US Patent 7934581 Broadband noise resonator

An apparatus comprising includes a conduit portion having a conduit inner surface and a conduit outer surface, and a plurality of chambers in fluid communication with the conduit portion. The chambers include a first chamber defined, at least in part, by a first outer housing and a first chamber volume. The first chamber is in fluid communication with the conduit portion. A fluid is permitted to flow between the conduit portion and the first chamber through a first flow area. The chambers also include a second chamber defined, at least in part, by a second outer housing and a second chamber volume. The second chamber is in fluid communication with the conduit portion. A fluid is permitted to flow between the conduit portion and the second chamber through a second flow area. The first chamber volume is generally equal to the second chamber volume and the first flow area is greater than the second flow area. The chambers further include a third chamber defined, at least in part, by a third outer housing and a third chamber volume. The third chamber is in fluid communication with the conduit portion. A fluid is permitted to flow between the conduit portion and the third chamber through a third flow area, wherein the first chamber volume is greater than the third chamber volume.