Space sound absorption body:

A sound absorbing component which is dispersed and suspended above the building space to reduce indoor noise or improve indoor sound quality. The space acoustic absorber has the characteristics of less materials, light weight, low investment, high sound absorption efficiency, flexible layout and convenient construction.

Compared with the sound absorbing material on the indoor surface, the space absorber has higher sound absorption efficiency under the same projection area. This is because the space sound absorption body has a greater effective sound absorption area (including the upper top surface of the space sound absorption body, the lower bottom surface and the side). In addition, as the sound waves reflect many times between the top surface of the sound absorption body and the top of the building, it is absorbed many times, increasing the sound absorption and raising the sound absorption efficiency. Generally speaking, the improvement of sound absorption efficiency is most significant in the middle and high frequency sections.

The sound absorption performance of space absorbers is usually expressed by the effective sound absorption of a single absorber at different frequencies. The effect of sound absorption (or reducing reverberation time) of space sound absorption body depends mainly on the number of space sound absorption body, suspension distance and material and structure, and also related to the sound field conditions in the building space. For example, the original indoor surface sound absorption is very small, the reflection sound is more and the reverberation time is very long, then the noise reduction effect of the suspended space sound absorption body is usually 5~8 decibels and up to 10~12 dB at the highest level.

Material and structure

The common space sound absorbing body is made up of skeleton, protective coating and sound absorption fillers. The choice of materials should be based on the size, stiffness and decoration requirements of the space absorber. The framework can be made of wood, angle steel and thin-walled steel. The face protection layer can use plastic window, plastic net, wire mesh and various plates (such as thin steel plate, aluminum plate, plastic plate etc.) perforated plate, its thickness is 0.5 to 1 millimeter, aperture is 4~8 millimeter, perforation rate should be more than 20%. The sound-absorbing filler usually uses ultra fine glass cotton to outsource the fiberglass cloth. The filling density is 25~30 kg / m, and the thickness should be selected in the range of 5~10 centimeters according to the spectrum characteristics of the sound source. Decorative material ornaments also have great influence on sound absorption coefficient of sound absorption body. It is necessary to choose proper finishing treatment according to the requirements of use, and make a comprehensive analysis on the effect of building decoration to avoid unnecessary waste.

The experimental results show that the sound absorption coefficient decreases with the increase of the surface area of the square cone, four prism, six prism, conical, and round platform, and the high frequency is more obvious for the same surface area. When the surface area is equal, the sound absorption effect of cone and frustum absorber is the best. Increasing the number of side sides of the sound absorption body increases the sound absorption of the sound absorption body, and the sound absorption coefficient of the outer cone, four prism, six prism and the sound absorption body of the round platform increases with the increase of the volume of the cavity. When the base area is equal, the sound absorption coefficient of the frequency of the square cone and the four prism absorber increases with the increase of the cavity volume.