SYMMETRICAL SOUND-ABSORBING ELEMENT Russian patent published in 2018 - IPC E04B1/84 G10K11/16 

FIELD: acoustics.

SUBSTANCE: invention relates to the industrial acoustics. Technical result is achieved by the fact that the symmetrical sound-absorbing element is made in the form of two identical structures of sound-absorbing elements located symmetrically with respect to the vibration-damping layer placed between the rigid walls, each of the identical structures of sound-absorbing elements contains a smooth and perforated surface, between which there is a multi-layer sound-absorbing structure in the form of a rigid and perforated walls, between which there are two layers: sound-reflecting layer adjacent to a rigid wall, and adjacent to the perforated wall sound-absorbing layer, wherein the sound-reflecting material layer is made with a complex shape consisting of uniformly distributed hollow tetrahedra, allowing to reflect the incident in all directions sound waves, as a sound-absorbing material, mineral wool is used on a basalt basis of the Rockwool type, or mineral wool of the URSA type, or basalt wool of the P-75 type, or glass wool with a fiberglass cladding or foamed polymer, the surface of fibrous sound absorbers is treated with special porous paints that let in air, or is covered with breathable fabrics or non-woven materials, material based on aluminum-containing alloys is used as a sound reflecting material, followed by filling them with titanium hydride or air with a density of 0.5…0.9 kg/m³ with the following strength properties: compressive strength within 5…10 MPa, flexural strength within 10…20 MPa, or sound-proof plates on the basis of glass staple fiber of Shumostop type with a material density equal to 60÷80 kg/m³, 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