Exhaust gas/reactant mixing arrangement

Patent metadata

Field	Value
Publication number	US-11585256-B2
Application number	US-202217690232-A
Country	US
Kind code	B2
Filing date	Mar 9, 2022
Priority date	Mar 10, 2021
Publication date	Feb 21, 2023
Grant date	Feb 21, 2023

Abstract

An exhaust gas/reactant mixing arrangement is for an exhaust system of an internal combustion engine for mixing exhaust gas and reactant. The mixing arrangement includes an exhaust gas guide housing extending in the direction of a housing longitudinal axis and a housing wall. The housing wall surrounds and defines an exhaust gas duct accommodating a flow of exhaust gas. A mixing zone is formed between an upstream end wall and a downstream end wall arranged downstream of the upstream end wall. The mixing zone includes a first chamber and a second chamber as well as a reactant dispensing unit carried on the exhaust gas guide housing for dispensing reactant into the first chamber in a reactant main dispensing direction oriented substantially along a reactant dispensing line.

First claim

What is claimed is:

1. An exhaust gas/reactant mixing arrangement for an exhaust system of an internal combustion engine for mixing exhaust gas and reactant, the exhaust gas/reactant mixing arrangement comprising:
an exhaust gas guide housing defining a housing longitudinal axis (G) and extending therealong;
said exhaust gas guide housing including a housing wall surrounding and defining an exhaust gas duct accommodating a flow of exhaust gas therethrough;
an upstream end wall and a downstream end wall arranged downstream of said upstream end wall;
a mixing zone formed between said upstream end wall and said downstream end wall;
said mixing zone including a first chamber and a second chamber;
a reactant dispensing arrangement supported on said exhaust gas guide housing and being configured to disperse reactant (R) into said first chamber in a main dispensing direction (H) oriented along a reactant dispensing line (L);
said exhaust gas duct defining an upstream duct region upstream of said upstream end wall;
said upstream end wall having at least two first inflow openings provided therein to open said upstream duct region to said first chamber, said at least two first inflow openings being provided in said upstream end wall on respective sides of said reactant dispensing line (L), when viewed in a circumferential direction, and being arranged mirror-symmetrically to a plane (E) conjointly defined by said reactant dispensing line (L) and said housing longitudinal axis (G);
said upstream end wall having at least one second inflow opening provided therein to open said upstream duct region to said second chamber;
said exhaust gas duct defining a downstream duct region downstream of said downstream end wall;
said downstream end wall having at least two first outflow openings provided therein to open said first chamber to said downstream duct region, said at least two first outflow openings being arranged on respective sides of said reactant dispensing line (L), when viewed in said circumferential direction, and being arranged mirror-symmetrically to said plane (E);
said downstream end wall having at least one second outflow opening provided therein to open said second chamber to said downstream duct region;
first and second baffles arranged between said first inflow openings and said first outflow openings and extending between said upstream and downstream end walls and adjoining said housing wall and being on respective sides of said reactant dispensing line (L), when viewed in said circumferential direction; and wherein
said first chamber has a first chamber region formed between said first and second baffles and configured to narrow in a reactant main dispensing direction (H), said first chamber further having a second chamber region, said first chamber region being open to said second chamber region, said first and second chamber regions conjointly defining a transition opening whereat said first chamber region is open toward said second chamber region, said second chamber region being configured to start from said transition opening and to lead on both sides of said reactant dispensing line (L) to said first outflow openings.

2. The exhaust gas/reactant mixing arrangement of claim 1 , wherein said first and second chambers are configured so as to permit no fluid connection therebetween.

3. The exhaust gas/reactant mixing arrangement of claim 1 , wherein:
on respective sides of said reactant dispensing line (L), said first inflow openings are arranged closer to said reactant dispensing line (L) than are said first outflow openings, when viewed in said circumferential direction.

4. The exhaust gas/reactant mixing arrangement of claim 1 , wherein at least one of said first and second chamber regions is arranged mirror-symmetrically to said plane (E).

5. The exhaust gas/reactant mixing arrangement of claim 1 , further comprising a partition wall separating said first chamber from said second chamber and extending between said upstream end wall and said downstream end wall.

6. The exhaust gas/reactant mixing arrangement of claim 5 , wherein said partition wall is configured to delimit said first chamber radially on the outside thereof with respect to said second chamber.

7. The exhaust gas/reactant mixing arrangement of claim 6 , wherein said second inflow opening is arranged between said partition wall and said housing wall; and, said partition wall is concavely-shaped toward said first chamber in the region thereof extending along said second inflow opening.

8. The exhaust gas/reactant mixing arrangement of claim 5 , wherein at least one of the following applies:
a) said partition wall extends between said first and second baffles in the circumferential direction along said housing wall; and,
b) said partition wall is arranged mirror-symmetrically to said plane (E).

9. The exhaust gas/reactant mixing arrangement of claim 8 , wherein respective pluralities of said second outflow openings are provided in said downstream end wall in each chamber end region of said second chamber and adjoining one of said baffles and arranged so as to follow one another in said circumferential direction.

10. The exhaust gas/reactant mixing arrangement of claim 9 , wherein said respective pluralities of said second outflow openings are arranged mirror-symmetrically to said plane (E).

11. The exhaust gas/reactant mixing arrangement of claim 1 , wherein at least one of the following applies:
a) said second inflow opening is arranged mirror-symmetrically to said plane (E);
b) said upstream end wall is formed mirror-symmetrically to said plane (E);
c) said downstream end wall is formed mirror-symmetrically to said plane (E); and,
d) said reactant dispensing line (L) extends orthogonally to said housing longitudinal axis (G).

12. An exhaust system for an internal combustion engine, the exhaust system comprising:
an exhaust gas/reactant mixing arrangement including:
an exhaust gas guide housing defining a housing longitudinal axis (G) and extending therealong;
said exhaust gas guide housing including a housing wall surrounding and defining an exhaust gas duct accommodating a flow of exhaust gas therethrough;
an upstream end wall and a downstream end wall arranged downstream of said upstream end wall;
a mixing zone formed between said upstream end wall and said downstream end wall;
said mixing zone including a first chamber and a second chamber;
a reactant dispensing arrangement supported on said exhaust gas guide housing and being configured to disperse reactant (R) into said first chamber in a main dispensing direction (H) oriented along a reactant dispensing line (L);
said exhaust gas duct defining an upstream duct region upstream of said upstream end wall;
said upstream end wall having at least two first inflow openings provided therein to open said upstream duct region to said first chamber, said at least two first inflow openings being provided in said upstream end wall on respective sides of said reactant dispensing line (L), when viewed in a circumferential direction, and being arranged mirror-symmetrically to a plane (E) conjointly defined by said reactant dispensing line (L) and said housing longitudinal axis (G);
said upstream end wall having at least one second inflow opening provided therein to open said upstream duct region to said second chamber;
said exhaust gas duct defining a downstream duct region downstream of said downstream end wall;
said downstream end wall having at least two first outflow openings provided therein to open said first chamber to said downstream duct region, said at least two first outflow openings being arranged on respective sides of

Assignees

• Purem GmbH

Inventors

• Kast Peter

Classifications

• B01D53/9418

  for removing nitrogen oxides by selective catalytic reduction [SCR] using a reducing agent in a lean exhaust gas · CPC title

• F01N3/2892 Primary

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

• Y02A50/20

  Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters · CPC title

• F01N2610/02

  the substance being ammonia or urea · CPC title

• F01N13/0097

  the purifying devices are arranged in a single housing · CPC title