverberation time) of spatial sound absorbers mainly depends on the number of spatial sound absorbers, suspension spacing, materials, and structure

It is also related to the sound field conditions within the building space. If the original indoor surface has little sound absorption, more reflected sound, and a long reverberation time, the noise reduction effect of hanging spatial sound absorbers is often 5-8 decibels, and can reach up to 10-12 decibels at its highest; As shown in the original indoor table

If the surface absorption is large and the reverberation process is not obvious, there is no need to hang a spatial sound absorber.

design

Mainly consider the following three factors.

material and structure

The common spatial sound-absorbing body consists of a skeleton, a protective layer, and sound-absorbing fillers. The selection of materials should depend on the size, stiffness, and decoration requirements of the spatial sound absorbing body. The skeleton can be made of wood, angle steel, thin-walled steel, etc. The protective layer can be made of plastic window screen, plastic

Perforated plates made of material mesh, steel wire mesh, and various types of plates (such as thin steel plates, aluminum plates, plastic plates, etc.) should have a thickness of 0.5-1.0 millimeters, a hole diameter of 4-8 millimeters, and a perforation rate greater than 20%. The sound-absorbing filler is usually made of ultra-fine glass wool wrapped in glass fiber cloth,

The filling density can be taken as 25-30 kg/m3, and the thickness should be selected within the range of 5-10 cm according to the spectral characteristics of the sound source.

Hanging quantity

The number of suspended spatial sound absorbers should be calculated and determined based on their sound absorption characteristics and the amount of sound absorption required to reduce indoor noise (or control reverberation time). When designing with plate-shaped spatial sound absorbers, if the total area of the sound absorbers is equivalent to that of the building

30-40% of the top area of the object can achieve the optimal absorption efficiency of the plate-shaped spatial sound absorber. In practical engineering, in order to meet the requirements of reducing noise or controlling reverberation time, the total area of spatial sound absorbers should be 40-50% of the building's roof area; like

Increasing the number of spatial sound absorbers will actually affect the overall sound absorption performance of the spatial sound absorbers, resulting in a waste of funds.

hang

Most spatial sound absorbers are hung at the top of building spaces, and are mostly suspended from the top. Plate shaped spatial sound absorbers can be horizontally dispersed and hung, vertically dispersed and hung, or horizontally and vertically composite hung. With the same total area, the noise reduction effect can be achieved

The fruits are basically the same. The height above the ceiling of a horizontally suspended plate-shaped spatial sound absorber is generally about 1/5 to 1/7 of the net height of the room. Generally speaking, considering the difficulty of construction, the spatial sound absorber is suspended below the steel frame at the top of the building, and its height will be exactly at

About 1/5 to 1/7 of the net height of the room, meeting the requirements for sound absorption and decoration; If conditions permit, it can be hung lower and closer to the sound source. In order to improve the architectural decoration effect of suspended space absorbers, the form, color, and hanging method of the spatial absorbers should be considered

Comprehensively consider factors such as formula. If the spatial sound absorbing body is suspended in a certain artistic pattern and coordinated with lighting, illumination, ventilation, and architectural decoration, the overall effect will be better.

application

Widely applicable to indoor sports halls, factories with excessive noise, as well as broadcasting stations, television recording studios, studios, schools, theaters, libraries, cultural centers, auditoriums, multipurpose halls, conference rooms, and music halls with high sound quality requirements

The place.