Diesel exhaust fluid deposit mitigation

Patent metadata

Field	Value
Publication number	US-10024213-B2
Application number	US-201615361846-A
Country	US
Kind code	B2
Filing date	Nov 28, 2016
Priority date	Oct 14, 2013
Publication date	Jul 17, 2018
Grant date	Jul 17, 2018

Abstract

One form of the present application is an apparatus including an internal combustion engine structured to produce an exhaust flow, an exhaust system structured to receive the exhaust flow, and a reductant injector structured to inject reductant into a primary passage of the exhaust system upstream of a catalyst. The apparatus further includes an injector passage structured to receive a portion of exhaust upstream of the injector and further structured to flow the exhaust into the primary passage around the injector in a manner such that deposit formation is reduced.

First claim

What is claimed is:

1. A system for use with an internal combustion engine that is operable to produce an exhaust gas flow, the system comprising:
a reductant injector configured to release a reductant into the exhaust gas flow;
a catalyst located downstream of the reductant injector; and
an exhaust gas passageway configured to receive the exhaust gas flow and having a bend, wherein the reductant injector is disposed at the bend, and wherein at least a portion of the bend is downstream from the reductant injector;
wherein the exhaust gas passageway includes a primary flow path, an injector flow path separated from the primary flow path by a first wall, and a bypass flow path separated from the primary flow path by a second wall, at least a portion of each of which is located at the bend,
wherein the injector flow path is located on a first side of the primary flow path, which is a side on which the reductant injector is located, and
wherein the bypass flow path is located on a second side of the primary flow path, opposite the first side.

2. The system of claim 1 , further comprising an orifice disposed within the bend, wherein the orifice comprises a first flow diverter located in an interior of the exhaust gas passageway and upstream of the reductant injector, wherein the first flow diverter, in use, routes a first portion of the exhaust gas flow across a tip of the reductant injector.

3. The system of claim 2 , wherein the orifice further comprises a second flow defining the bypass flow path, the second flow diverter including an opening located upstream of the reductant injector, the opening in fluid receiving communication with a second portion of the exhaust gas flow and in fluid providing communication with the bypass pass flow path.

4. The system of claim 3 , further comprising at least one mixing device, each of the at least one mixing device disposed downstream of the reductant injector, wherein each of the at least one mixing device comprises at least one aperture in fluid receiving communication with the bypass flow path and in fluid providing communication with the exhaust gas passageway.

5. The system of claim 1 , wherein the reductant injector is disposed perpendicularly relative to the exhaust gas flow and, in use, releases the reductant towards a centerline of the exhaust gas flow.

6. The system of claim 1 , wherein the internal combustion engine is a diesel engine, wherein at least a portion of the reductant is urea, and wherein the catalyst comprises at least a portion of a selective catalytic reduction bed.

7. The system of claim 1 , wherein the reductant injector is an airless injector.

8. The system of claim 1 , further comprising a mixer disposed along a cross-sectional area of the exhaust gas passageway.

9. The system of claim 8 , wherein the mixer occupies less than a full cross-sectional area of the exhaust gas passageway.

10. The system of claim 8 , wherein the mixer occupies a full cross-sectional area of the exhaust gas passageway.

11. The system of claim 4 , wherein the bypass flow path extends annularly around at least a portion of a circumference of the exhaust gas passageway.

12. An apparatus for use with an internal combustion engine that is operable to produce an exhaust gas flow, the apparatus comprising:
an exhaust system configured to receive the exhaust flow;
a reductant injector configured to inject reductant at a location upstream of a catalyst;
a primary flow path;
an injector flow path separated from the primary flow path by a first wall, the injector flow path being in fluid receiving communication with a first upstream location of the primary flow path relative to the reductant injector and in fluid providing communication with a portion of the primary flow path that comprises the reductant injector, in use, the injector flow path receiving a first portion of the exhaust flow upstream of the reductant injector and routing the first portion of the exhaust flow across a reductant injector tip, wherein the first portion of the exhaust flow passes through the injector flow path in parallel with the exhaust flow in the primary flow path; and
a bypass flow path separated from the primary flow path by a second wall, the bypass flow path being in fluid receiving communication with a second upstream location of the primary flow path relative to the reductant injector and in fluid providing communication with a downstream location of the primary flow path relative to the reductant injector, wherein, in use, a second portion of the exhaust flow passes through the bypass flow path in parallel with the exhaust flow in the primary flow path,
wherein the injector flow path is located on a first side of the primary flow path, which is a side on which the reductant injector is located, and
wherein the bypass flow path is located on a second side of the primary flow path, opposite the first side.

13. The apparatus of claim 12 , wherein the reductant injector is located near a bend in the exhaust system; wherein optionally
the bend is a 90 degree bend and wherein the reductant injector is located on an outer radius of the bend.

14. The apparatus of claim 12 , wherein the bypass flow path further comprises a mixer located near a bypass flow path exit.

Assignees

• Cummins Emission Solutions Inc
• Cummins Emission Solutions Inc

Inventors

• Mitchell Douglas A
• Chiruta Mihai
• Henry Lindsey R
• Alonzo Jim

Classifications

• F01N3/2892

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

• F01N3/2066 Primary

  Selective catalytic reduction [SCR] · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title

• F01N2610/1453

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

• F01N3/28

  Construction of catalytic reactors · CPC title