DE102017101749A1 - Mixer element for mixing a fluid in an exhaust gas of an internal combustion engine and exhaust line for an internal combustion engine - Google Patents

Abstract

The invention relates to a mixer element (1) for mixing a fluid (51) into an exhaust gas (50) of an internal combustion engine, wherein the mixer element (1) can be arranged in an exhaust line (70) of the internal combustion engine, comprising a first guide section (20) for generating a turbulence of the exhaust gas (50) and a mixing section (30) for mixing the injected fluid (51) with the fluidized exhaust gas (50) to an exhaust gas-fluid mixture (52), wherein with respect to a flow direction (60) of the exhaust gas (50 ) the first guide section (20) is arranged in front of the mixing section (30). Furthermore, the invention relates to an exhaust line (70) for an internal combustion engine, comprising an injection element (75), a tubular element (71) and a mixer element (1), wherein the mixer element (1) in the tubular element (71) is arranged.

Description

The present invention relates to a mixing element for mixing a fluid in an exhaust gas of an internal combustion engine. Furthermore, the invention relates to an exhaust system for an internal combustion engine.

In modern internal combustion engines, especially in diesel engines, it is known to provide cleaning devices for the exhaust gas in an exhaust line of the internal combustion engine. Through these cleaning devices, which may include, for example, catalysts and / or particulate filter, the exhaust gas can be cleaned, for example, to meet legal requirements. In order to achieve these legal targets, for example for nitrogen oxide emissions, SCR catalysts are often used in exhaust gas trains of diesel engines. Selective catalytic reduction (SCR) is used in these SCR catalysts to selectively remove these nitrogen oxides from the exhaust gas. To initiate this catalytic process, an ammonia or urea-water mixture is often injected into the exhaust line. In order for the catalytic reactions to be particularly effective, as complete a vaporization of the ammonia or urea as possible and thorough mixing with the exhaust gas are necessary. For mixing elements are used, as for example from the US 2014/033686 A1 are known. It may happen that in exhaust strands due to structural conditions just such a uniform mixing and evaporation of the injected fluid in the exhaust gas is not possible. This can be caused for example by a structurally required small dimensions of the exhaust system. Also often an impact of the fluid on an outer wall of the exhaust line can often not be avoided, so that there is an increased risk for the formation of deposits. A reduction of the mixing and in particular a non-complete evaporation of the ammonia or urea can thereby occur.

It is therefore an object of the present invention to at least partially overcome the disadvantages described above. In particular, it is an object of the present invention to provide a mixer element and an exhaust line, which in a particularly simple and cost effective manner to improve a uniform mixing and evaporation of a fluid introduced into an exhaust gas, in particular a deposition of the fluid on a surface of the mixer element or . of the exhaust system should be avoided.

The above object is achieved by a mixer element for mixing a fluid in an exhaust gas of an internal combustion engine having the features of independent claim 1. Further, the object is achieved by an exhaust system for an internal combustion engine with the features of independent claim 10. Further features and details of the invention result from the subclaims, the description and the drawings. In this case, features and details that are described in connection with the mixer element according to the invention, of course, also in connection with the exhaust line according to the invention and in each case vice versa, so that with respect to the disclosure of the individual aspects of the invention always reciprocal reference is or may be.

According to a first aspect of the invention, the object is achieved by a mixer element for mixing a fluid into an exhaust gas of an internal combustion engine, wherein the mixer element can be arranged in an exhaust line of the internal combustion engine, comprising a first guide section for generating a turbulence of the exhaust gas and a mixing section for mixing the exhaust gas injected fluid with the turbulated exhaust gas to an exhaust gas-fluid mixture, wherein with respect to a flow direction of the exhaust gas, the first guide portion is disposed in front of the mixing section, and further wherein the mixer element has a second guide portion for mixing of the mixture guided past the exhaust gas in the exhaust gas-fluid Mixture, wherein the second guide portion is arranged with respect to the flow direction of the exhaust gas after the mixing section.

An inventive mixer element is provided for use in an exhaust line of an internal combustion engine. For this, the mixer element according to the invention can be arranged in the exhaust system of the internal combustion engine. A turbulence of the exhaust gas is generated by a first guide section of the mixer element. Such turbulence, into which, in particular, the fluid to be admixed is injected, can already provide good mixing of the exhaust gas and the injected fluid at the beginning of the mixing process. The fluid used may preferably be an ammonia and / or urea-water mixture in order to enable the use of an SCR catalyst for the removal of nitrogen oxides from the exhaust gas. The mixing of the fluid and the exhaust gas is further enhanced by the mixing section. In this case, the first guide section and the mixing section are arranged with respect to a flow direction of the exhaust gas in such a way that first the first guide section and then the mixing section are flowed through by the exhaust gas. This can ensure that exhaust gas flows through the mixing section, which has already been swirled through the first guide section. An even better one Mixing of the exhaust gas with the injected fluid can be made possible thereby.

Essential to the invention it is provided that the mixer element has a second guide section, which is designed for mixing further exhaust gas into the exhaust-fluid mixture, which is present after flowing through the mixing section. For this, the further exhaust gas is guided past the mixing section and mixed into the exhaust-fluid mixture through the second guide section. A first advantage, which results from this, is that a further mixing of the exhaust gas and the fluid in the resulting exhaust gas-fluid mixture is further improved by this re-mixing of exhaust gas. Furthermore, hot exhaust gas flows around the mixing section as a result of the passage of the exhaust gas, preferably completely around it, and is thereby heated. A deposit of fluid impinging on a surface of the mixing section can thereby be safely avoided. A particularly good evaporation of the fluid can thus be achieved. In summary, therefore, a particularly good mixing and evaporation of a fluid in an exhaust gas can be achieved by a mixer element according to the invention, wherein, in particular, deposits of the fluid on surfaces of the mixer element and / or the exhaust line can be avoided.

Furthermore, it may be provided in a mixer element according to the invention that the mixer element has a base body, wherein the first guide section, the mixing section and the second guide section are arranged directly adjacent to each other and / or in the base body, in particular the main body, the first guide section, the mixing section and the second guide portion are integrally formed. By such a base body, a particularly compact embodiment of a mixer element according to the invention can be provided. In this case, the base body can be designed such that the first guide section, the mixing section and / or the second guide section are formed as part of the base body. Due to the direct adjacently disposed arrangement of the first guide section, the mixing section and the second guide section, an unnecessary space requirement can be avoided by a mixer element according to the invention. By a one-piece design of a base body, which has as part of the first guide section, the mixing section and the second guide section, this compact design of a mixer element according to the invention can be further increased.

The first guide portion may be cylindrical. In an alternative variant, the first guide section may be conical.

According to a further development of a mixer element according to the invention, it can further be provided that the main body has an injection opening through which the fluid can be injected into the interior of the mixer element, wherein the injection opening is arranged upstream of the first guide section with respect to the flow direction. In this way it can be made possible that the mixing of the fluid into the exhaust gas in the interior of the mixer element is vornehmbar. By injecting the fluid upstream of the first guide section, it can further be ensured that the fluid is injected into already swirled exhaust gas. This may also allow the entire mixer element to be used for mixing the fluid and the exhaust gas. A particularly effective mixing of the exhaust gas and the fluid can thereby be made possible.

Also, a mixer element according to the invention may be designed such that the first guide section and / or the second guide section have guide elements, in particular guide plates, for guiding the exhaust gas into the interior of the mixer element. By such guide sections can be particularly easily ensured that the exhaust gas is conducted into the interior of the mixer element. In particular, such a guide elements can also influence a flow direction of the exhaust gas in the interior of the mixer element. In particular, such guide elements, which may be formed, for example, as baffles, may be formed as notches in a surface of the respective guide section. Furthermore, by providing a plurality of such guide elements, a particularly good control of a flow direction of the exhaust gas in the interior of the mixer element according to the invention can be provided.

A mixer element according to the invention can also be further developed such that the first guide section and / or the second guide section have inlet openings for a radial inlet of the exhaust gas into the interior of the guide sections, the guide elements for guiding the exhaust gas being arranged inside the guide sections at the inlet openings. By such a radial inlet of the exhaust gas into the interior of the guide sections and thereby into the interior of the mixer element, a circular turbulence of the exhaust gas can be generated in the interior of the mixer element. Particularly preferably, such a circular turbulence can cause an additional, substantially circular flow of the exhaust gas about an axis, which substantially corresponds to the general flow direction of the exhaust gas in the exhaust system. By this circular turbulence, which is superimposed by the general flow direction, the mixing and mixing of the fluid in the exhaust gas can be further improved.

According to a particularly preferred further development of a mixer element according to the invention, it can further be provided that the guide elements of the first guide section and the guide elements of the second guide section guide the exhaust gas into the interior of the first guide section and the second guide section in an at least substantially identical inlet direction. In this way it can be ensured that the generated turbulences, in particular the generated circular turbulences, have the same direction of rotation. A mutual reinforcement of these turbulences can be achieved. The overall achievable mixing of the injected fluid and the exhaust gas in the mixer element according to the invention can be further increased.

Also, a mixer element according to the invention can be designed so that the mixing section has blocking elements, in particular blade-like blocking elements, with a blocking surface, wherein the blocking surface has an acute angle with a rectilinear flow direction. The rectilinear flow direction in this case preferably corresponds essentially to the general flow direction of the exhaust gas in the exhaust gas system. The blocking surfaces of the blocking elements prevent linear penetration along this throughflow direction. Droplets of the injected fluid which move substantially along this rectilinear flow direction can thus not pass through the mixing section. In this way it can be reliably avoided that droplets of the injected fluid are still present in the exhaust-fluid mixture after the mixer element. In this case, the blocking surfaces of the individual blocking elements form a continuous surface only in relation to the rectilinear flow direction, so that a flow of the exhaust gas-fluid mixture continues to be possible between the individual blocking elements. For this purpose, the exhaust gas-fluid mixture is deflected when hitting the blocking elements and passed between the individual blocking elements. Only the fluid droplets are stopped by the blocking elements as described above. As a result of the flow around the mixing section with further exhaust gas, the blocking elements are also heated, as a result of which evaporation of the fluid droplets striking the blocking elements is promoted. Deposits of the injected fluid on the blocking elements can be prevented. Preferably, it may be provided that the blocking elements are arranged such that a flow of the exhaust gas-fluid mixture between the individual blocking elements through a circular turbulence, which was generated by guide elements of the first guide section, is reinforced and supported.

According to a particularly preferred further development of a mixer element according to the invention, it can further be provided that the blocking elements overlap at least in regions with respect to the rectilinear flow direction. With respect to the rectilinear flow direction can be ensured by these overlap areas that the blocking surfaces of the individual locking elements seamlessly merge into one another. As a result of this at least partially overlapping of the blocking elements, even greater security against penetration of the mixing section by fluid droplets can thus be provided.

Furthermore, it may be provided in a mixer element according to the invention that the mixer element has at least one mounting portion for mounting in a mounting position in a pipe element of the exhaust line, wherein in the mounting position between an outer wall of the mixing section and an inner wall of the tubular element, a bypass gap is formed. By such a mounting portion can be ensured that the mixer element can be arranged safely and reproducibly in a designated mounting position in the pipe element of the exhaust system. In particular, it can be ensured that a bypass gap is formed between an outer wall of the mixing section and an inner wall of the tubular element. In this way, a flow around the mixing section through exhaust gas can be achieved particularly easily. The mixing section can be heated thereby, whereby on the one hand an even better evaporation of the injected fluid in the mixing section can be made possible and on the other deposits of the fluid or reaction products of the fluid can be rented on elements of the mixing section. In this case, in particular, this bypass gap may in particular be provided completely with respect to the outer wall of the mixing section, so that exhaust gas can flow around the complete mixing section. This can in particular be achieved, for example, in that both the pipe element and the mixer element are at least substantially cylindrical in the region of the mixing section, wherein the outer wall of the mixing section has a smaller radius than the inner wall of the pipe element.

According to a second aspect of the invention, the object is achieved by an exhaust system for an internal combustion engine, comprising an injection element, a tubular element and a mixer element, wherein the mixer element is arranged in the tubular element. An exhaust line according to the invention is characterized in that the mixer element according to the first aspect of the invention is formed. Accordingly brings an inventive Exhaust line, the same advantages as they have been explained in detail with respect to a mixer element according to the invention according to the first aspect of the invention.

In an exhaust gas line according to the invention, it can preferably be provided that a bypass gap, in particular a circumferential annular gap, is formed in the pipe element at least between an outer wall of the mixing section of the mixer element and an inner wall of the pipe element. In this way it can be ensured that the mixing section of the mixer element can be flowed around outside by exhaust gas. A heating of the mixing section of the mixer element by the flowing exhaust gas can be ensured particularly simple. An evaporation of the injected fluid in the mixing section can thereby be improved and deposits of the fluid on surfaces of the mixing section can be reliably avoided.

Furthermore, an exhaust line according to the invention can be designed in a further development such that a flow element is arranged in the pipe element and / or on the mixer element, the flow element covering a section of a free flow cross section of the pipe element and the bypass gap for generating a directed flow around the mixer element with exhaust gas. In this case, the flow element may be formed as part of the tubular element and / or as part of the mixer element. Covering according to the invention may preferably mean that a flow of the exhaust gas is blocked in or through these covered areas by the flow element. Thus, for example, one half of the free flow cross section of the tubular element and / or the entire bypass gap can be covered by the flow element particularly preferably. The exhaust gas can thereby flow around the mixer element in one direction only. In this way, a swirl can be generated in the exhaust gas in a particularly simple manner, which can be further enhanced by the various configurations of the elements of the mixer element, for example the first guide section and / or the mixing section and / or the second guide section. An even better mixing of the exhaust gas and the injected fluid to an exhaust gas-fluid mixture can be achieved.

Preferably, an exhaust system according to the invention can be further developed such that a contact section is arranged on the mixer element with respect to the flow direction of the exhaust gas after the second guide section, wherein the bypass gap ends by a positive contact of the contact section on the inner wall of the tubular element. In this way it can be ensured that exhaust gas, which is conducted past the mixing section, is conducted completely through the second guide section into the interior of the mixer element. A flow of exhaust gas through the entire mixer element, whereby this exhaust gas would not be used thereby for the formation of the exhaust gas-fluid mixture, can thereby be safely avoided. All the exhaust gas is used for mixing with the fluid in the mixer element in the exhaust gas line according to the invention. A particularly good mixing of the exhaust gas with the injected fluid can be made possible.

Also, an exhaust line according to the invention may be designed so that the tubular element is formed substantially U-shaped with two legs and a base, wherein in particular the mixer element is arranged at a transition between a leg and the base. By means of such a U-shaped tubular element, a particularly space-saving arrangement of a mixer element according to the invention in an exhaust gas line according to the invention can be provided. In particular, by arranging the mixer element at a transition between a limb and a base of the U-shaped tube element by the thereby enabled radial flow of the mixer element by exhaust gas generating a circular turbulence by the first and / or second guide portion can be supported. This generation of circular turbulences can preferably be assisted by the flow element described above. An even better turbulence of the exhaust gas in the interior of the mixer element and thereby an even better mixing of the exhaust gas with the injected fluid can be provided thereby.

It can also be provided in an exhaust line according to the invention that the exhaust line comprises a catalyst and an SCR particulate filter, wherein the tubular element is arranged with the mixing element arranged therein between the catalyst and the SCR particulate filter. By such a catalyst, which may be formed, for example, in diesel internal combustion engines as a diesel oxidation catalyst (DOC) with or without nitrogen oxide and such a particulate filter, a particularly good emission control can be provided in the exhaust system according to the invention. In this case, the particulate filter is particularly preferably designed as an SCR particulate filter, as a result of which, in particular, nitrogen oxides can be selectively removed from the exhaust gas in the particulate filter. The ammonia or urea necessary for this selective removal of the nitrogen oxides can be mixed into the exhaust gas by the mixer element. By arranging the mixer element in the tubular element between the catalytic converter and the SCR particle filter, this mixing in of the necessary fluid can be provided in a particularly simple manner. Particularly preferred in one U-shaped configuration of the tubular element, the catalyst and the SCR particulate filter can be arranged one above the other. A further reduction of the necessary installation space for an exhaust gas line according to the invention can be provided thereby.

Further advantages, features and details of the invention will become apparent from the following description in which, with reference to the drawings, embodiments of the invention are described in detail. The features mentioned in the claims and in the description may each be essential to the invention individually or in any desired combination. Elements with the same function and mode of action are provided with the same reference numerals.

They show schematically:

1 a mixer element according to the invention,

2 an inventive mixer element in an exploded view,

3 a mixing section of a mixer element according to the invention,

4 a part of an exhaust line according to the invention,

5 a part of an exhaust line according to the invention in a first sectional view, and.

6 a part of an exhaust line according to the invention in a second sectional view.

In the 1 . 2 such as 3 is an embodiment of a mixer element according to the invention 1 shown in different views. In the following, therefore, these three figures are described together, with the similarities and the differences of the individual figures will be discussed separately. The illustrated mixer element according to the invention 1 has in particular a main body 10 on. The main body 10 in particular includes a first guide section 20 , a mixing section 30 and a second guide section 40 which are arranged in this adjacent. At one end of the body 10 is also an injection port 11 arranged in which a fluid 51 , For example, ammonia and / or urea, into the interior of the mixer element 1 can be injected. For an arrangement of the mixer element 1 in a tubular element 71 an exhaust line 70 (not shown) shows the body 10 also mounting sections 12 on. In a mixer element according to the invention 1 can this fluid 51 in exhaust 50 be mixed. For the exhaust gas flows through 50 the mixer element 1 along a general flow direction 60 , Through inlet openings 21 in the first section 20 is the exhaust gas 50 inside the mixer element 1 directed. By guide elements 22 , for example, as notches of a surface of the first guide section 20 inside the mixer element 1 can be formed, while the exhaust gas 50 so radially into the interior of the mixer element 1 directed that there arise circular turbulence. Into these circular eddies of exhaust gas 50 becomes the fluid 51 injected. This results already here a good mixing of the fluid 51 and the exhaust gas 50 , This mixing can flow through the mixing section 30 that in the general flow direction 60 after the first lead 20 is arranged to be reinforced again. For that are in the mixing section 30 Shovel-like blocking elements 31 provided with a flow direction 61 the exhaust gas 50 or of the fluid 51 take an acute angle, see in particular 3 , This can be achieved on the one hand, that the mixing of the exhaust gas 50 and the fluid 51 is increased again. Furthermore, through these restricted areas 32 a penetration of the mixing section 30 through droplets of the fluid 51 safely avoided. In particular, the locking elements can do this 31 or the restricted areas 32 the blocking elements 31 overlap. As a result, droplets of the fluid meet 51 on these restricted areas 32 the blocking elements 31 , making sure they pass through the mixing section 30 being stopped. According to the invention it is provided that, as in 1 shown, exhaust 50 also outside at the mixing section 30 is bypassed. This can be a heating of the mixing section 30 can be achieved, thereby reducing the blocking elements 31 impinging droplets of the fluid 51 can be evaporated particularly effectively. This can also be a mixing of the fluid 51 in the exhaust 50 be further improved. So that this flow past the exhaust gas 50 at the mixing section 30 can be ensured, can be provided in particular that an outer wall 33 of the mixing section 30 from an inner wall 74 of the tubular element 71 spaced apart can be arranged, with a bypass gap 34 forms (not shown). After the mixing section 30 is a second lead 40 arranged. This second lead section 40 also has inlet openings 41 and guiding elements 42 on. This also allows the exhaust gas 50 inside the mixer element 1 be initiated, which is due to the arrangement of the guide elements 42 also in the second lead section 40 a circular turbulence of the exhaust gas 50 results. In particular, it can preferably be provided that the entry directions 62 in which the exhaust 50 through the first lead section 20 or the second guide section 40 inside the mixer element 1 be guided, at least substantially the same. The through the lead sections 20 . 40 created turbulence in the Interior of the mixer element 1 can thereby reinforce each other. An even more effective and better mixing of the exhaust gas 50 and the injected fluid 51 can be achieved. To complete the introduction of the mixing section 30 Passed exhaust gas 50 through the second guide section 40 can ensure the basic body 10 after the second lead section 40 a contact section 13 exhibit. This contact section 13 is in particular adapted to an inner wall 74 of the tubular element 71 (not shown with) form fit to contact and so the bypass gap 34 to end. In this way it can be ensured that no exhaust gas 50 completely at the mixer element 1 flowed past and so on the mixing with fluid 51 does not participate. Overall, by an inventive mixer element 1 an exhaust 50 and a fluid 51 to an exhaust gas-fluid mixture 52 be mixed, in particular a particularly good mixing, an effective evaporation of the fluid 51 and avoiding deposits of the fluid 51 in the mixer element 1 can be enabled. For example, with this mixer element 1 Mixing with an even distribution of the fluid 51 in the exhaust-fluid mixture 52 be achieved of more than 95%, while a pressure drop while flowing through the mixer element is minimized. Also, through the use of the circular turbulences, a velocity equal distribution of the exhaust gas-fluid mixture 52 in the general flow direction 60 be well above 90%.

4 shows a part of an exhaust line according to the invention 70 , In particular, a pipe element 71 shown in which a mixer element according to the invention 1 is arranged. The pipe element 71 is in particular U-shaped, wherein the mixer element 1 at a transition between a leg 73 and the base 72 of the U-shaped tubular element 71 is arranged. At the upper end of the tubular element 71 is also an injection element 75 arranged. Between an outer wall 33 of the mixing section 30 of the mixer element 1 and an inner wall 74 of the tubular element 71 This forms a bypass gap 34 , This allows a passage of a part of the exhaust gas 50 (not shown) at the mixing section 30 , whereby this can be heated. A particularly good evaporation of the injected fluid 51 (not shown) can be made possible. By a flow element 76 that has a free flow cross-section of the tubular element 71 and the bypass gap 34 covers, a direction of flow around the mixer element 1 through the exhaust 50 (not shown). It is also in the exhaust 50 generates a twist, which by the mixer element according to the invention 1 is further strengthened. A particularly good mixing of the exhaust gas 50 with the through the injection element 75 injected fluid 51 (not shown) can be achieved. Particularly preferably, it can be provided that the tubular element 71 is arranged between a catalyst and an SCR particulate filter. In this way it can be made possible that already pre-cleaned exhaust gas 50 in the pipe element 71 is initiated. In the pipe element 71 , And in particular in the mixing element arranged therein 1 , the exhaust becomes 50 with a fluid 51 , in particular with ammonia or urea, mixed, and then fed to the SCR particulate filter. By mixing the ammonia or urea in the SCR particulate filter, a selective removal of nitrogen oxides from the exhaust gas 50 respectively. A particularly good cleaning of the exhaust gas 50 can be provided thereby.

In the 5 and 6 are two different sectional views of a part of an embodiment of a Abgasstranges invention 70 , in particular a tubular element 71 with a mixer element according to the invention arranged therein 1 , shown. The two figures will be described together below. It is in 5 the pipe element 71 in a perspective sectional view, in 6 shown in a sectional view in a plan view. The mixer element 1 that in the pipe element 71 is arranged, has a first guide section 20 , a mixing section 30 and a second guide section 40 on that in a body 10 of the mixer element 1 are arranged. In this case, have the leading sections 20 . 40 each inlet openings 21 . 41 on, in particular by notching of guide elements 22 . 42 are formed. In the 5 . 6 are exemplified only one of the inlet openings 21 . 41 or one of the guiding elements 22 . 42 provided with a reference numeral. exhaust 50 flows in a flow direction 60 in the pipe element 71 and through the inlet openings 21 . 41 in an entry direction 62 inside the mixer element 1 , represented in particular in 6 , By blocking elements 31 of the mixing section 30 of which one is exemplified by a reference numeral and the one in a flow direction 61 (not shown) a blocking area 32 form, on the one hand, a mixing of the exhaust gas 50 with an injected fluid 51 (not shown with) supported and on the other hand, a penetration of the mixer element 1 through the injected fluid 51 prevented. Furthermore, while the mixer element 1 such in the tubular element 71 arranged that between an inner wall 74 of the tubular element and an outer wall 33 of the basic body 10 a bypass gap 34 forms. The exhaust 50 thus can the mixer element 1 flow around, causing, for example, a heating of the mixer element 1 and thus an improved evaporation of the into the exhaust gas 50 injected fluid 51 can be improved. Furthermore, in the pipe element 71 a flow element 76 arranged. In particular in 5 is clearly visible that this flow element 76 a part, in particular a half, of a free flow cross-section of the tubular element 71 covers. In addition, through the flow element 76 also the bypass gap 34 covered. A flow of the exhaust gas 50 in or through these covered areas is in this way by the flow element 76 prevented. This can cause the exhaust gas 50 , as in 6 represented by arrows, the mixer element 1 only flow around in one direction, causing in the exhaust 50 a twist is generated. This twist is caused by the configuration of, for example, the inlet openings 21 . 41 , the guiding elements 22 . 42 and the blocking elements 31 further strengthened. An even better thorough mixing of the exhaust gas 50 with the injected fluid 51 can be provided thereby.

In an alternative embodiment, the mixer element is 1 in the first guide section 20 not cylindrical, but tapered, the diameter increases to the mixing section 30 out. In this way, the flow can favor certain types and thus reduce pressure losses. The cone angle is preferably in the range of 1 ° to 30 °, particularly preferably in the range of 5 ° to 30 °.

LIST OF REFERENCE NUMBERS

1

mixer element

10

body

11

Injection port

12

mounting portion

13

Contact section

20

first leading section

21

inlet opening

22

vane

30

mixing section

31

blocking element

32

blocking surface

33

outer wall

34

bypass gap

40

second lead section

41

inlet opening

42

vane

50

exhaust

51

fluid

52

Exhaust fluid mixture

60

flow direction

61

Flow direction

62

entry direction

70

exhaust gas line

71

tube element

72

Base

73

leg

74

inner wall

75

Injector

76

flow element

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• US 2014/033686 A1 [0002]

Claims (15)

Mixer element ( 1 ) for mixing in a fluid ( 51 ) into an exhaust gas ( 50 ) of an internal combustion engine, wherein the mixer element ( 1 ) in an exhaust gas line ( 70 ) of the internal combustion engine can be arranged, comprising a first guide section ( 20 ) for generating a turbulence of the exhaust gas ( 50 ) and a mixing section ( 30 ) for mixing the injected fluid ( 51 ) with the swirling exhaust gas ( 50 ) to an exhaust gas-fluid mixture ( 52 ), wherein with respect to a flow direction ( 60 ) of the exhaust gas ( 50 ) the first lead ( 20 ) before the mixing section ( 30 ) is arranged, and further wherein the mixer element ( 1 ) a second lead ( 40 ) for mixing in at the mixing section ( 30 ) passing exhaust gas ( 50 ) into the exhaust gas-fluid mixture ( 52 ), wherein the second guide section ( 40 ) with respect to the flow direction ( 60 ) of the exhaust gas ( 50 ) after the mixing section ( 30 ) is arranged. Mixer element ( 1 ) according to claim 1, characterized in that the mixer element ( 1 ) a basic body ( 10 ), wherein the first guide section ( 20 ), the mixing section ( 30 ) and the second lead section ( 40 ) directly adjacent to one another and / or in the main body ( 10 ) are arranged, in particular the main body ( 10 ), the first lead ( 20 ), the mixing section ( 30 ) and the second lead section ( 40 ) are integrally formed. Mixer element ( 1 ) according to claim 2, characterized in that the basic body ( 10 ) an injection opening ( 11 ), through which into the interior of the mixer element ( 1 ) the fluid ( 51 ) is injectable, wherein the injection opening ( 11 ) with respect to the flow direction ( 60 ) before the first phase ( 20 ) is arranged. Mixer element ( 1 ) according to one of the preceding claims, characterized in that the first guide section ( 20 ) and / or the second lead section ( 40 ) Guiding elements ( 22 . 42 ), in particular baffles, for conducting the exhaust gas ( 50 ) into the interior of the mixer element ( 1 ) exhibit. Mixer element ( 1 ) according to claim 4, characterized in that the first guide section ( 20 ) and / or the second lead section ( 40 ) Inlet openings ( 21 . 41 ) for a radial inlet of the exhaust gas ( 50 ) in the interior of the guide sections, wherein the guide elements ( 22 . 42 ) for passing the exhaust gas ( 50 ) into the interior of the guide sections at the inlet openings ( 21 . 41 ) are arranged. Mixer element ( 1 ) according to claim 5, characterized in that the guide elements ( 22 ) of the first section ( 20 ) and the guiding elements ( 42 ) of the second guidance section ( 40 ) the exhaust gas ( 50 ) in an at least substantially identical direction of entry ( 62 ) into the interior of the first guidance section ( 20 ) and the second guidance section ( 40 ) conduct. Mixer element ( 1 ) according to one of the preceding claims, characterized in that the mixing section ( 30 ) Blocking elements ( 31 ), in particular scoop-like blocking elements ( 31 ), with a blocking surface ( 32 ), wherein the blocking surface ( 32 ) with a rectilinear flow direction ( 61 ) has an acute angle. Mixer element ( 1 ) according to claim 7, characterized in that the blocking elements ( 31 ) with respect to the rectilinear flow direction ( 61 ) at least partially overlap. Mixer element ( 1 ) according to one of the preceding claims, characterized in that the mixer element ( 1 ) at least one mounting section ( 12 ) for mounting in a mounting position in a tubular element ( 71 ) of the exhaust gas line ( 70 ), wherein in the mounting position between an outer wall ( 33 ) of the mixing section ( 30 ) and an inner wall ( 74 ) of the tubular element ( 71 ) a bypass gap ( 34 ) is trained. Exhaust line ( 70 ) for an internal combustion engine, comprising an injection element ( 75 ), a tubular element ( 71 ) and a mixer element ( 1 ), wherein the mixer element ( 1 ) in the tubular element ( 71 ), characterized in that the mixer element ( 1 ) is designed according to one of the preceding claims. Exhaust line ( 70 ) according to claim 10, characterized in that in the tubular element ( 71 ) at least between an outer wall ( 33 ) of the mixing section ( 30 ) of the mixer element ( 1 ) and an inner wall ( 74 ) of the tubular element ( 71 ) a bypass gap ( 34 ), in particular a circumferential annular gap, is formed. Exhaust line ( 70 ) according to claim 11, characterized in that in the tubular element ( 71 ) and / or on the mixer element ( 1 ) a flow element ( 76 ), wherein the flow element ( 76 ) a portion of a free flow cross section of the tubular element ( 71 ) and the bypass gap ( 34 ) for generating a directed flow around the mixer element ( 1 ) with exhaust gas ( 50 ) covers. Exhaust line ( 70 ) according to claim 11 or 12, characterized in that on the mixer element ( 1 ) with respect to the flow direction ( 60 ) of the exhaust gas ( 50 ) after the second phase ( 40 ) a contact section ( 13 ), wherein the bypass gap ( 34 ) by a positive contact of the contact portion ( 13 ) on the inner wall ( 74 ) of the tubular element ( 71 ) ends. Exhaust line ( 70 ) according to claim 10 to 13, characterized in that the tubular element ( 71 ) substantially U-shaped with two legs ( 73 ) and a base ( 72 ), wherein in particular the mixing element ( 1 ) at a transition between a leg ( 73 ) and the base ( 72 ) is arranged. Exhaust line ( 70 ) according to one of the preceding claims 10 to 14, characterized in that the exhaust gas line ( 70 ) comprises a catalyst and an SCR particulate filter, wherein the tubular element ( 71 ) with the mixing element arranged therein ( 1 ) is disposed between the catalyst and the SCR particulate filter.

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