Abstract: A resonator for an induction system includes an inlet and outlet with a resonator cavity arranged therebetween. A tube is arranged within the resonator cavity and at least partially extends between the inlet and outlet. In one example, at least one supplemental noise attenuation device is in communication with the arcuate tube, such as a quarter wave tube and/or Helmholtz resonator. A large opening is provided in the tube that opens into the resonator cavity. In one example, the large opening is arranged on an outer radius side and faces a large cavity portion of the resonator cavity. Additional supplemental noise attenuation is provided by a collar arranged concentrically relative to the tube providing an annular quarter wave tube that is coaxial with the direction of flow from the outlet.

Abstract: The invention relates to a Helmholtz resonator (6) for damping airborne sound in a space, particularly in a conduit (4, 5) transporting airborne sound, comprising a housing (8) surrounding a resonance volume (9), comprising at least one neck (10) for connecting the resonance volume (9) to the space or to the conduit (4, 5) transporting the airborne sound. The Helmholtz resonator (6) obtains at least two resonance frequencies if the housing (8) has at least one wall section delimiting the resonance volume (9), said wall section being formed by a vibratory membrane (11), and if the membrane (11) is tuned such that the resonance frequency thereof corresponds to the first order of the resonance frequency of an identically constructed Helmholtz resonator that does not have such a membrane (11).

Abstract: An air induction silencer assembly includes an acoustic interference member disposed within a conduit. The acoustic interference member is tuned to acoustically cancel a selected noise energy frequency. An acoustic absorbing member is also disposed within the conduit. The acoustic absorbing member converts noise energy within the conduit into heat energy to attenuate noise energy within the air induction silencer assembly. The air induction silencer assembly connects to a flexible conduit that includes an inlet portion, an outlet portion, and a flexible joint that connects the inlet portion and the outlet portion together. The flexible joint includes a rolling lobe and a rolling surface. The rolling lobe moves along the rolling surface when the inlet portion moves relative to the outlet portion.

Abstract: A resonator for an induction system includes an inlet and outlet with a resonator cavity arranged therebetween. A tube is arranged within the resonator cavity and at least partially extends between the inlet and outlet. In one example, at least one supplemental noise attenuation device is in communication with the arcuate tube, such as a quarter wave tube and/or Helmholtz resonator. A large opening is provided in the tube that opens into the resonator cavity. In one example, the large opening is arranged on an outer radius side and faces a large cavity portion of the resonator cavity. Additional supplemental noise attenuation is provided by a collar arranged concentrically relative to the tube providing an annular quarter wave tube that is coaxial with the direction of flow from the outlet.

Abstract: A duct for an induction system is provided that has an effective length between an inlet and outlet. An aperture is provided a wall of the duct at a location corresponding to a pipe resonance for attenuating noise at the pipe resonance frequency. In one example, the aperture is provided using a cluster of holes arranged at the location. Multiple apertures are arranged about a circumference of the duct, for example, at opposing sides of the duct. In one example, an aperture is provided at a distance of approximately one quarter the effective length from both the inlet and the outlet. A porous non-woven structure is arranged over the aperture to minimize pressure losses associated with the aperture.