SOUND ABSORBING ELEMENT Russian patent published in 2018 - IPC E04B1/84 

FIELD: physics.

SUBSTANCE: invention relates to industrial acoustics. Technical result is achieved by the fact that the sound-absorbing element comprises smooth and perforated surfaces between which there is a multilayer sound-absorbing structure in the form of rigid and perforated walls, between which there are two layers: a sound-reflecting layer adjacent to the rigid wall, and sound-absorbing layer, adjacent to the perforated wall, wherein the sound reflecting material layer is made from a complex profile consisting of evenly distributed hollow tetrahedrons, allowing to reflect sound waves incident in all directions, and the perforated wall has the following perforation parameters: holes diameter - 3÷7 mm, perforation percentage 10%÷15%, and the shape of the apertures can be made in the form of apertures of a circular, triangular, square, rectangular or diamond-shaped profile, wherein in case of non-circular apertures, the maximum diameter of circle inscribed into a polygon shall be considered as a nominal diameter, and as a sound-absorbing material, a mineral wool on a basalt basis is used, while the surface of fibrous absorbers is treated with special porous paints that let the air, or is covered with air-permeable fabrics or non-woven materials, herewith the sound-reflecting layer adjacent to the rigid wall is made with a perforation from the sound-reflecting material of the complex profile consisting of evenly distributed hollow tetrahedrons allowing to reflect sound waves incident in all directions, while the perforation on the sound-reflecting layer is performed by analogy with the orifice holes, which are the mouth of Helmholtz resonators, the capacity of which is determined by the volume of the sound-reflecting layer and the rigid wall of the sound-absorbing element adjacent to it.

EFFECT: technical result is an increase in the efficiency of sound deadening and reliability of the structure in whole.

1 cl, 1 dwg