A muffler for receiving exhaust gas from a combustion engine comprises a shell, first and second inlet pipes each having outlets providing exhaust gas to a mixing chamber within the shell, a first chamber and a second chamber positioned within the shell and a pair of communication pipes each including an inlet receiving exhaust gas from the mixing chamber. Each communication pipe includes an outlet providing exhaust to the second chamber. Each of the communication pipes further includes a Helmholtz opening positioned downstream of the mixing chamber. The Helmholtz openings are open to the first chamber.

An acoustic damper includes a low porosity layer section and a housing. The low porosity layer section is formed in a liner of a gas turbine combustor and has an arrangement of elongated generally S-shaped slots formed therein. The housing has a plurality of feed apertures. The housing is coupled to the low porosity layer section thereby defining a cavity such that air outside the housing is configured to flow through the apertures and through the elongated generally S-shaped slots in the low porosity layer section, thereby transforming acoustic energy into thermal energy and aiding in providing an acoustic dampening effect for the gas turbine combustor during operation thereof.

A straddled vehicle having an engine unit supported by a vehicle body frame. The engine unit includes an engine body, a turbocharger, and an exhaust device. The exhaust device includes an exhaust pipe and a muffler that are connected to each other to form a portion of an exhaust passage, to allow the exhaust gas passed through the turbocharger to pass therethrough, and a first catalyst and a second catalyst that are arranged in this order along a direction in which the exhaust gas flows through the exhaust pipe. The exhaust pipe has an upstream end thereof connected to the turbocharger, a downstream end thereof connected to the muffler, and a corner section that is bent in at least a part thereof between a downstream end of the first catalyst and an upstream end of the second catalyst, the catalysts not being arranged in the corner section.

A slip-type active noise control muffler reducing exhaust noise of a vehicle may include at least two guides connected to an inner wall of a housing accommodating exhaust gas in the muffler and formed in a pipe shape in a longitudinal direction of the muffler, and a baffle positioned in a plane shape partitioning the interior of the housing and including an electromagnet on the plane shape to control an interval of the baffles through a movement signal by current applied to the electromagnet according to frequency calculated from the exhaust gas, in which the interval of the baffles may be controlled and the exhaust noise may be reduced by controlling the number of wavelengths depending on the frequency.

An exhaust muffler is made up of a plurality of layers including an exhaust passage pipe and expansion chambers, and includes a front assembly and a rear assembly sub-assembled separately from the front assembly. The front assembly includes a front exhaust passage pipe, a front muffler body disposed in covering relation to the outside of the front exhaust passage pipe and cooperating with the front exhaust passage pipe in making up double-walled pipes, and an exhaust valve disposed in the front exhaust passage pipe. The rear assembly includes a rear exhaust passage pipe and a rear muffler body disposed in covering relation to the outside of the rear exhaust passage pipe and cooperating with the rear exhaust passage pipe in making up double-walled pipes. There is thus provided an exhaust device for an internal combustion engine in which the accuracy of a position where the exhaust valve is installed is high.

Systems, apparatuses, assemblies, and methods for diesel exhaust fluid (DEF) dosing can include a body defining an injector adaptor inlet and an injector adaptor outlet; and an injector mount or interface extending from the body. The injector mount can be between the first and second ends of the injector adaptor. The injector adaptor outlet can define an area greater than an area of the injector adaptor inlet. In a side view of the injector adaptor, at a bottom side of the body, a first straight line can extend along the body from the injector adaptor inlet to the injector adaptor outlet, and at a top side of the body opposite the bottom side, a second straight line can extend along the body from the injector adaptor inlet to the injector adaptor outlet. The second straight line can be at an acute angle relative to the first straight line.

An exhaust system includes a housing comprising a first housing portion and a second housing portion separated by a common wall. The first housing portion has a first exhaust passage therethrough. The first exhaust passage has a first inlet receiving exhaust gasses from a turbocharger. The second housing portion has a second exhaust passage therethrough. The second exhaust passage has a second inlet receiving gasses from an exhaust bypass valve. The first passage and the second passage are non-intersecting within the housing.

A muffler having a movable baffle may include a housing where an input pipe into which exhaust gas is flowed from an engine and an output pipe through which the exhaust gas is expelled to atmosphere are disposed, a baffle which is configured to be slidable along the longitudinal direction of the housing and divides the space of the housing, baffle moving means for moving the baffle to an arbitrary position within a predetermined range along the longitudinal direction of the housing, and a controller which data for determining whether to move the baffle or not is input thereto when the engine is driven, determines whether to move the baffle or not by use of the input data and controls the baffle moving means when the baffle is determined to be moved.

A decomposition chamber for an aftertreatment system includes: a body comprising: an inlet configured to receive exhaust gas, an outlet configured to expel the exhaust gas, a thermal management chamber in fluid communication with the inlet, the thermal management chamber configured to receive an exhaust gas first portion from the inlet, an exhaust assist chamber in fluid communication with the inlet, the exhaust assist chamber configured to receive an exhaust gas second portion from the inlet, and a main flow chamber in fluid communication with the inlet, the main flow chamber configured to receive an exhaust gas third portion from the inlet, receive the exhaust gas first portion from the thermal management chamber, and receive the exhaust gas second portion from the exhaust assist chamber.

An exhaust device includes a casing including an inlet configured to receive an exhaust gas, an outlet configured to discharge the exhaust gas, and a chamber disposed therein between the inlet and the outlet. The casing defines a longitudinal axis along its length. The exhaust device further includes an exhaust conduit at least partially received within the chamber of the casing along the longitudinal axis. The exhaust conduit includes an inner surface, an opposing outer surface, a plurality of perforations extending through the exhaust conduit from the inner surface to the outer surface, and at least one protrusion extending outwardly from the outer surface. The exhaust device further includes an absorptive material disposed on the outer surface of the exhaust conduit. The at least one protrusion of the exhaust conduit engages with the absorptive material in order to form an interference fit between the absorptive material and the exhaust conduit.