Dosing and mixing arrangement for use in exhaust aftertreatment

Patent metadata

Field	Value
Publication number	US-11465108-B2
Application number	US-202117216159-A
Country	US
Kind code	B2
Filing date	Mar 29, 2021
Priority date	Sep 13, 2013
Publication date	Oct 11, 2022
Grant date	Oct 11, 2022

Abstract

Dosing and mixing exhaust gas includes directing exhaust gas towards a periphery of a mixing tube that is configured to direct the exhaust gas to flow around and through the mixing tube to effectively mix and dose exhaust gas within a relatively small area. Some mixing tubes include a slotted region and a non-slotted region. Some mixing tubes include a louvered region and a non-louvered region. Some mixing tubes are offset within a mixing region of a housing.

First claim

What is claimed is:

1. An exhaust treatment system comprising:
a housing defining an interior bounded by an interior surface of the housing, the housing also defining a doser mounting location;
an inlet leading into the interior of the housing;
an outlet leading out of the interior of the housing, the outlet opposing the doser mounting location;
a conduit coupled to the housing, the conduit having an annular exterior surface formed about a conduit axis and extending between opposite first and second ends, the first end of the conduit being coupled to the housing at the doser mounting location, the conduit being oriented relative to the housing so that the conduit axis extends through the outlet, the conduit having a louvered section and a non-louvered section disposed within the interior of the housing, the louvered section including a plurality of louvers disposed along a first continuous circumferential distance of the annular exterior surface, each of the louvers being disposed at a respective slot, the non-louvered section extending along a second continuous circumferential distance of the annular exterior surface that combined with the first continuous circumferential distance forms a full circumference of the annular exterior surface, the second continuous circumferential distance being larger than a circumferential distance of any of the slots and any space between the slots, the annular exterior surface being spaced from the interior surface of the housing about the full circumference to define a continuous open volume extending around the conduit, wherein the conduit is solid around a full circumference of the conduit at the outlet, and wherein the slotted region extends 200° to 350° around the conduit.

2. The exhaust treatment system of claim 1 , wherein the conduit extends through the outlet so that the second end of the conduit is disposed external of the housing.

3. The exhaust treatment system of claim 1 , wherein the slotted region extends 210° to 330° around the conduit.

4. The exhaust treatment system of claim 1 , wherein a majority of the conduit is disposed within the interior of the housing.

5. The exhaust treatment system of claim 1 , wherein the inlet faces in a different direction from the outlet.

6. The exhaust treatment system of claim 5 , wherein the inlet faces generally transverse to the outlet.

7. The exhaust treatment system of claim 1 , wherein the slots have a common width.

8. The exhaust treatment system of claim 1 , wherein the first continuous circumferential distance is larger than the second continuous circumferential distance.

9. The exhaust treatment system of claim 1 , further comprising a filter substrate disposed upstream of the conduit.

10. The exhaust treatment system of claim 9 , wherein the filter substrate is disposed in a separate housing.

11. The exhaust treatment system of claim 9 , wherein the filter substrate is disposed in the housing to form a unit.

12. The exhaust treatment system of claim 1 , wherein the conduit has a length extending between the first and second ends, and wherein the louvered section is disposed along a majority of the length of the conduit.

13. The exhaust treatment system of claim 1 , wherein a reference axis extending through the inlet intersects the conduit.

14. An exhaust treatment system comprising:
a housing defining an interior, the housing defining an inlet leading into the interior along an inlet axis; and
a conduit having a first portion disposed within the interior of the housing and a second portion external of the housing, the first portion being larger than the second portion, the conduit having an annular surface surrounding a conduit axis that extends between opposite first and second axial ends of the conduit, the first portion of the conduit defining an exhaust flow entrance region through the annular surface of the conduit, the second portion of the conduit defining an exhaust flow exit through the second axial end of the conduit, the exhaust flow exit being non-parallel with the inlet of the housing, the exhaust flow entrance region including a plurality of slots, the exhaust flow entrance region having a length extending along the conduit axis, wherein a ratio of the length of the exhaust flow entrance region and a diameter of the conduit is 1 to 3, and the first portion of the conduit also including a non-slotted region at a common axial location along the conduit axis as the exhaust flow entrance region, the non-slotted region being circumferentially spaced from the exhaust flow entrance region, the non-slotted region having a larger circumferential distance than any individual one of the slots at the exhaust flow entrance region and any space between the slots, and the slotted region extends 200° to 350° around the conduit.

15. The exhaust treatment system of claim 14 , wherein the slotted region extends 210° to 330° around the conduit.

16. The exhaust treatment system of claim 14 , wherein the housing defines a doser mounting location aligned with the first axial end of the conduit.

17. The exhaust treatment system of claim 14 , wherein the exhaust flow entrance region includes louvers disposed at the slots.

18. The exhaust treatment system of claim 17 , wherein each slot has a corresponding louver.

19. The exhaust treatment system of claim 14 , wherein the exhaust flow entrance region includes circumferential gaps between the slots, wherein the first portion of the conduit defines a non-slotted region disposed circumferentially between two of the slots, and the gaps having a common circumferential distance that is less than a third of the circumferential distance of the non-slotted region.

Assignees

• Donaldson Co Inc

Inventors

• Whitten Matthew S
• Hoppenstedt Bruce Bernard

Classifications

• F01N13/009

  having two or more separate purifying devices arranged in series · CPC title

• B01F25/10

  Mixing by creating a vortex flow, e.g. by tangential introduction of flow components · CPC title

• F01N3/035

  with catalytic reactors · CPC title

• B01F23/2132 Primary

  using nozzles · CPC title

• B01F2025/931

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