Mixing subassembly for an exhaust gas system of an internal combustion engine

Patent metadata

Field	Value
Publication number	US-11898484-B2
Application number	US-202318164237-A
Country	US
Kind code	B2
Filing date	Feb 3, 2023
Priority date	Feb 4, 2022
Publication date	Feb 13, 2024
Grant date	Feb 13, 2024

Abstract

A mixing subassembly for an exhaust gas system of an internal combustion engine for mixing exhaust gas, which is discharged by an internal combustion engine, with reactant includes a mixing path which extends in the direction of a mixing path longitudinal axis and which has an upstream mixing path inflow region for receiving exhaust gas and/or reactant in the mixing path. The mixing path includes a core flow channel, through which a first exhaust gas partial flow flows, and a bypass flow channel, through which a second exhaust gas partial flow flows. At least one flow blocking element reduces a flow cross section of the bypass flow channel and is arranged in the bypass flow channel.

First claim

The invention claimed is:

1. A mixing subassembly for an exhaust gas system of an internal combustion engine for mixing exhaust gas discharged by the internal combustion engine with a reactant, the mixing subassembly comprising:
said mixing subassembly defining a mixing path having a longitudinal axis along which said mixing path extends;
said mixing path having an upstream mixing path inflow region for receiving at least one of said exhaust gas and said reactant into said mixing path;
a core flow channel for passing a first exhaust gas partial flow therethrough;
a bypass flow channel for passing a second exhaust gas partial flow therethrough, said bypass flow channel including a covering flow channel annularly surrounding said core flow channel;
said mixing path including an external mixing path housing delimiting said covering flow channel in a radially outward manner and having an inner side facing toward said covering flow channel;
said mixing path including an internal mixing path housing delimiting said core flow channel in a radially outward manner to separate said core flow channel from said covering flow channel and having an outer side facing toward said covering flow channel;
at least two flow blocking elements, each flow blocking element of said at least two flow blocking elements including a flow blocking ring arranged in said covering flow channel to reduce a flow cross section of said covering flow channel;
at least one first flow blocking element of said at least two flow blocking elements being secured to said inner side of said external mixing path housing so as to form a first throughflow region between said least one first flow blocking element and said outer side of said internal mixing path housing, said first throughflow region having a flow cross section reduced with respect to a flow cross section of said covering flow channel upstream of said at least one first flow blocking element and with respect to a flow cross section of said covering flow channel downstream of said at least one first flow blocking element;
at least one second flow blocking element of said at least two flow blocking elements being secured to said outer side of said internal mixing path housing so as to form a second throughflow region between said at least one second blocking element and said inner side of said external mixing path housing, said second throughflow region having a flow cross section reduced with respect to said flow cross section of said covering flow channel upstream of said at least one second flow blocking element and with respect to said flow cross section of said covering flow channel downstream of said at least one second flow blocking element; and,
said first and second flow blocking elements being secured alternately to said external mixing path housing and said internal mixing path housing in a successive manner in the direction of said longitudinal axis of said mixing path.

2. The mixing subassembly of claim 1 , wherein each flow blocking ring of the at least two flow blocking elements completely surrounds said longitudinal axis of said mixing path.

3. The mixing subassembly of claim 1 , wherein each flow blocking element of said at least two flow blocking elements comprises an annular body member having an L-shaped cross section having first and second legs; and, wherein:
said first leg is secured to said inner side of said external mixing path housing and said second leg extends away from said first leg and protrudes radially into said covering flow channel and delimits said throughflow region with said internal mixing path housing; or,
said first leg is secured to said outer side of said internal mixing path housing and said second leg extends away from said first leg and protrudes radially into said covering flow channel and delimits said throughflow region with said external mixing path housing.

4. The mixing subassembly of claim 3 , wherein said annular body member of each flow blocking element is secured with said first leg to one of the following: said external mixing path housing or to said internal mixing path housing by a non-positive-locking connection and/or a materially engaging connection.

5. The mixing subassembly of claim 4 , wherein said materially engaging connection is a welded connection.

6. The mixing subassembly of claim 1 , wherein said first and second flow blocking elements mutually overlap radially.

7. The mixing subassembly of claim 1 , wherein said at least two flow blocking elements are arranged in a region of said upstream mixing path inflow region.

8. The mixing subassembly of claim 1 , further comprising a reactant discharge arrangement for discharging said reactant into said mixing path.

9. The mixing subassembly of claim 8 , wherein said reactant discharge arrangement comprises a mixer.

10. The mixing subassembly of claim 9 , wherein said mixer is configured to expand radially in a direction of a reactant main discharge.

11. The mixing subassembly of claim 8 , wherein said reactant discharge arrangement is configured to discharge said reactant only into said first exhaust gas partial flow.

12. An exhaust gas system comprising:
a mixing subassembly for mixing exhaust gas discharged by an internal combustion engine with a reactant;
the mixing subassembly comprising:
said mixing subassembly defining a mixing path having a longitudinal axis along which said mixing path extends;
said mixing path having an upstream mixing path inflow region for receiving at least one of said exhaust gas and said reactant into said mixing path;
a core flow channel for passing a first exhaust gas partial flow therethrough;
a bypass flow channel for passing a second exhaust gas partial flow therethrough, said bypass flow channel including a covering flow channel annularly surrounding said core flow channel;
said mixing path including an external mixing path housing delimiting said covering flow channel in a radially outward manner and having an inner side facing toward said covering flow channel;
said mixing path including an internal mixing path housing delimiting said core flow channel in a radially outward manner to separate said core flow channel from said covering flow channel and having an outer side facing toward said covering flow channel;
at least two flow blocking elements, each flow blocking element of said at least two flow blocking elements including a flow blocking ring arranged in said covering flow channel to reduce flow cross section of said covering flow channel;
at least one first flow blocking element of said at least two flow blocking elements being secured to said inner side of said external mixing path housing so as to form a first throughflow region between said least one first flow blocking element and said outer side of said internal mixing path housing, said first throughflow region having a flow cross section reduced with respect to a flow cross section of said covering flow channel upstream of said at least one first flow blocking element and with respect to a flow cross section of said covering flow channel downstream of said at least one first flow blocking element;
at least one second flow blocking element of said at least two flow blocking elements being secured to said outer side of said internal mixing path housing so as to form a second throughflow region between said at least one second blocking element and said inner side of said external mixing path housing, said second throughflow region having a flow cross section reduced with respect to said flow cross section of said covering flow channel upstream of said at least one second flow blocking element and with respect to said flow cross section

Assignees

• Purem GmbH

Inventors

• Weinmann Philipp
• Eder Vincent
• Rothfuss Mathias
• Wolf Tobias
• Dentler Michael
• Kauderer Alexander

Classifications

• F01N3/2892 Primary

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

• F01N3/2066

  Selective catalytic reduction [SCR] · CPC title

• F01N2450/22

  by welding or brazing · CPC title

• F01N2610/1453

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

• B01F23/2132 Primary

  using nozzles · CPC title