Dosing and mixing arrangement for use in exhaust aftertreatment

Patent metadata

Field	Value
Publication number	US-11608764-B2
Application number	US-202117222274-A
Country	US
Kind code	B2
Filing date	Apr 5, 2021
Priority date	Jun 22, 2010
Publication date	Mar 21, 2023
Grant date	Mar 21, 2023

Abstract

A dosing and mixing arrangement includes a mixing tube having a constant diameter along its length. At least a first portion of the mixing tube includes a plurality of apertures. The arrangement also includes a swirl structure for causing exhaust flow to swirl outside of the first portion of the mixing tube in one direction along a flow path that extends at least 270 degrees around a central axis of the mixing tube. The arrangement is configured such that the exhaust enters an interior of the mixing tube through the apertures as the exhaust swirls along the flow path. The exhaust entering the interior of the mixing tube through the apertures has a tangential component that causes the exhaust to swirl around the central axis within the interior of the mixing tube. The arrangement also includes a doser for dispensing a reactant into the interior of the mixing tube.

First claim

What is claimed is:

1. An exhaust aftertreatment device, comprising:
an inlet and an outlet;
a main housing body between the inlet and the outlet;
a mixing tube having a first portion within the main housing body and a second portion, the first portion of the mixing tube defining a plurality of apertures, the second portion of the mixing tube forming the outlet, the mixing tube being provided with fins extending inwardly from an inner wall of the mixing tube;
a swirl structure for swirling exhaust around an exterior of the first portion of the mixing tube, the swirl structure including a deflector baffle spaced from the mixing tube;
a doser mount configured to receive a doser adapted to dispense reactant into the mixing tube; and
an exhaust aftertreatment substrate positioned within the main housing body at a location between the inlet and the first portion of the mixing tube, the exhaust aftertreatment substrate defining a center axis that intersects the mixing tube within the main housing body, the deflector baffle being disposed between the exhaust aftertreatment substrate and the mixing tube.

2. The exhaust aftertreatment device of claim 1 , wherein the reactant includes aqueous urea.

3. The exhaust aftertreatment device of claim 1 , wherein the swirl structure includes a swirl housing at least partially surrounding the first portion of the mixing tube.

4. The exhaust aftertreatment device of claim 1 , wherein the swirl structure has a cross-section that gradually decreases along a flow path.

5. The exhaust aftertreatment device of claim 1 , wherein exhaust enters the device through the inlet and passes through the exhaust aftertreatment substrate, where the exhaust is initially treated, and then out through the outlet.

6. The exhaust aftertreatment device of claim 1 , wherein the second portion of the mixing tube projects outwardly from the main housing body.

7. The exhaust aftertreatment device of claim 1 , wherein the exhaust aftertreatment substrate is a diesel particulate filter or a catalytic converter.

8. The exhaust aftertreatment device of claim 1 , wherein the second portion of the mixing tube does not have any apertures.

9. The exhaust aftertreatment device of claim 8 , wherein the mixing tube has a first end positioned adjacent the first portion of the mixing tube and a second end positioned adjacent the second portion of the mixing tube, and wherein the second end forms an outlet of the mixing tube.

10. The exhaust aftertreatment device of claim 9 , wherein the first end of the mixing tube is closed to exhaust flow, and wherein the doser mount is disposed mounted at the first end of the mixing tube.

11. The exhaust aftertreatment device of claim 1 , wherein an inlet pipe forming the inlet is attached to a side of the main housing body and extends out from the side of the main housing body in an angled tangential direction in relation to the mixing tube, wherein exhaust enters the main housing body through the inlet pipe; wherein the swirl structure is configured to cause exhaust flow to swirl outside of the first portion of the mixing tube in one rotational direction along a flow path around a central axis of the mixing tube; wherein the exhaust enters an interior of the mixing tube through the apertures as the exhaust swirls along the flow path; and wherein the exhaust entering the interior of the mixing tube through the apertures has a tangential component that causes the exhaust to swirl around the central axis of the mixing tube within the interior of the same.

12. The exhaust aftertreatment device of claim 11 , wherein the mixing tube has a generally constant diameter along its length.

13. The exhaust aftertreatment device of claim 11 , wherein the flow path extends at least 270 degrees around the central axis of the mixing tube.

14. An exhaust aftertreatment device, comprising:
an inlet and an outlet;
a main housing body between the inlet and the outlet;
a mixing tube having a first portion within the main housing body and a second portion, the first portion of the mixing tube defining a plurality of apertures, the second portion of the mixing tube forming the outlet, the mixing tube being provided with fins extending inwardly from an inner wall of the mixing tube;
a swirl structure configured to swirl exhaust around the first portion of the mixing tube, the swirl structure extending from a first end to an opposite second end, the swirl structure having a cross-section that gradually decreases between the first and second ends;
a doser mount configured to receive a doser adapted to dispense reactant into the mixing tube; and
an exhaust aftertreatment substrate positioned within the main housing body at a location between the inlet and the first portion of the mixing tube, the substrate defining a center axis that intersects the mixing tube within the main housing body.

15. The exhaust aftertreatment device of claim 14 , wherein an inlet pipe forming the inlet is attached to a side of the main housing body and extends out from the side of the main housing body in an angled tangential direction in relation to the mixing tube; and wherein exhaust enters the main housing body through the inlet pipe.

16. The exhaust aftertreatment device of claim 14 , wherein the mixing tube has a first end positioned adjacent the first portion of the mixing tube and a second end positioned adjacent the second portion of the mixing tube, wherein the first end of the mixing tube is closed to exhaust flow, wherein the doser mount is disposed at the first end of the mixing tube, and wherein the second end forms an outlet of the mixing tube.

17. The exhaust aftertreatment device of claim 14 , wherein the swirl structure includes a swirl housing at least partially surrounding the first portion of the mixing tube.

18. The exhaust aftertreatment device of claim 14 , wherein the second portion of the mixing tube does not have any apertures.

19. The exhaust aftertreatment device of claim 14 , wherein the swirl structure is configured to cause exhaust flow to swirl outside of the first portion of the mixing tube in one rotational direction along a flow path.

20. The exhaust aftertreatment device of claim 19 , wherein the flow path extends at least 270 degrees around a central axis of the mixing tube at an exterior of the mixing tube.

21. An exhaust aftertreatment device, comprising:
an inlet and an outlet;
a main housing body between the inlet and the outlet, wherein an inlet pipe forming the inlet is attached to a side of the main housing body and extends out from the side of the main housing body in an angled tangential direction in relation to the mixing tube, wherein exhaust enters the main housing body through the inlet pipe;
a mixing tube having a first portion within the main housing body and a second portion, the first portion of the mixing tube defining a plurality of apertures, wherein the exhaust entering the interior of the mixing tube through the apertures has a tangential component that causes the exhaust to swirl around a central axis of the mixing tube within the interior of the same, the second portion of the mixing tube forming the outlet, the mixing tube being provided with fins extending inwardly from an inner wall of the mixing tube;
a swirl structure for swirling exhaust around an exterior of the first portion of the mixing tube, wherein the swirl structure is configured to cause exhaust flow to swirl outside of the first portion of the mixing tube in one rotational direction alo

Assignees

• Donaldson Co Inc

Inventors

• De Rudder Korneel
• Chauvin Corine

Classifications

• B01F2025/931

  Flow guiding elements surrounding feed openings, e.g. jet nozzles · CPC title

• F01N3/36

  Arrangements for supply of additional fuel · CPC title

• F01N2610/1453

  Sprayers or atomisers; Arrangement thereof in the exhaust apparatus · CPC title

• F01N3/2066 Primary

  Selective catalytic reduction [SCR] · CPC title

• F01N2470/02

  Tubes being perforated · CPC title