Reductant material deposit reduction in exhaust aftertreatment systems

Patent metadata

Field	Value
Publication number	US-9341097-B2
Application number	US-201414151133-A
Country	US
Kind code	B2
Filing date	Jan 9, 2014
Priority date	Mar 15, 2013
Publication date	May 17, 2016
Grant date	May 17, 2016

Abstract

In one non-limiting embodiment, an apparatus for treating exhaust includes a reductant injector, an aftertreatment component including a NO x reduction catalyst, and a pathway for directing exhaust to the aftertreatment component. The pathway includes a constriction zone within which is positioned a mixing member. The constriction zone begins downstream of the reductant injector and upstream from the aftertreatment component. However, other embodiments, forms and applications are also envisioned.

First claim

What is claimed is:

1. An apparatus for treating exhaust, comprising:
a reductant injector;
an aftertreatment component including a NO x reduction catalyst; and
a pathway for directing said exhaust to said aftertreatment component, said pathway including a constriction zone within which is positioned a mixing member, said constriction zone beginning downstream of said reductant injector and upstream of said aftertreatment component,
wherein the pathway includes a first surface upstream of and abutting the mixing member obliquely angled relative to a flow direction of said exhaust through said constriction zone and wherein the first surface defines a boundary of the pathway in a direction towards the mixing member.

2. The apparatus of claim 1 , wherein said pathway further includes a first portion upstream of said constriction zone, a second portion downstream of said constriction zone, and a reduced cross-sectional area in said constriction zone relative to said first and second portions.

3. The apparatus of claim 1 , wherein said constriction zone is defined by an inwardly extending flange extending around said mixing member.

4. The apparatus of claim 3 , wherein said mixing member includes a plurality of spaced apart plates extending between opposite sides of said flange.

5. The apparatus of claim 1 , wherein said constriction zone includes a second surface downstream of the mixing member, obliquely angled relative to a flow direction of said exhaust through said constriction zone, said second surface extending into defining a boundary of the pathway in a direction towards the mixing member.

6. The apparatus of claim 5 , wherein said constriction zone further includes a third surface extending between said first and second surfaces and in said flow direction.

7. The apparatus of claim 5 , wherein said mixing member is positioned between said first and second surfaces.

8. The apparatus of claim 1 , wherein said pathway is structured to direct said exhaust across said mixing member.

9. The apparatus of claim 1 , wherein said mixing member includes a plurality of spaced apart plates.

10. The apparatus of claim 9 , wherein said plates extend in a flow direction of said exhaust through said constriction zone.

11. The apparatus of claim 1 , wherein said reductant injector is obliquely angled relative to a flow direction of said exhaust through said constriction zone.

12. The apparatus of claim 1 , wherein said constriction zone is structured to initiate a velocity increase of said exhaust downstream of said reductant injector.

13. The apparatus of claim 12 , wherein said constriction zone is further structured to initiate said velocity increase of said exhaust upstream of said mixing member.

14. A system, comprising:
an internal combustion engine;
an exhaust flowpath fluidly coupled to said internal combustion engine;
an aftertreatment component disposed in said exhaust flowpath downstream of said internal combustion engine, said component including a NO x reduction catalyst;
a conduit disposed in said exhaust flowpath and including an internal passage, said internal passage including a flow restricting portion, wherein said flow restricting portion includes a reduced cross-sectional area at least partially defined by first and second surfaces obliquely angled relative to a flow direction of said exhaust flowpath through said flow restricting portion, said first surface defining a first boundary of the internal passage in a direction toward the aftertreatment component and said second surface defining a second boundary of the internal passage in a direction away from the aftertreatment component, the first surface being disposed upstream of the second surface and wherein the first surface is formed on an inner surface of the conduit; and
a reductant injector coupled with said conduit upstream of said flow restricting portion, wherein said reductant injector extends at a deviated angle to a flow direction of said exhaust flowpath through said flow restricting portion of said internal passage.

15. The system of claim 14 , further comprising a mixing member positioned in said flow restricting portion.

16. The system of claim 15 , wherein said mixing member includes a plurality of spaced apart plates.

17. The system of claim 16 , wherein said plates extend in a flow direction of said exhaust flowpath through said flow restricting portion.

18. The system of claim 15 , wherein said reductant injector is further structured to direct a reductant dosage into contact with said mixing member.

19. The system of claim 14 , wherein said deviated angle is between 15 degrees and 60 degrees.

20. The system of claim 14 , wherein said flow restricting portion of said internal passage includes a reduced-cross sectional area at least partially defined by an inwardly extending flange.

21. The system of claim 14 , wherein said reductant injector includes an injection end in communication with said internal passage of said conduit at a location offset from a main stream of said exhaust flowpath.

22. The system of claim 12 , further comprising a particulate filter positioned upstream of said aftertreatment component.

23. An article of manufacture, comprising:
a body extending between a proximal end and an opposite distal end;
a flow pathway extending through said body from a proximal opening through said proximal end to a distal opening through said distal end and including a flow restriction zone;
a mounting portion offset from said flow restriction zone in a proximal-distal direction and structured to facilitate mounting of a reductant injector on said body and in communication with said flow pathway; and
a mixing member positioned in said flow restriction zone, wherein said flow restriction zone is structured to initiate a velocity increase of a fluid being passed through said body at a location proximal of a flange associated with said mixing member,
wherein the flow pathway includes a first surface upstream of and abutting the mixing member obliquely angled relative to a flow direction of exhaust through the flow restriction zone, wherein the first surface defines a boundary of the flow restriction zone in a direction towards the mixing member and a second surface downstream of and abutting the mixing member obliquely angled relative to the flow direction of the exhaust through the flow restriction zone wherein the second surface defines a boundary of the flow restriction zone in a direction away from the mixing member.

24. The article of manufacture of claim 23 , wherein said mixing member includes a plurality of spaced apart mixing elements positioned in said flow restriction zone and extending substantially parallel to a portion of said flow pathway extending through said flow restriction zone.

25. The article of manufacture of claim 24 , wherein each of said plurality of mixing elements includes a proximal facing surface and an opposite distal facing surface, said proximal facing surfaces being aligned with one another in a proximal-distal direction.

26. The article of manufacture of claim 23 , wherein said flow restriction zone includes a reduced cross-sectional area at least partially defined by an inwardly extending flange.

27. The article of manufacture of claim 23 , wherein said mounting portion extends upwardly from said flow pathway.

28. A method, comprising:
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Assignees

• Cummins Inc

Inventors

• Bays Mark
• Package Ian A
• Deshmukh Upendra
• Mitchell Douglas
• Drost Jason
• Chiruta Mihai
• Brault Joseph

Classifications

• B01F5/0268

  Operations & Transport · mapped topic

• F01N2240/20

  a flow director or deflector · CPC title

• Y02T10/24

  Cross-Sectional Technologies · mapped topic

• F01N3/2066 Primary

  Selective catalytic reduction [SCR] · CPC title

• F01N3/2892

  Exhaust flow directors or the like, e.g. upstream of catalytic device · CPC title