An SCR system includes at least one catalyst, and an intake conduit. The intake conduit includes an intake conduit first sidewall, at least a portion of which defines a first curvature. An intake conduit second sidewall is coupled to the intake conduit first sidewall so as to define the intake conduit. A catalyst is fluidly coupled to the intake conduit through the intake conduit second sidewall. The intake conduit second sidewall is inclined at a first angle with respect to a longitudinal axis of the SCR system, such that an intake conduit second end cross-section of the intake conduit is smaller than an intake conduit first end cross-section. An intake conduit third sidewall is positioned at the intake conduit second end. The intake conduit is structured to produce an even flow split of the exhaust gas through the intake conduit internal volume towards the catalyst.

An insert assembly unit for a muffler of an exhaust system of an internal combustion engine includes two walls (12, 14) arranged at spaced locations from one another. Each of the two walls has a circumferential edge area (20, 22) configured for fixing at a circumferential wall of a muffler. An exhaust gas flow unit (26) is arranged between the two walls. The exhaust gas flow unit includes a flow duct area (34) with an exhaust gas outer flow opening (38) to be positioned directed towards an opening in a circumferential wall of a muffler, a first mounting duct area (40) with a first mounting opening (44) for fixing the exhaust gas flow unit at a first wall of the walls, and a second mounting duct area (42) with a second mounting opening (46) for fixing the exhaust gas flow unit at a second wall of the walls.

A fluid-cooled manifold is configured to cool exhaust from an engine. The fluid-cooled manifold includes a plurality of exhaust runners. Each of the exhaust runners includes a runner body having an inlet end and an outlet end, an exhaust conduit extending through the runner body, and a coolant passage extending through the runner body. The fluid-cooled manifold also includes an exhaust collection manifold including a plurality of inlets. Each inlet of the exhaust collection manifold is coupled to the exhaust outlet opening of a respective one of the exhaust runners. The fluid-cooled manifold also includes a coolant feed pipe and a coolant exit pipe. The coolant feed pipe includes a plurality of outlets coupled to the coolant inlets of the exhaust runners. Likewise, the coolant exit pipe includes a plurality of inlets coupled to the coolant outlets of the exhaust runners.

An exhaust system for a vehicle having an internal combustion engine includes an exhaust pipe having a central axis and configured to receive an exhaust gas flow from the engine, a catalytic converter disposed within the exhaust pipe, and an exhaust gas burner assembly having a burner unit configured to generate and supply a heated burner flow to a supply pipe. An outlet end of the supply pipe is disposed within the exhaust pipe and extends substantially parallel to the exhaust pipe central axis such that the exhaust gas flows around the supply pipe outlet end. A plurality of mixing apertures are formed in the supply pipe outlet end and configured to promote mixing of the heated burner flow and the exhaust gas flow to disperse heat over the catalytic converter for rapid heating thereof.

A sinuous balanced mid-pipe exhaust system has a straight mid-pipe and a sinuous mid-pipe disposed intermediate manifold and muffler. The manifold has a differential bilateral manifold pipe length. The longer manifold pipe connected to the straight mid-pipe and the shorter manifold pipe connected to the sinuous mid-pipe. Sinuous mid-pipe has 2-3 sinusoidal curved segments such that a sinuous gas flow path therethrough substantially equals the straight pipe flow path length and the manifold differential pipe length. The method balances and equalizes gas flows by defining straight gas flow path, having a path length and defining a sinuous gas flow path with at least two sinusoidal segments which is equal to the path length and the differential path length.

Mixer box for mixing, vaporization and decomposition of a liquid additive to the exhaust gas flow from a combustion engine, comprising a gas inlet (108), a gas outlet (109) and internal duct means establishing a gas flow path (A-H, a-h) from the gas inlet (108) to the gas outlet (109). The duct means includes a first duct portion (107) having an outer wall (171) and an inner wall (161), which is surrounded by the outer wall (171), such that the gas flow path through said first duct portion (107) is established inbetween. The first duct portion (107) is provided with at least two partitions (121-124) extending between the outer wall (171) and the inner wall (161), which separate the first duct portion (107) into at least two duct sections (101a, 101b, 102a, 102b) of which at least one is an upstream duct section (101a, 101b) and at least one is a downstream duct section (102a, 102b).

An SCR system includes at least one catalyst, and an intake conduit. The intake conduit includes an intake conduit first sidewall, at least a portion of which defines a first curvature. An intake conduit second sidewall is coupled to the intake conduit first sidewall so as to define the intake conduit. A catalyst is fluidly coupled to the intake conduit through the intake conduit second sidewall. The intake conduit second sidewall is inclined at a first angle with respect to a longitudinal axis of the SCR system, such that an intake conduit second end cross-section of the intake conduit is smaller than an intake conduit first end cross-section. An intake conduit third sidewall is positioned at the intake conduit second end. The intake conduit is structured to produce an even flow split of the exhaust gas through the intake conduit internal volume towards the catalyst.

A multi-mode muffler for an exhaust system of an internal combustion engine provides a rotary plate that modulates exhaust gas flow between a first and second flow path. Each flow path may provide different sound dampening characteristics, thereby providing different sound profiles with the same muffler. In a disclosed embodiment, the rotary plate is driven by a shaft coupled to an external actuator. Also, a third possible position of the rotary plate may allow flow through both the first and second flow paths, thereby providing a third possible noise profile. One of the sound profiles may be louder than the other thereby allowing the muffler to switch between “loud” and “quiet” modes of operation.

A sound suppressor for use in firearms, internal combustion engines, and numerous other sound-generating devices includes a structure having a plurality of ports, openings, or orifices which function as whistles and which suppress sound from a source of the sound using destructive interference. A combination of varying distances between components is configured for delaying the wave from one port or whistle to the next, so that the whistles are partially out of phase with respect to time, and placing the orifices of the whistles a certain distance apart to compensate for the remaining phase difference in order to create the desired destructive interference.

Methods and systems are provided for an exhaust muffler system with multiple inlets of different diameters. In one example, the muffler system may include multiple sets of inlet pipes to a muffler with each set of inlet pipes including pipes of different diameters with valves controlling exhaust flow into the inlet pipes. Exhaust from an engine bank may flow to a distinct set of inlet pipes and a distinct outlet pipe of the muffler via a separate exhaust passage.