Outlet flow mixers for selective catalytic reduction systems of work vehicles

Patent metadata

Field	Value
Publication number	US-11280239-B2
Application number	US-202016803236-A
Country	US
Kind code	B2
Filing date	Feb 27, 2020
Priority date	Feb 27, 2020
Publication date	Mar 22, 2022
Grant date	Mar 22, 2022

Abstract

A selective catalytic reduction (SCR) system includes a SCR canister including a SCR inlet configured for receiving engine exhaust from a work vehicle and a SCR outlet configured for expelling a treated exhaust flow. The system includes first and second SCR chambers housed within the SCR canister and configured to react mixtures of exhaust reductant and associated first and second portions of the engine exhaust with a catalyst to generate first and second treated exhaust flow portions, respectively. The system includes an outlet chamber positioned between the SCR outlet and the first and second SCR chambers. Moreover, the outlet chamber is configured to combine the first and second treated exhaust flow portions to form the treated exhaust flow. Further, the system includes a chamber mixer positioned upstream of the SCR outlet and configured to promote mixing of the first and second treated exhaust flow portions within the outlet chamber.

First claim

What is claimed:

1. A selective catalytic reduction (SCR) system, the SCR system comprising:
a SCR canister including a SCR inlet configured for receiving engine exhaust from a work vehicle and a SCR outlet configured for expelling a treated exhaust flow;
a first SCR chamber housed within the SCR canister and configured to react a mixture of exhaust reductant and a first portion of the engine exhaust with a catalyst to generate a first treated exhaust flow portion;
a second SCR chamber housed within the SCR canister and configured to react a mixture of exhaust reductant and a second portion of the engine exhaust with a catalyst to generate a second treated exhaust flow portion;
an outlet chamber positioned between the SCR outlet and the first and second SCR chambers, the outlet chamber configured to combine the first treated exhaust flow portion and the second treated exhaust flow portion to form the treated exhaust flow; and
a chamber mixer comprising a plurality of louvered members and positioned upstream of the SCR outlet, the chamber mixer configured to promote mixing of the first and second treated exhaust flow portions within the outlet chamber,
wherein the chamber mixer further comprises a cross-beam oriented perpendicular to the plurality of louvered members such that the chamber mixer defines a first region and a second region of the chamber mixer separated by the cross-beam, wherein each louvered member of plurality of louvered members in the first region is oriented to deflect at least one of the first treated exhaust flow portion or the second treated exhaust flow portion toward a first side of the SCR canister, and wherein each louvered member of the plurality of louvered members in the second region is oriented to deflect at least one of the first treated exhaust flow portion or the second treated exhaust flow portion toward an opposite second side of the SCR canister.

2. The system of claim 1 , further comprising:
a flow conduit in fluid communication with the SCR outlet and configured for receiving the treated exhaust flow expelled from the SCR outlet; and
an exhaust sensor positioned within the flow conduit downstream of the SCR outlet, the exhaust sensor being configured to detect an amount of an emission gas present in the treated exhaust flow.

3. The system of claim 2 , wherein the chamber mixer further includes a flow diverger positioned directly upstream of the exhaust sensor and configured such that at least one of the first treated exhaust flow portion or the second treated exhaust flow portion must flow around the flow diverger before encountering the exhaust sensor.

4. The system of claim 2 , wherein the exhaust sensor is a nitrous oxide (NOx) sensor.

5. The system of claim 1 , wherein the chamber mixer is positioned within an outlet of at least one of the first SCR chamber or second SCR chamber, the plurality of louvered members extending across the outlet of at least one of the first SCR chamber or second SCR chamber.

6. The system of claim 5 , wherein the plurality of louvered members of the chamber mixer is configured to introduce turbulence into at least one of the first treated exhaust flow portion or the second treated exhaust flow portion.

7. The system of claim 1 , wherein the chamber mixer is positioned within the outlet chamber downstream of the first and second SCR chambers, the plurality of louvered members extending across the SCR canister.

8. The system of claim 1 , wherein each louvered member of the plurality of louvered members is oriented to deflect at least one of the first treated exhaust flow portion or the second treated exhaust flow portion to one side of the SCR canister.

9. The system of claim 1 , wherein the chamber mixer defines a center, the plurality of louvered members extending radially outwardly from the center, and wherein the plurality of louvered members are oriented to impart a swirl in at least one of the first treated exhaust flow portion or the second treated exhaust flow portion.

10. An exhaust treatment system for a work vehicle, the system comprising:
an exhaust conduit configured for transmitting engine exhaust from an engine;
a DOC system in flow communication with the exhaust conduit, the DOC system configured to introduce an exhaust reductant into the engine exhaust to form an exhaust/reductant mixture;
a selective catalytic reduction (SCR) system, the SCR system comprising:
a SCR canister including a SCR inlet configured for receiving the exhaust/reductant mixture expelled from the DOC system and a SCR outlet configured for expelling a treated exhaust flow;
a first SCR chamber housed within the SCR canister and configured to react a first portion of the exhaust/reductant mixture with a catalyst to generate a first treated exhaust flow portion;
a second SCR chamber housed within the SCR canister and configured to react a second portion of the exhaust/reductant mixture with a catalyst to generate a second treated exhaust flow portion;
an outlet chamber positioned between the SCR outlet and the first and second SCR chambers, the outlet chamber configured to combine the first treated exhaust flow portion and the second treated exhaust flow portion to form the treated exhaust flow; and
a chamber mixer comprising a plurality of louvered members and positioned upstream of the SCR outlet, the chamber mixer configured to promote mixing of the first and second treated exhaust flow portions within the outlet chamber,
wherein the chamber mixer further comprises a cross-beam oriented perpendicular to the plurality of louvered members such that chamber mixer defines a first region and a second region of the chamber mixer separated by the cross-beam, wherein each louvered member of plurality of louvered members in the first region is oriented to deflect at least one of the first treated exhaust flow portion or second treated exhaust flow portion toward a first side of the SCR canister, and wherein each louvered member of the plurality of louvered members in the second region is oriented to deflect at least one of the first treated exhaust flow portion or second treated exhaust flow portion toward an opposite second side of the SCR canister.

11. The system of claim 10 , further comprising:
a flow conduit in fluid communication with the SCR outlet and configured for receiving the treated exhaust flow expelled from the SCR outlet; and
an exhaust sensor positioned within the flow conduit downstream of the SCR outlet, the exhaust sensor being configured to detect an amount of an emission gas present in the treated exhaust flow.

12. The system of claim 11 , wherein the chamber mixer further includes a flow diverger positioned directly upstream of the exhaust sensor and configured such that at least one of the first treated exhaust flow portion or the second treated exhaust flow portion must flow around flow diverger before encountering the exhaust sensor.

13. The system of claim 10 , wherein the chamber mixer is positioned within an outlet of at least one of the first SCR chamber or the second SCR chamber, the plurality of louvered members extending across the outlet of at least one of the first SCR chamber or the second SCR chamber.

14. The system of claim 10 , wherein the chamber mixer is positioned within the outlet chamber downstream of the first and second SCR chambers, the plurality of louvered members extending across the SCR canister.

15. The system of claim 10 , wherein each louvered member of plurality of louvered members is oriented to deflect at least one of the first treated exhaust flow portion or the second treated exhaust flow portion to

Assignees

• Cnh Ind America Llc

Inventors

• Ghorpade Kaushal
• Morey Daniel Alan
• Abbassi Hesam
• Tamamidis Panos
• Singh Samrendra K

Classifications

• F01N3/2892

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

• F01N11/007

  the diagnostic devices measuring oxygen or air concentration downstream of the exhaust apparatus · CPC title

• B01F23/2132

  using nozzles · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title

• F01N3/2066 Primary

  Selective catalytic reduction [SCR] · CPC title