KOCHETOV ACOUSTIC ABSORBER FOR NOISE SILENCERS OF COMPRESSOR STATIONS Russian patent published in 2016 - IPC F01N1/04 

FIELD: acoustics; instrumentation.

SUBSTANCE: sound absorber is designed for damping noise of compressor stations and test boxes for gas turbine engines. Sound absorber comprises a cylindrical frame in form of perforated sleeve and cover, filled with sound absorber, and outside bushing there is a layer of acoustically transparent cover, and frame comprises cover with circular collars for fixing the cylindrical bushing, covers are central rod with hooks on both ends, and cylindrical sleeve consists of two perforated shells, inner and outer, space between which is filled with sound absorbing element outside perforated cylindrical bushing there is a layer of acoustically transparent shell, wherein sound-absorbing material placed in inner cavity of sound absorber is made of unwinding roll, one end of which is rigidly fixed on central rod, and free end rests against inner shell to form in cross-section perpendicular to rod, a closed shape in form of Archimedean spiral with increasing from centre to periphery air gaps, wherein it has higher porosity in comparison to sound absorber located inside shells and covers have outer surfaces of fairings conical shape, and sound-absorbing element comprises perforated walls, between which there are layers of sound reflecting and sound-absorbing materials of different density arranged in two layers, wherein layers of sound reflecting material are made from complex profile composed of evenly distributed hollow tetrahedrons, which enable to reflect sound waves incident in all directions and which are located respectively at perforated walls, and layers of sound reflecting material are made from heat-insulating material, wherein sound-absorbing element over its entire surface is lined with acoustically transparent material.

EFFECT: high efficiency of soundproofing at high frequencies.

1 cl, 2 dwg