GAS FLOW NOISE SUPPRESSOR Russian patent published in 2017 - IPC F01N1/00 

FIELD: machine engineering.

SUBSTANCE: suppressor includes the housing with the inlet and outlet pipe branches, the hollow insert with the throttling element, mounted coaxially with the housing, made of the porous noise absorbing material and the coil spring, faced with sound absorbing material and located between the insert and the housing, and forming the screw channel, associated with the inlet pipe branch. The turns of the cylindrical screw spring in its axial section are made in the form of the rigid and perforated walls, between which there are two layers: the sound-reflecting layer, adjacent to the rigid wall, and the sound-absorbing layer, adjacent to the perforated wall. The sound reflecting material layer is made of the complex profile, consisting of the evenly distributed hollow tetrahedra.

EFFECT: noise suppression efficiency improvement.

3 dwg