Patent ID: 7310939

Claim:
A device for reducing the jet noise of a turbomachine, said turbomachine having a longitudinal axis (X-X) and a substantially cylindrical nozzle ( 10 ) extending along said longitudinal axis of the turbomachine, having a downstream end for mixing the flows of gas inside and outside said nozzle, said device comprising a plurality of corrugations ( 26 ) disposed to extend the downstream end of the nozzle, and a plurality of notches disposed between pairs of successive corrugations in said plurality of corrugations, wherein each corrugation is asymmetrical relative to a radial plane that is median to said corrugation and each notch is asymmetrical relative to a radial plane that is median to said notch and said plurality of corrugations and said plurality of notches are symmetrical relative to at least one axis perpendicular to said longitudinal axis of the turbomachine so as to generate a dual counter-rotating effect between said gas flows.