MULTI-SECTION NOISE SUPPRESSOR Russian patent published in 2018 - IPC F01N1/04 

FIELD: acoustics.

SUBSTANCE: invention relates to compressor stations and test boxes noise suppression equipment for gas turbine engines. Muffler contains a cylindrical base, rigidly connected to the end inlet and outlet nozzles, rigidly connected to the central partitions having perforation, on base levelling grid is arranged connected to adapter, on which a sound-absorbing unit consisting of separate series-connected sections is fixed, each of which is made with sound-absorbing lining "a", and the section consists of four subsections with a characteristic size "c", in which there are single sound absorbers with a certain step "b", single sound absorbers are made in the form of a perforated sleeve and covers, the bushing consists of two perforated shells – external and internal, the space between them is filled with a sound-absorbing element containing perforated walls, between which are layers of sound-reflecting, as well as sound-absorbing materials of different densities, and the central layer of the sound-reflecting material of the complex profile is made with a perforation in the form of uniformly distributed hollow tetrahedra, allowing to reflect the sound waves falling in all directions, and the perforation acoustically connects it with the sound-absorbing layers symmetrically adjacent to it from sound-absorbing materials of different densities, the perforation is made in the form of the Helmholtz resonator cavities, the volume of which is the space enclosed between the surfaces of the sound-absorbing layers and the central layer of the complex profile.

EFFECT: higher efficiency of noise suppression.

1 cl, 4 dwg