A heat exchange and noise reduction panel the panel for an aircraft comprising: an external surface intended to be swept by an airflow and from which fins extend along a first and a second main predetermined direction; cavities forming Helmholtz resonators, linked to the first ends of channels for the passage of air, the second ends of which communicate with said airflow, such that said channels form necks, referred to as Helmholtz resonators, extending substantially along the first direction; and at least one oil flow chamber extending between said external surface and said at least one cavity, and intended to discharge the thermal energy carried by the oil, characterized in that wherein said channels are formed, at least in part, inside said fins.

A vehicle exhaust system includes a tubular component having an inner surface and an outer surface such that the inner surface defines a primary exhaust gas flow path and wherein the tubular component extends along a central axis from an inlet end to an outlet end. The tubular component comprises at least one ridge along the central axis. The at least one ridge extends at least partly along a circumference of the tubular component. Each ridge includes a first portion angularly devoid of apertures and extending inwardly from the tubular component and a second portion disposed downstream of the first portion. The second portion is angularly devoid of apertures and extends inwardly from the tubular component. The tubular component also includes a plurality of spaced apertures positioned along a portion of the circumference of the tubular component and downsteam of the second portion.

A disposing method for an inlet pipe in a muffler that includes an outer shell, an inlet pipe, and a separating plate, the disposing method comprising: a first step of inserting the inlet pipe into the outer shell from an opening at one end of the outer shell; a second step of disposing the inlet pipe by moving the inlet pipe within the outer shell in a direction substantially orthogonal to the direction of insertion of the inlet pipe; and a third step of disposing the separating plate by inserting the separating plate into the outer shell from the opening at the other end of the outer shell.

A disposing method for an inlet pipe in a muffler that includes an outer shell, an inlet pipe, and a separating plate, the disposing method comprising: a first step of inserting the inlet pipe into the outer shell from an opening at one end of the outer shell; a second step of disposing the inlet pipe by moving the inlet pipe within the outer shell in a direction substantially orthogonal to the direction of insertion of the inlet pipe; and a third step of disposing the separating plate by inserting the separating plate into the outer shell from the opening at the other end of the outer shell.

An air exhausting device includes a muffler internally divided into a plurality of chambers by a separator, an inlet pipe that couples an exhaust pipe of an engine to the muffler, and an outlet pipe that is a path to discharge an exhaust gas inside the muffler to outside air. The muffler is configured of an expansion chamber to which a downstream end of the inlet pipe opens, and a resonator chamber communicated with only the expansion chamber via a plurality of resonator pipes. Any of or both of lengths and thicknesses of the plurality of resonator pipes are different.

An air exhausting device includes a muffler internally divided into a plurality of chambers by a separator, an inlet pipe that couples an exhaust pipe of an engine to the muffler, and an outlet pipe that is a path to discharge an exhaust gas inside the muffler to outside air. The muffler is configured of an expansion chamber to which a downstream end of the inlet pipe opens, and a resonator chamber communicated with only the expansion chamber via a plurality of resonator pipes. Any of or both of lengths and thicknesses of the plurality of resonator pipes are different.

Provided acoustic devices include an external housing defining an expansion chamber and a wall extending through and partitioning the expansion chamber into a central chamber and a peripheral chamber adjacent the central chamber, wherein an inlet and outlet communicate with the central chamber, and wherein the wall includes a plurality of apertures formed therethrough to allow air movement to and from the central and expansion chambers, the plurality of apertures sized to provide an average flow resistance ranging from 100 MKS Rayls to 5000 MKS Rayls. The acoustic devices advantageously show significant sound attenuation while streamlining air flow to reduce pressure drop across the expansion chamber.

A vehicle exhaust system component includes an exhaust tube defining an exhaust gas flow path, a side branch tuning tube connected to the exhaust tube at an interface, and a porous structure associated with the exhaust tube to reduce noise generated at the interface. In one example, the porous structure comprises a perforated orifice in the exhaust tube. In another example, the porous structure comprises a mesh screen or mesh sleeve.

Waveguide or flow guide surfaces can improve the efficiency of fluid flow through tubes or over surfaces. When incorporated in a tube, the waveguides improve flow and function as sound absorbers making them useful in engine mufflers, firearm silencer/suppressors and jet engine exhaust attenuators. On surfaces, the waveguides can reduce fluid drag and find use on projectiles (e.g., bullets), airfoils for aircraft, and land borne vehicles. The waveguide array in either a tubular chamber or on a surface comprises a plurality of successive wave-like undulations inclined generally in the direction of flow and when employed in tubes extending inwardly to permit an unobstructed path for the fluid gas from entry to exit. The waves define annular wave cavities between their successive inwardly extending edges and the wall of the chamber with each cavity having a cavity mouth open to the unobstructed path. The waveguides are sized and spaced so that gas vortices are created within the cavities when gas flow occurs which vortices create a fluid boundary layer that assists the gas flow.

An air cleaner of this disclosure includes a hollow case, a filter element, and an opening end member. The hollow case defines an expanded space; the filter element defines an upstream-side expanded space and a downstream-side expanded space in the expanded space; the case includes an intake port configured to bring an upstream-side duct into communication with the upstream-side expanded space; the opening end member is formed from a material having an air permeability in a range of 0.3 to 100 sec/300 cc, and is integrated on an inner side of the intake port so as to project into the upstream-side expanded space and so as to extend a duct wall of the intake port; and D representing a diameter of the opening end member and L representing a length thereof satisfy 0.25D≦L≦2.0D.