The aftertreatment device has a casing (10), which has an inlet opening (12) for the inflow of the exhaust gas, an outlet opening (14) for the outflow of the exhaust gas and a feed hole (16) for dispensing reactive substance to the casing. The reactive substance can be for example fuel, ammonium or urea/water solution. As an extension of the outlet opening there is a mixing tube (18) directed outwards from the casing for mixing the exhaust gas and the reactive substance. Inside the casing there is a feeding channel (20) for guiding the exhaust gas to the mixing tube. The feeding channel has an open first end extending to the outlet opening, the cross-sectional area of which first end is smaller than the cross-sectional area of the outlet opening. The wall (22) of the feeding channel has holes (24) for the inflow of the exhaust gas. Preferably, the wall of the feeding channel has at least along a part of its length a conical shape. The second end of the feeding channel can be connected to the end wall of the casing, whereby the exhaust gas can flow into the feeding channel only through the holes in the wall of the feeding channel. The exhaust gas can flow to the mixing tube through the feeding channel as well as through the annular slot around the first end of the feeding channel. The exhaust gas flowing through the feeding channel forms a center flow to the mixing tube and the exhaust gas flowing through the slot surrounding the feeding channel forms an edge flow surrounding and rotating around the center flow.

An exhaust-gas mixing pipe for admixing additive into an exhaust-gas stream of a combustion engine. The housing wall has multiple rows, arranged over a circumference U, of openings through which gas can flow into the interior of the pipe, wherein the at least one opening of a row forms in each case one stage M characterized according to its size by the average opening cross section Q of the openings, wherein the sum of all the opening cross sections Q of all the openings of all the rows of the exhaust-gas mixing pipe is equal to SQ. In that context, at least one first-order stage M1, is provided, wherein stage M1 has openings having an average opening cross section Q1. At least one second-order stage M2, is provided, with openings having an average opening cross section Q2, where Q2>=f Q1, where 5<=f<=25.

Systems are provided for a mixer configured to be used in either an intake or exhaust passage. In one example, a mixer in the intake passage may be adapted to mix EGR with intake air and a mixer in the exhaust passage may be adapted to mix urea with exhaust gas.

A flow device for an exhaust system includes a body that defines an interior cavity. An exhaust inlet passage is disposed in the interior cavity. An exhaust outlet passage is disposed in the interior cavity so that at least a portion of the exhaust inlet passage circumferentially surrounds at least a portion of the exhaust outlet passage. A doser is adapted to inject reductants into the interior cavity of the body such that the reductants are injected in the same general direction as the direction of flow of the exhaust gases.

An embodiment of a mixing assembly for mixing at least two fluids, comprises a housing and an injector body disposed concentrically therein, a vorticing element disposed about the injector body, and a compression element disposed about an outlet of the injector body. The housing is disposed for passage of a first fluid therethrough. The injector body being disposed within the housing and further disposed for the introduction of a second fluid within the flow path of the first fluid.

A mix box for an exhaust system of an internal combustion engine, the mix box being used to incorporate additives into an exhaust gas flow and including at least one inlet tube, at least one outlet tube and a housing for accommodating the inlet tube and the outlet tube, wherein: the housing delimits a volume of the mix box in relation to the surroundings; the inlet tube has an inflow section located inside the housing, which inflow section is provided with at least one inflow opening for introducing the exhaust gas into the housing; the outlet tube has a metering device designed as an injection nozzle at the end of the outlet tube and has an outflow section located inside the housing, which outflow section has a length (La) and is provided with at least one outflow opening for discharging the exhaust gas from the housing; a flow zone is provided between the inlet tube and the outlet tube and the flow zone, over at least 30% of its length (La), is free of flow guiding elements which deflect the flow in a circumferential direction and which have an outer face and an inner face inside the volume.

A mixing device for integrating into an exhaust pipe of an internal combustion engine and for intermixing an exhaust gas flow T, which device is formed by a housing including a pipe wall for guiding the exhaust gas in a main flow direction H, an intermediate wall which at least partially delimits a flow cross section Qs of the housing, and by a mixing pipe, wherein: the mixing pipe has an injection nozzle for an additive to be incorporated, the nozzle being in the region of a first end E1 of the mixing pipe, and the mixing pipe is accommodated, in the region of a second end E2, in the intermediate wall; a perforation zone having a through-flow cross section Qp is provided at least between the injection nozzle and the intermediate wall; the intermediate wall and the mixing pipe 5 separate the housing into an inflow sector and an outflow sector; at least 90% of the gas to be guided from the inflow sector to the outflow sector can be directed through the perforation zone; a wedge-shaped flow-directing element having a directing nose is provided after the mixing pipe, which nose protrudes beyond the pipe wall and/or the intermediate wall and by means of which the exhaust gas flow T can be divided into two partial flows T1, T2; and wherein the partial flows T1, T2 can be brought into a counter swirl flow in relation to the main flow direction H.

A mixer for a vehicle exhaust system includes a mixer housing that defines an interior cavity for engine exhaust gases, and which includes a doser opening formed within a wall of the mixer housing. A cone has a cone inlet opening aligned with the doser opening and a cone outlet into the interior cavity. A cylindrical member surrounds at least a portion of the cone and includes at least one window opening. At least one diverter duct is fixed to the mixer housing and has a first duct end open to the interior cavity and a second duct end at least partially overlapping the at least one window opening such that a portion of the engine exhaust gases in the interior cavity is directed to enter the first duct end, flow through the at least one window and then flow into the cone inlet opening to be mixed with a fluid injected through the doser opening.

A mixer assembly for mixing an injected reductant with an exhaust gas output from a combustion engine comprises a mixer housing including a wall defining an exhaust passageway having a longitudinal axis. A tubular swirling device housing extends along a first axis substantially transverse to the longitudinal axis. The tubular swirling device includes a plurality of openings through which exhaust gas enters. The exhaust gas within the tubular swirling device swirls about the first axis and exits at an outlet end of the tubular swirling device. A mixing plate is positioned immediately downstream of the tubular swirling device and includes apertures through which the exhaust gas exiting the outlet end of the tubular swirling device flows. The mixing plate swirls the exhaust about a second axis extending parallel to the longitudinal axis.

According to one embodiment, an apparatus (50) for mounting to an inner wall (33) of an exhaust tube (32) includes a tube engagement surface (52) and an exhaust engagement surface (54A). The tube engagement surface comprises a convex surface of a constant first radius of curvature about a first axis. The exhaust engagement surface is adjacent the tube engagement surface, and includes a concave surface of a second radius of curvature about a second axis generally perpendicular to the first axis.