Reducing agent mixer

The present disclosure relates to mixing devices included in automotive exhaust treatment systems. More particularly, the present disclosure relates to reducing agent mixers for mixing reducing agents with exhaust streams to induce a chemical reaction between the reducing agent and exhaust gasses to reduce Nitrous Oxides (NOx) in the exhaust gas. Reducing agent mixers in accordance with the present disclosure include reducing agent delivery devices for conducting reducing agents into an internal mixing space through which exhaust gasses flow.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a U.S. national counterpart application of international application serial No. PCT/US2016/058114, filed Oct. 21, 2016 the disclosure of which is incorporated by reference in its entirety.

BACKGROUND

The present disclosure relates to exhaust treatment systems for automotive applications, and particularly to mixing devices included in exhaust treatment systems. More particularly, the present disclosure relates to mixers for injecting reducing agents, such as urea solutions, into exhaust streams to induce a chemical reaction between the reducing agent and exhaust gasses to reduce Nitrous Oxides (NOx) in the exhaust gas.

SUMMARY

A reducing agent mixer adapted for inclusion in an exhaust treatment system is disclosed in this paper. The reducing agent mixer is configured to mix a reducing agent, for example a urea solution, with exhaust gas moving through the exhaust treatment system to cause a chemical reaction and reduce Nitrous Oxides (NOx) in the exhaust gas.

In illustrative embodiments, the reducing agent mixer includes a mixing can and a doser. The mixing can defines an internal space that houses the exhaust gas and reducing agent during mixing. The doser is mounted outside the mixing can and discharges predetermined amounts of reducing agent from a storage container associated with the exhaust treatment system into the mixing can.

In illustrative embodiments, the reducing agent mixer includes a reducing agent delivery device that holds the doser in position outside the mixing can and conducts the reducing agent from the doser through an injection cone into the internal space defined by the mixing can. The reducing agent delivery device uses exhaust gas to encourage distribution of reducing agent as it moves into the mixing can. Exhaust gas is also used by the reducing agent delivery device to block buildup of reducing agent on the injection cone that might hinder distribution of the reducing agent into the mixing can.

In illustrative embodiments, the reducing agent delivery device includes a doser attachment, the injection cone, and an exhaust guide. The doser attachment is coupled to the doser outside the mixing can and extends through an outer wall of the mixing can into the internal space. The injection cone is arranged inside the doser attachment and carries reducing agent from the doser and some exhaust gas into the internal space of the mixing can. The exhaust guide collects exhaust gas moving into the reducing agent mixer and distributes the exhaust gas around the injection cone before it enters the injection cone to be mixed with reducing agent. By distributing exhaust gas around the injection cone, exhaust gas enters the injection cone and lines an internal surface of the injection cone to block build up of reducing agent on an internal surface of the mixing cone.

In illustrative embodiments, the exhaust guide includes an exhaust-distribution duct that extends upstream from the injection cone and forms an exhaust-receipt opening. The exhaust-receipt opening faces in the upstream direction and is aligned with a single guide aperture formed in the mixing can. Accordingly exhaust moving through the guide aperture enters the exhaust-distribution duct to be carried around the inlet aperture of the injection cone.

In illustrative embodiments, the exhaust guide includes a plurality of flow distribution walls that divide the exhaust-distribution duct into a plurality of flow tubes. Each of the flow tubes is shaped to discharge exhaust gas at a different location around the inlet aperture of the injection cone. By discharging at different locations around the injection cone, exhaust gas is distributed around the inlet aperture of the injection cone.

In illustrative embodiments, the doser attachment includes a coupler flange outside the mixing can coupled to the doser, a mount cylinder that extends into the mixing can, and a port plate that extends over the mount cylinder. The injector cone includes an outer dome and a flared wall that extends from the outer dome away from the doser attachment. The port plate has a flat shape and is formed to include an injection port that the doser discharges reducing agent through. The outer dome of the injector cone has a dome shape and forms the inlet aperture aligned with the injector port to receive reducing agent moving through the port plate.

DETAILED DESCRIPTION

A reducing agent mixer16included in an exhaust treatment system12for a vehicle10is shown inFIGS. 1-4. Reducing agent mixer16mixes a reducing agent (illustratively a urea solution) with exhaust gas moving through the reducing agent mixer so that the reducing agent chemically reacts with the exhaust gas and reduces undesired Nitrous Oxides (NOx) produced when fuel is burned. Reducing agent mixer16includes a mixing can18into which exhaust gasses flow and a doser20that injects predetermined amounts of reducing agent into mixing can18.

Reducing agent delivery devices22,222, shown inFIGS. 5 and 10, are adapted to be included in reducing agent mixer16. Reducing agent delivery devices22,222conduct reducing agent13from doser20into mixing can18through injection cones26,226using exhaust gas14to encourage entry and distribution of reducing agent as shown inFIGS. 7 and 12. Exhaust gas14is also used by reducing agent delivery devices22,222to line an interior surface25,225of injection cones26,226blocking buildup of reducing agent13on injection cones26,226that might hinder distribution of reducing agent as it moves into mixing can18.

Each reducing agent delivery devices22,222includes an integrated exhaust guide28,228that receives and distributes exhaust gas14around injection cones26,226as shown inFIGS. 8 and 13. Exhaust guide28, shown inFIGS. 5-7, includes an exhaust-distribution duct48and flow-distribution walls50,52, and54that divide exhaust-distribution duct48into multiple flow tubes60,62,64. Each flow tube60,62,64delivers exhaust to different locations around injection cone26as suggested inFIG. 8. Exhaust guide228, shown inFIGS. 10-12, includes an undivided exhaust-distribution duct248. Exhaust guide228is shaped to deliver exhaust around injection cone226as suggested inFIG. 13. Exhaust guide228may include flow-distribution directors250and252(shown in phantom) that encourage flow to be distributed to different locations around injection cone226.

Vehicle10includes an engine11an exhaust treatment system12as shown, for example, inFIG. 1. Engine11is, illustratively, an internal combustion engine configured to combust fuel and discharge an exhaust stream14. Exhaust treatment system12receives exhaust stream14produced by vehicle10and is configured to reduce various effluents before exhaust stream14is released to atmosphere15. Exhaust treatment system12includes a reducing agent mixer16for injecting and mixing a reducing agent13, illustratively a urea solution, into exhaust stream14as shown in

Reducing agent mixer16includes a mixing can18, a doser20, and a reducing agent delivery device22as shown inFIG. 2. Mixing can18provides an internal space19for mixing reducing agent13with exhaust stream14allowing chemical reactin of exhaust stream14with reducing agent13to reduce NOxin exhaust stream14as shown inFIG. 3. Doser20injects reducing agent13into internal space19in a controlled fashion to achieve a desired reaction with exhaust stream14. Reducing agent delivery device22supports doser20outside mixing can18and conducts reducing agent13into internal space19of mixing can18. Reducing agent delivery device22is shaped to utilize exhaust stream14to distribute reducing agent13in internal space19of mixing can18and to block deposition or buildup of reducing agent13on components of reducing agent delivery device22as suggested inFIG. 7.

Mixing can18extends along a central axis18A and is configured to induce a swirling motion onto exhaust stream14moving into reducing agent mixer16. Mixing can18includes an outer wall30, an upstream baffle32, a downstream baffle34, and an inner wall36within outer wall30and between upstream baffle32and downstream baffle34as shown inFIG. 4. Outer wall30is formed to include a can aperture31to allow reducing agent delivery device22to extend into internal space19while doser20remains outside of mixing can18. Upstream baffle32is shaped to induce a swirl into exhaust stream14and includes a guide aperture33through which reducing agent delivery device22receives a portion of exhaust stream14as shown inFIG. 3. Downstream baffle34conducts mixed exhaust stream14and reducing agent13out of reducing agent mixer16into other components of exhaust treatment system12as shown inFIG. 9. Inner wall36lies within outer wall30and is configured to separate upstream baffle32and downstream baffle34to establish internal space19. Inner wall36is also configured to be heated by exhaust stream14to maintain a higher temperature than outer wall30of mixing can18in order to prevent a buildup of reducing agent13on inner wall36within internal space19after reducing agent13is injected into internal space19.

Upstream baffle32provides an inlet for exhaust stream14as it moves into internal space19defined by mixing can18as suggested inFIGS. 3 and 4. Upstream baffle32includes a rim70and a panel72as shown inFIG. 4. Rim70extends from panel72along a portion of outer wall30included in mixing can18and provides means for coupling upstream baffle32to outer wall30. Panel72closes an upstream end of outer wall30and is formed to include openings to admit exhaust stream14into internal space19of mixing can18.

Panel72is illustratively contoured and includes a first section74arranged to extend in a plane generally perpendicular to central axis18A and a second section76arranged to extend in a plane generally parallel to central axis18A as shown inFIG. 3. First section74is formed to include exhaust inlet apertures77in various locations and at least a portion of first section74is contoured into a helical shape to induce swirl into exhaust stream14. Second section76is formed to include a swirl aperture78generally parallel to central axis18A that allows exhaust stream14to enter internal space19moving circumferentially around central axis18to induce swirl into exhaust stream14. Guide aperture33through which exhaust gas flows into reducing agent deliver device22is formed through portions of both first section74and the second section76of panel72included in upstream baffle32as shown inFIGS. 3 and 4.

Downstream baffle34provides an outlet for exhaust stream14as it moves out of internal space19defined by mixing can18as suggested inFIG. 4. Downstream baffle34includes a rim80and a panel82as shown inFIG. 4. Rim80extends from panel82along a portion of outer wall30included in mixing can18and provides means for coupling downstream baffle34to outer wall30. Panel82closes a downstream end of outer wall30and is formed to include openings87to discharge exhaust stream14from internal space19of mixing can18.

Doser20injects reducing agent13into mixing can18in amounts designed to cause desired chemical reactions with exhaust stream14. Doser20is electronically controlled and can adjust the amount of reducing agent injected based on parameters associated with engine11, exhaust stream14, and other suitable factors.

Reducing agent delivery device22is coupled to outer wall30of mixing can18and conducts reducing agent13from doser20into mixing can18as shown inFIG. 3. Reducing agent delivery device22includes a doser attachment24, an injection cone26, and an exhaust guide28as shown inFIG. 5. Doser attachment24closes aperture31in outer wall30of mixing can18and fixes doser20in place relative to mixing can18as shown inFIG. 7. Injection cone26is arranged to receive reducing agent13from doser20and a portion of exhaust stream14from exhaust guide28to distribute reducing agent13in mixing can18. Exhaust guide28is arranged to receive a portion17of exhaust stream14from upstream of injection cone26and direct portion17of exhaust stream14into injection cone26aas shown inFIG. 7. Portion17of exhaust stream14blocks the deposition or buildup of reducing agent on injector cone26.

Doser attachment24supports doser20relative to mixing can18and provides an injection port39so that reducing agent13discharged by doser20is carried through doser attachment24and can aperture31into mixing can18as shown inFIG. 7. Doser attachment24includes a mount cap38, a closure flange40, and a mount cylinder42as shown inFIG. 5. Mount cap38couples to doser20via fasteners (not shown) and forms an injection port39so that doser20can inject reducing agent13into internal space19. Closure flange40rests against outer wall30of mixing can18to close can aperture31when reducing agent delivery device22is assembled within reducing mixer18. Mount cylinder42extends from mount cap38, through closure flange40and can aperture31into mixing can18as shown inFIG. 7.

Injection cone26facilitates distribution of reducing agent13as it moves into internal space19of mixing can18by conducting reducing agent13through an expanding distribution channel27defined by injection cone26as shown inFIG. 7. Injection cone26is spaced apart from mount cap38of reducing agent delivery device22and is encircled by mount cylinder42of reducing agent delivery device22to create a gap G supplied with exhaust stream14by exhaust guide28as shown inFIG. 7. Injection cone26includes an outer dome44and a flared wall46that extends from outer dome44as shown inFIG. 5. Outer dome44has a dome shape and is formed to include an inlet aperture45. Inlet aperture45is aligned with injection port39to receive reducing agent13and is surrounded by gap G to receive portion17of exhaust stream14as shown inFIG. 7. Flared wall46has a hollow, frustoconical shape that flares outward as it extends from outer dome44. Flared wall46defines an outlet aperture47though which reducing agent13and portion17of exhaust stream14exit expanding mixing channel27into internal space19of mixing can18as shown inFIG. 7.

Flow ports61,63, and65are configures to provide ingress means for admitting all exhaust flow that moves into reducing agent delivery device22to be discharged out of injection cone26. In the illustrative embodiment, during operation, all exhaust flow into reducing agent delivery device22is discharged out of injection cone26and flow ports61,63, and65are only inlets for exhaust.

Flow distribution walls50,52, and54extend from floor56to inlet opening45of injection cone26as shown inFIG. 5. Flow distribution walls50,52, and54also extend from inlet opening45to mount cylinder42within gap G. In this way, flow distribution walls50,52, and54separate exhaust-distribution duct48into a first flow tube60, a second flow tube62, and a third flow tube64as shown inFIGS. 5 and 8. Flow distribution walls50,52, and54are spaced circumferentially around inlet opening45of inlet dome44about 120 degrees from each other so that each flow tube60,62, and64provides exhaust to a different location around injection cone16. However, it is within the scope of this disclosure to vary the spacing between each individual flow distribution wall50,52, and54.

Flow distribution wall50separates flow tubes60and62and includes sides501and502that face in opposite directions within exhaust-distribution duct48as shown inFIG. 8. Flow distribution wall52separates flow tubes62and64and includes sides521and522that face in opposite directions within exhaust-distribution duct48. Flow distribution wall54separates flow tubes60and64and includes sides541and542that face in opposite directions within exhaust-distribution duct48. Sides502and521face towards one another within exhaust-distribution duct48. Sides501and522face toward side wall58within exhaust distribution conduit48.

Mount cap38includes a flat surface37that forms the upper boundary of gap G and is spaced apart from injection cone26to define gap G therebetween. Flat surface37of mount cap38is arranged perpendicular to a central axis42A of mount cylinder42and parallel to a plane defined by inlet aperture45. Flow tubes60,62,64, injection cone26, mount cap38, and mount cylinder42cooperate to direct exhaust toward inlet aperture45of injector cone26as shown inFIG. 7. Flow tubes60,62, and64conduct exhaust toward injection cone26. Outer dome44of injector cone26and mount cylinder42direct exhaust toward flat surface37while flat surface37directs exhaust toward inlet aperture45. At the same time, doser20injects reducing agent13into reducing agent delivery device22through injection port39and toward inlet aperture45. Exhaust is consolidated within gap G from flow tubes60,62, and64and combined with the injected reducing agent13. Both reducing agent13and exhaust are then forced into inlet aperture45of injection cone26at a substantially even distribution, blocking buildup or deposition of reducing agent13along injection cone26.

As exhaust enters flow port61, it is confined within flow tube60by ceiling55, floor56, side wall58and side501as shown inFIG. 8. Flow tube60then directs portion17circumferentially around injection cone26where exhaust is then blocked by side542of flow distribution wall54. Exhaust is then directed along injection cone26and enters inlet opening45through a first vent100formed in inlet opening45as shown inFIG. 8.

As exhaust enters flow port63, it is confined within flow tube62by ceiling55, floor56, and sides502and521as shown inFIG. 8. Flow tube62then directs exhaust along injection cone26and into inlet opening45through a second vent102formed in inlet opening45as shown inFIG. 8.

As exhaust enters flow port65, it is confined within flow tube64by ceiling55, floor56, side wall58and side522as shown inFIG. 8. Flow tube64then directs exhaust circumferentially around injection cone26where exhaust is then blocked by side541of flow distribution wall54. Exhaust is then directed along injection cone26and enters inlet opening45through a third vent104formed in inlet opening45as shown inFIG. 8.

In one embodiment, reducing agent delivery device22is separated into a first cast section90and a second cast section92as shown, for example, inFIG. 6. First cast section90includes doser attachment24and ceiling55of exhaust guide28. Second cast section92includes injector cone26and floor56and side wall58of exhaust guide28. Second cast section92also forms flow distribution walls50,52,54. First cast section90and second cast section92are bonded together to form agent deliver device22. In other embodiments, reducing agent delivery device22may be a monolithic cast component in which all features are integrally formed with one another as suggested inFIG. 5. In other embodiments, reducing agent delivery device22may be a multi-piece assembly.

In illustrative embodiments, a weld95bonds first cast section90and second cast section92. In other embodiments other bonding features or fasteners may couple first cast section90and second cast section92. Separating reducing agent delivery device22into first and second cast sections90,92facilitates casting of internal features.

As shown inFIG. 9, reducing agent mixer16is adapted to fit within exhaust treatment system12. Exhaust treatment system12illustratively includes a diesel oxidation catalyst900(DOC), a diesel particulate filter902(DPF), a selective catalytic converter904(SCR), and other catalyst devices such as an ammonia oxidation catalyst906(AMOX) in addition to reducing agent mixer16.

In operation, exhaust stream14flows from engine11of vehicle10(not shown) through diesel oxidation catalyst900(DOC) and diesel particulate filter902(DPF). Exhaust stream14then flows to reducing agent mixer16where doser20injects reducing agent13into reducing agent delivery device22to be added to exhaust stream14and mixed to create a mixture914of exhaust stream14and reducing agent13. Mixture914then flows through selective catalytic converter904(SCR) and ammonia oxidation catalyst906(AMOX) for reduction of nitrous oxides, hydrocarbons, and other impurities through chemical reactions. Exhaust stream14is then released into atmosphere15.

In a second embodiment, shown inFIG. 10, a reducing agent delivery device222is similar to reducing agent delivery device22fromFIG. 5. Reducing agent delivery device222includes a doser attachment224, an injection cone226, and an exhaust guide228.

Doser attachment224closes aperture31in outer wall30of mixing can18and fixes doser20in place relative to mixing can18as shown inFIG. 12. Doser attachment224includes a mount cap238that forms an injection port239, a closure flange240that rest along mixing can18when reducing agent delivery device222is assembled within mixing can18, and a mount cylinder242attached to closure flange240and extends from mount cap238through mixing can18as shown inFIG. 12.

Injection cone226is arranged to receive reducing agent213from doser20and a portion17of exhaust stream14from exhaust guide228to distribute reducing agent213in mixing can18as shown inFIG. 12. Injection cone226includes an outer dome244formed to include an inlet aperture245and a flared wall246that extends from outer dome244and is formed to include an outlet aperture247as shown inFIG. 12.

Exhaust guide228includes an exhaust-distribution duct248that is arranged to face upstream and receive a portion17of exhaust stream14through an exhaust-receipt opening229as shown inFIG. 12. Exhaust-distribution duct248and mount cylinder242form a gap2G that surrounds injection cone226and allow distribution of exhaust around injection cone226and into injection aperture245. Exhaust guide228also includes a plurality of optional flow-distribution walls250and252indicated by dashed lines inFIGS. 10 and 13. Flow-distributions walls250and252separate exhaust-distribution duct248so that portion17of exhaust stream14is distributed around injection cone26as shown inFIG. 13.

Optional flow-distribution directors250and252extend from injection cone226along floor256to a point within exhaust-distribution duct248to encourage flow to be distributed to different locations around injection cone226as suggested inFIG. 10. Flow distribution directors250and252do not extend all the way to exhaust-receipt opening229. In some embodiments, other suitable flow directors such as bumps, troughs, and surface discontinuities may be included to encourage flow to be distributed to different locations around injection cone226.

In one embodiment, reducing agent delivery device222is separated into a first cast section290and a second cast section292as shown, for example, inFIG. 11. First cast section290includes doser attachment224and ceiling255of exhaust guide228. Second cast section292includes injector cone226and floor256and side wall258of exhaust guide228. Second cast section292also includes optional flow distribution directors250,252. First cast section290and second cast section292are bonded together to form agent deliver device222. In other embodiments, reducing agent delivery device222may be a monolithic cast component in which all features are integrally formed with one another as suggested inFIG. 10. In other embodiments, reducing agent delivery device222may be a multi-piece assembly.

In illustrative embodiments, a weld295bonds first cast section290and second cast section292. In other embodiments other bonding features or fasteners may couple first cast section290and second cast section292. Separating reducing agent delivery device222into first and second cast sections290,292facilitates casting of internal features.

The following numbered clauses include embodiments that are contemplated and non-limiting:

Clause 1: A reducing agent mixer adapted for use in an exhaust treatment system associated with an internal combustion engine, the reducing agent mixer comprising

a mixing can arranged around a central axis and shaped to define an internal space, the internal space adapted to house mixing of exhaust gas and reducing agent when exhaust gas moves along the central axis in a downstream direction through the reducing agent mixer,

a doser mounted outside the mixing can and configured to discharge predetermined amounts of reducing agent into the internal space of the mixing can, and

a reducing agent delivery device including a doser attachment that supports the doser outside the internal space of the mixing can, an injection cone that conducts reducing agent discharged from the doser into the internal space of the mixing can, and an exhaust guide configured to provide means for collecting exhaust gas moving into the reducing agent mixer and for distributing the exhaust gas around an inlet aperture of the injection cone so that exhaust gas moving through the injection cone lines an internal surface of the injection cone and blocks deposition of reducing agent onto an internal surface of the mixing cone.

Clause 2: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the mixing can includes an outer wall formed to include a can aperture through which the reducing agent delivery device extends, an upstream baffle that defines an upstream side of the internal space and formed to include guide aperture, and a downstream baffle that defines a downstream side of the internal space, the exhaust guide includes an exhaust-distribution duct that extends in the upstream direction from the injection cone and forms an exhaust-receipt opening that opens facing in the upstream direction and that is aligned with the guide aperture so that exhaust moving through the guide aperture enters the exhaust guide for distribution around the inlet aperture of the injection cone when exhaust gas flows through the reducing agent mixer.

Clause 3: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein exhaust guide includes a plurality of flow distribution walls that divide the exhaust-distribution duct into a plurality of flow tubes and each of the flow tubes is shaped to discharge exhaust gas at a different location around the injection cone so that exhaust gas is distributed around the inlet aperture of the injection cone when exhaust gas flows through the reducing agent mixer.

Clause 4: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the exhaust-distribution duct terminates downstream of the guide aperture formed in the upstream baffle such that the reducing agent delivery device is spaced apart from the upstream baffle and some exhaust gas moving through the guide aperture does not enter the exhaust-distribution duct when exhaust gas flows through the reducing agent mixer.

Clause 5: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the exhaust-distribution duct extends through guide aperture of the upstream baffle and terminates upstream of the guide aperture.

Clause 6: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the plurality of flow distribution walls divide the exhaust receipt opening into a plurality of flow ports each aligned with the guide aperture formed in the upstream baffle so that exhaust moving through the guide aperture enters the exhaust guide for distribution around the inlet aperture of the injection cone when exhaust gas flows through the reducing agent mixer.

Clause 7: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the upstream baffle includes a first section arranged to extend in a plane generally perpendicular to the central axis and a second section arranged to extend in a plane generally parallel to the central axis, and the guide aperture formed in the upstream baffle is formed through portions of both the first section and the second section of the upstream baffle.

Clause 8: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the doser attachment of the reducing agent delivery device includes a mount cap outside the mixing can that is coupled to the doser and a mount cylinder that extends through the can aperture formed in the outer wall of the mixing can, the mount cylinder encircling at least a portion of the injection cone to define a gap therebetween, and the gap is in fluid communication with the exhaust guide.

Clause 9: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the mount cap includes a coupler flange configured to be coupled to the doser by fasteners and a port plate that extends over the mount cylinder outside the mixing can to close an outer end of the mount cylinder, the port plate formed to include an injection port aligned with the inlet aperture of the injection cone to allow reducing agent discharged from the doser to move through the mount cap and into the injection cone, and the port plate having a substantially flat shape across the outer end of the mount cylinder.

Clause 10: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein exhaust guide includes a plurality of flow distribution walls that divide the exhaust-distribution duct into a plurality of flow tubes and each of the flow tubes is shaped to discharge exhaust gas at a different location around the inlet aperture of the injection cone so that exhaust gas is distributed around the injection cone when exhaust gas flows through the reducing agent mixer.

Clause 11: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the plurality of flow distribution walls extend into the gap between the mount cylinder and the injection cone.

Clause 12: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the injector cone includes an outer dome that forms the inlet aperture of the injector cone and a flared wall that forms an outlet aperture of the injector cone, the outer dome has a dome shape, and the flared wall has a hollow frusto-conical shape that extends from the outer dome.

Clause 13: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the doser attachment of the reducing agent delivery device includes a mount cap outside the mixing can that is coupled to the doser and a mount cylinder that extends through the can aperture formed in the outer wall of the mixing can, the mount cylinder encircling the outer dome of the injection cone at least a portion of the flared wall of the injection cone to define a gap therebetween, and the gap is in fluid communication with the exhaust guide.

Clause 14: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the mount cap includes a coupler flange configured to be coupled to the doser by fasteners and a port plate that extends over the mount cylinder outside the mixing can to close an outer end of the mount cylinder, the port plate formed to include an injection port aligned with the inlet aperture of the injection cone to allow reducing agent discharged from the doser to move through the mount cap and into the injection cone, and the port plate having a substantially flat shape across the outer end of the mount cylinder.

Clause 15: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein exhaust guide includes an exhaust-distribution duct that extends from the mount cylinder and a plurality of flow distribution walls that divide the exhaust-distribution duct into a plurality of flow tubes, each of the flow tubes is shaped to discharge exhaust gas at a different location around the injection cone, and the plurality of flow distribution walls extend into the gap between the mount cylinder and the injection cone so that exhaust gas is distributed around the inlet aperture of the injection cone when exhaust gas flows through the reducing agent mixer.

Clause 16: A reducing agent mixer adapted for use in an exhaust treatment system associated with an internal combustion engine, the reducing agent mixer comprising

a mixing can arranged around a central axis and shaped to define an internal space, the mixing can including an outer wall formed to include a can aperture and an upstream baffle formed to include guide aperture, and

a reducing agent delivery device including a doser attachment configured to support a doser outside the internal space of the mixing can in a position to discharge reducing agent through the can aperture, an injection cone configured to conduct reducing agent discharged from a doser outside the mixing can into the internal space of the mixing can, and an exhaust guide including an exhaust-distribution duct spaced apart from the outer wall of the mixing can, wherein the exhaust-distribution duct forms an exhaust-receipt opening aligned with the guide aperture so that exhaust from the guide aperture enters the exhaust-distribution duct when exhaust gas flows through the reducing agent mixer and the exhaust-distribution duct is shaped to extend from the exhaust-receipt opening toward and around the injection cone so as to distribute exhaust gas to all sides of the injection cone when exhaust gas flows through the reducing agent mixer.

Clause 17: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein exhaust guide includes a plurality of flow distribution walls that divide the exhaust-distribution duct into a plurality of flow tubes and each of the flow tubes is shaped to discharge exhaust gas at a different location around the inlet aperture of the injection cone.

Clause 18: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the exhaust-distribution duct terminates before it reaches the upstream baffle such that the reducing agent delivery device is spaced apart from the upstream baffle.

Clause 19: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the exhaust-distribution duct extends through guide aperture of the upstream baffle and the exhaust-receipt opening is spaced from the guide opening in upstream baffle.

Clause 20: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the plurality of flow distribution walls divide the exhaust receipt opening into a plurality of flow ports each aligned with the guide aperture formed in the upstream baffle so that exhaust moving through the guide aperture is divided by the flow distribution walls when exhaust gas flows through the reducing agent mixer.

Clause 21: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the upstream baffle includes a first section arranged to extend in a plane generally perpendicular to the central axis and a second section arranged to extend in a plane generally parallel to the central axis, and the guide aperture formed in the upstream baffle is formed through portions of both the first section and the second section of the upstream baffle.

Clause 22: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the doser attachment of the reducing agent delivery device includes a mount cap outside the mixing can and a mount cylinder that extends through the can aperture formed in the outer wall of the mixing can, the mount cylinder encircling at least a portion of the injection cone to define a gap therebetween, and the gap is in fluid communication with the exhaust-distribution duct.

Clause 23: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the mount cap includes a coupler flange configured to be coupled to the doser by fasteners and a port plate that extends over the mount cylinder outside the mixing can to close an outer end of the mount cylinder, the port plate formed to include an injection port aligned with the inlet aperture of the injection cone to allow reducing agent discharged from the doser to move through the mount cap and into the injection cone, and the port plate having a substantially flat shape across the outer end of the mount cylinder.

Clause 24: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein exhaust guide includes a plurality of flow distribution walls that divide the exhaust-distribution duct into a plurality of flow tubes, each of the flow tubes is shaped to discharge exhaust gas at a different location around the injection cone, and the plurality of flow distribution walls extend into the gap between the mount cylinder and the injection cone so that exhaust gas is distributed around the inlet aperture of the injection cone when exhaust gas flows through the reducing agent mixer.

Clause 25: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the reducing agent delivery device comprises a first cast section and a second cast section coupled to the first cast section; the first cast section forms the mount cap of the doser attachment, the mount cylinder of the doser attachment, and a portion of the exhaust distribution duct are formed by the first cast section; and the second cast section forms the injection cone and a portion of the exhaust distribution duct.

Clause 26: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein exhaust guide includes a plurality of flow distribution walls that divide the exhaust-distribution duct into a plurality of flow tubes, the plurality of flow distribution walls extend into the gap between the mount cylinder and the injection cone, and the second cast section forms the flow distribution walls.

Clause 27. A reducing agent mixer adapted for use in an exhaust treatment system associated with an internal combustion engine, the reducing agent mixer comprising

a mixing can arranged around a central axis and shaped to define an internal space, and

a reducing agent delivery device including a doser attachment configured to support a doser outside the internal space of the mixing can and an injection cone configured to conduct reducing agent discharged from a doser into the internal space of the mixing can, wherein the doser attachment includes a coupler flange outside the mixing can coupled to the doser, a mount cylinder that extends into the mixing can and encircles a portion of the injection cone, and a port plate having a flat shape that extends over the mount cylinder outside the mixing can and formed to include an injection port, and wherein the injector cone includes an outer dome that forms the inlet aperture aligned with the injector port of the port plate and a flared wall that forms an outlet aperture of the injector cone.

Clause 28: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the injection port and the inlet aperture are spaced apart from one another and the injection port is smaller than the inlet aperture.

Clause 29: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the mount cylinder encircles the outer dome of the injection cone and a portion of the flared wall of the injection cone to define a gap therebetween.

Clause 30: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the reducing agent delivery device includes an exhaust guide that extends around another portion of the flared wall of the injection cone and is configured to collect and distribute exhaust gas around the injection cone when exhaust gas flows through the reducing agent mixer.

Clause 31: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein exhaust guide includes an exhaust-distribution duct that extends from the mount cylinder and a plurality of flow distribution walls that divide the exhaust-distribution duct into a plurality of flow tubes, each of the flow tubes is shaped to discharge exhaust gas at a different location around the injection cone, and the plurality of flow distribution walls extend into the gap between the mount cylinder and the injection cone so that exhaust gas is distributed around the inlet aperture of the injection cone when exhaust gas flows through the reducing agent mixer.

Clause 32: The reducing agent mixer of any other suitable clause, combination of clauses, or combination of clause limitations, wherein the mixing can includes an outer wall formed to include a can aperture through which the reducing agent delivery device extends, an upstream baffle that defines an upstream side of the internal space and formed to include guide aperture, and a downstream baffle that defines a downstream side of the internal space, the exhaust guide includes an exhaust-distribution duct that extends in the upstream direction from the injection cone and forms an exhaust-receipt opening that opens facing in the upstream direction and that is aligned with the guide aperture so that exhaust moving through the guide aperture enters the exhaust guide for distribution around the inlet aperture of the injection cone when exhaust gas flows through the reducing agent mixer.