Noise abatement system for internal combustion engines

A noise abatement system for internal combustion engines suitable for generating inside of each of a plurality of expansion chamber destructive acoustic interference of sound waves, said system including:

• a containment body equipped with an inlet hole for the entry of exhaust gases from an internal combustion engine, a plurality of expansion chambers placed in sequence and separated by parallel dividing partitions, each equipped with a through-hole for the passage of gases placing in fluid communication two neighboring expansion chambers;
• said expansion chambers having two opposing through-holes, one as gas inlet and one as gas outlet;
• a device which has a rotating turbine equipped with at least one blade, housed in a first expansion chamber, on which impact the gases coming from the engine, entering the containment body, and to convey the gases towards a first dividing partition of the first expansion chamber and a second expansion chamber with the consequent increase in the speed of the gas flow and a decrease in pressure, the noise abatement system being characterized in that a rotating shaft is integrated in said rotating turbine extending from said rotating turbine body, along an axis comprising the center of gravity of the expansion chambers up to an opposite end of the containment body, said rotating shaft having placed around said axis and on said shaft rotary fins which open and close the through-holes between expansion chambers alternately and successively, generating a swirling movement of the flow of gas entering each expansion chamber,
• wherein the fins are placed on the said turbine shaft in such a way that by rotating they open and close the present holes alternately in the dividing partitions and said alternate mode it is able to close the outlet hole for each expansion chamber in sequence leaving the entrance hole open allowing the portion of gas present inside the expansion chamber to perform a rotary or vortex movement and of colliding with the gas entering from the previous expansion chamber said meeting between the portion of gas entering and the portion of gas which effects the rotary movement determines a phase opposition of the sound waves and consequent destructive acoustic interference.