KOCHETOV SOUND-ABSORBING ELEMENT Russian patent published in 2016 - IPC E04B1/84 

FIELD: acoustics.

SUBSTANCE: invention relates to industrial acoustics. This is achieved due to that in sound absorbing element, comprising a smooth and perforated surface between which a multilayer sound absorbing structure, which is made in two layers: sound-reflecting layer adjoining rigid wall, and sound-absorbing layer adjoining perforated wall, layer of sound reflecting material is made from complex profile composed of evenly distributed hollow tetrahedrons, which enable to reflect sound waves incident in all directions, and perforated wall has following perforation parameters: hole diameter - 3÷7 mm, perforation percentage 10%÷15%, wherein holes can be made in form of circular, triangular, square, rectangular or rhomboid, wherein in case of non-circular holes nominal diameter should be considered maximum diameter of circle inscribed in polygon, and sound-absorbing material used is mineral wool on basalt base Rockwool or URSA mineral wool, or basalt wool or P-75, or glass wool lined with glass felt, or foamed polymer, for example polyethylene or polypropylene, surface of fibrous sound absorbers is treated with special porous paints, permeable to air (for example, Acutex T), or coated with air-permeable fabrics or nonwoven materials, for example Lutrasil.

EFFECT: technical result is high efficiency of noise absorption and reliability of structure overall.

2 cl, 2 dwg