CN120641641A

CN120641641A - Burner for an exhaust gas system of a motor vehicle, in particular an internal combustion engine of a motor vehicle

Info

Publication number: CN120641641A
Application number: CN202480011089.3A
Authority: CN
Inventors: A·冯盖斯伯格-海芬伯格; T·希尔特; J·黑夫纳; T·斯托尔克; U·艾斯曼; A·沃特迈尔; H·策勒
Original assignee: Mercedes Benz Group AG
Current assignee: Mercedes Benz Group AG
Priority date: 2023-02-08
Filing date: 2024-02-02
Publication date: 2025-09-12
Also published as: WO2024165427A1; DE102023000389B3

Abstract

The invention relates to a burner (18) for an exhaust system (10) of an internal combustion engine, comprising a combustion chamber (22) formed by a chamber element (20) of the burner (18), in which a mixture of air as a first fluid and fuel as a second fluid is ignited and thus burns, whereby components of the exhaust system (10), in particular exhaust gas aftertreatment elements and/or exhaust gases of the internal combustion engine flowing through the exhaust system (10), can be heated, and a channel (42) through which at least one of the fluids can flow and which leads to the combustion chamber. The invention relates to a combustion chamber (22), wherein at least one fluid can be introduced into the combustion chamber (22) through the channel, and has a closing element (52) which is movable relative to the chamber element (20) between a closed position (S) separating the channel (42) from the combustion chamber (22) fluid and at least one release position (F) connecting the channel (42) to the combustion chamber (22) fluid, wherein the chamber element (20) has a recess (54) in which the closing element (52) is at least partially accommodated in the release position (F).

Description

Burner for an exhaust gas system of a motor vehicle, in particular an internal combustion engine of a motor vehicle

Technical Field

The present invention relates to a burner for an exhaust gas system of an internal combustion engine according to the preamble of claim 1. The invention also relates to an internal combustion engine having at least one such burner.

Background

DE 10 2021 001 580A1 discloses a burner for an exhaust gas passage through which exhaust gas of an internal combustion engine of a motor vehicle can flow, which burner has a combustion chamber in which a mixture comprising air and liquid fuel is to be ignited and thus burnt.

Disclosure of Invention

The object of the present invention is to provide a burner for an exhaust gas system of an internal combustion engine and an internal combustion engine having at least one such burner, such that a particularly advantageous operation of the burner can be achieved.

This object is achieved by a burner having the features of claim 1 and an internal combustion engine having the features of claim 10. Advantageous embodiments with suitable developments of the invention are given in the remaining claims.

A first aspect of the invention relates to a burner for an exhaust gas system, also called exhaust gas channel, of an internal combustion engine, also called engine or engine, and configured for example as a reciprocating piston engine, whereby the internal combustion engine is configured as a reciprocating piston engine, in particular of a motor vehicle. This means that a motor vehicle, which is also referred to simply as a vehicle and is preferably configured as a motor vehicle, in particular a passenger vehicle or a commercial vehicle, has an internal combustion engine in its fully manufactured state and can be driven by the internal combustion engine. In particular, internal combustion engines are configured, for example, as diesel engines. During a combustion operation of the internal combustion engine, a combustion process takes place in the internal combustion engine, in particular in at least one or more combustion chambers of the internal combustion engine, whereby exhaust gases of the internal combustion engine are produced. The exhaust gases produced by the combustion process of an internal combustion engine are also referred to as engine exhaust gases. If the exhaust gases mentioned above and below refer to engine exhaust gases, unless otherwise indicated. The exhaust gas may flow out of the respective combustion chamber and into the exhaust system and then through the exhaust system. At least one component, such as an exhaust gas aftertreatment element for aftertreatment of the exhaust gas, may be arranged in the exhaust gas system. The exhaust gas aftertreatment element is or comprises, for example, a catalyst, in particular an SCR catalyst, wherein Selective Catalytic Reduction (SCR) can be carried out, for example, by means of the SCR catalyst for catalytic support and/or such that, for example, the SCR catalyst has catalytic activity for SCR. In Selective Catalytic Reduction (SCR), nitrogen oxides (NOx) that may be present in the exhaust gas are at least partially removed from the exhaust gas, because in selective catalytic reduction nitrogen oxides react with ammonia to form nitrogen and water. Ammonia is provided, for example, by a liquid reducing agent in particular. The liquid reducing agent is in particular an aqueous urea solution. Furthermore, the exhaust gas aftertreatment element may be or comprise a particle filter, in particular a diesel particle filter, wherein particles, in particular soot particles, which may be contained in the exhaust gas, may be filtered out of the exhaust gas by the particle filter.

The burner has a chamber element, which is preferably configured as a solid, and a combustion chamber, which is formed by the chamber element, in particular is defined by the chamber element. In particular, the combustion chamber is defined, for example, by a cladding surface on the inner circumferential side of the chamber element, in particular directly. In the combustion chamber, a mixture, also called burner mixture, comprising air, also called burner air, and preferably a liquid fuel, can be ignited and thus burnt. The combustion of the burner mixture, in particular in the combustion chamber, generates, for example, burner exhaust gases, also called burner exhaust gases, in particular in the combustion chamber. The burner exhaust gas may for example flow out of the combustion chamber into the exhaust system, i.e. for example into an exhaust gas channel of the exhaust gas system through which the engine exhaust gas may flow, in particular at an introduction point arranged upstream of the aforementioned components, for example in the flow direction of the engine exhaust gas flowing through the exhaust gas channel. For example, the burner exhaust gas may be mixed with the engine exhaust gas, in particular in the exhaust gas channel. Thus, the burner exhaust gas, in particular the burner exhaust gas mixed with the engine exhaust gas, may for example flow through the component, as a result of which the component may be heated, i.e. warmed and/or kept warm. The air forming the burner mixture with the preferably liquid fuel is also referred to as burner air. The internal combustion engine is operated in its combustion operation, for example by means of in particular liquid fuel. In particular, when the internal combustion engine is configured as a diesel engine, the fuel may be diesel fuel. In this case, it has proved to be particularly advantageous if fuel oil is used as fuel.

The burner air is the first fluid, or also referred to as the first fluid. The fuel is a second fluid, or also referred to as a second fluid. As the burner mixture is ignited and burned, components of the exhaust system, in particular the exhaust aftertreatment element and/or the engine exhaust gas flowing through the exhaust system, may be heated. The component may be indirectly heated or warmed by the heated engine exhaust.

For example, the burner has an ignition element, in particular an electrically operable ignition element, which for example passes through a through hole of the chamber element, so as to protrude for example into the combustion chamber. It is thus particularly conceivable for the ignition element to be arranged at least partially in the combustion chamber, in particular in such a way that one end, in particular the free end, of the ignition element is arranged in the combustion chamber so as to protrude into the combustion chamber. The burner mixture, in particular in the combustion chamber, can be ignited by means of an ignition element. For example, at least one ignition spark for igniting the burner mixture can be provided, i.e. generated, by means of an ignition element, in particular in the combustion chamber and/or by using electrical energy, such that the burner mixture in the combustion chamber can be ignited by the ignition spark. The ignition element may be, for example, a glow plug or a spark plug.

The burner also has at least one passage through which at least one fluid can flow, which passage itself, i.e. viewed separately, leads to the combustion chamber. For this purpose, the channel has, for example, at least one or exactly one outlet opening through which the channel itself, i.e. when viewed separately, opens into the combustion chamber. Thus, in particular during operation of the burner, at least one fluid may flow through the channel, in particular the outlet opening of the channel, so as to flow out of the channel via the outlet opening, and in particular directly into the combustion chamber. It is conceivable that the line element and thus the outlet opening with respect to the fluid can be flowed through by exactly one fluid, so that, for example, after one fluid has flowed out of the channel, the other fluid is supplied to or mixed with the one fluid. Furthermore, it is conceivable that both fluids may flow through the channel and thus through the outlet opening. Thus, both fluids may be introduced into the combustion chamber, for example, through a channel. The channel is also referred to as a line element, or the channel is for example defined by a line element, in particular directly, the line element being in particular in solid form. In this case, it is particularly conceivable that the channel is defined by a cladding surface on the inner circumferential side of the line element, in particular directly.

The burner also has a closing element which is movable relative to the chamber element, which is preferably configured as a solid, between a closed position, which fluidly separates the channel from the combustion chamber, and at least one release position, which fluidly connects the channel with the combustion chamber. This means that in the closed position the channel is fluidly separated from the combustion chamber by the closing element, so that in the closed position no or only little fluid, i.e. in particular no fluid, can flow out of the pipe element and into the combustion chamber. The closed position is particularly advantageous because in the closed position no gas, such as engine exhaust gas, can penetrate from the combustion chamber into the channel. At a minimum, the closed position prevents particles that may be contained in engine exhaust from entering the passage. For example, the combustion chamber is fluidly connected to the exhaust passage. For example, if the burner is deactivated such that the burner does not provide burner exhaust gas, at least a portion of the engine exhaust gas flowing through the exhaust gas passage may, for example, flow into the combustion chamber, thereby penetrating or penetrating forward/into the combustion chamber. Since the closing element is now in the closed position, in particular when the burner is inactive, as a result of which the channel is fluidly separated from the combustion chamber, the engine exhaust gas flowing into the combustion chamber cannot penetrate from the combustion chamber into the channel, so that the engine exhaust gas or particles possibly contained therein cannot penetrate from the exhaust gas channel into undesired areas, such as the burner. The burner has, for example, an introduction element by means of which, in particular, liquid fuel can be introduced, in particular injected, into the burner air, in particular at an introduction point which can be arranged upstream of the combustion chamber, in particular upstream of the outlet opening, in the flow direction of the burner air flowing through the combustion chamber. Furthermore, the burner has an air channel through which, for example, burner air can flow, which extends, for example, upstream of the outlet opening. Since now, in particular when the burner is inactive or during the burner is inactive, the closing element is in the closed position, as a result of which the channel is fluidly separated from the combustion chamber, for example, no engine exhaust gases can penetrate from the combustion chamber into the air channel and/or into the introduction element, so that the air channel and/or the introduction element can be protected from engine exhaust gases or in particular when the burner is inactive or during the burner is inactive.

In order to be able to achieve particularly advantageous operation of the burner, according to the invention, it is provided that the chamber element, in particular on or on its inner side facing the combustion chamber, has a recess, also called a pocket, in which the closure element is at least partially, in particular at least predominantly, and thus at least more than half or completely accommodated in the release position. As a result, in the release position of the closure element, a particularly flow-favorable contour, in particular an inner contour, of the combustion chamber can be ensured, so that particularly effective operation of the burner can be achieved. In particular, by means of the invention, excessive damage to the flow occurring in the combustion chamber, in particular to the burner air and/or the burner mixture, by the closing element can be avoided, so that a particularly efficient operation of the burner can be achieved. Furthermore, in the release position, for example, the closing element can be protected from excessive inflow of burner exhaust gases or excessive flow around the burner exhaust gases.

It is thus provided that in the release position at least one sub-region, in particular at least one main sub-region, also called arrangement region, of the closure element is arranged in the recess, wherein, for example, in the closed position, the arrangement region is arranged outside the recess, in particular in the combustion chamber. Furthermore, it is conceivable, for example, for at least a part, in particular at least a major part, of the storage area, and thus at least more than half, to be arranged outside the recess, in particular in the combustion chamber, in the closed position, with respect to the entire area of the closure element, also called storage area, in the release position provided in the recess. The storage area may be the entire closure element.

The invention is based on the discovery and consideration, inter alia, that internal combustion engines, in particular for motor vehicles, are generally equipped with corresponding exhaust gas aftertreatment devices. By means of a respective exhaust gas aftertreatment device, an exhaust gas aftertreatment can be performed, by means of which or in which a respective exhaust gas from a respective internal combustion engine is aftertreatment. The purpose of the exhaust gas aftertreatment may be in particular to reduce or eliminate pollutants, such as nitrogen oxides, which may be present in the exhaust gas. In order to be able to realize the advantageous functions of the exhaust gas aftertreatment device, and thus of the aforementioned exhaust gas aftertreatment element, a minimum operating temperature of the exhaust gas aftertreatment device is generally required. The internal combustion engine may have an operating region in which heating the exhaust gas aftertreatment device by the engine exhaust gas alone is insufficient to heat the exhaust gas aftertreatment device to at least an operating temperature, or the exhaust gas aftertreatment device is not sufficiently fast to heat to an operating temperature, for example during a cold start of the gasoline engine. By means of the burner, the exhaust gas aftertreatment device can be additionally heated. In operating areas where the burner is not required and is therefore deactivated, it is preferable to ensure that the components of the burner are protected from contamination, for example. The components of the burner may be protected in particular in such a way that the channel is fluidly separated from the combustion chamber by the closing element in the closed position, as previously described. Before activation, i.e. before the initially deactivated burner is activated, for example, the closure element is moved, in particular pivoted, relative to the chamber element from the closed position to the release position, in particular in such a way that the closure element is moved, in particular pivoted, away from the channel, in particular away from the outlet opening. For example, if in the release position an excessive portion of the closure element is arranged in the combustion chamber such that the excessive portion of the closure element stands freely in the combustion chamber in the release position, intense heating of the closure element may occur, in particular until the closure element has a temperature corresponding to the temperature of the fuel gas surrounding the closure element. The fuel gas is in particular burner exhaust gas. Thus, it may be necessary to manufacture the closure element from expensive heat resistant steel and possibly high nickel steel. Furthermore, when an excessive portion of the closure element in the release position stands freely in the combustion chamber, the flow of, for example, mixture and/or burner exhaust gases may be hindered. This involves both radial flow of expanding fuel gas flowing from the center of the combustion chamber (also referred to as the combustion chamber) in the direction of the downstream components, and free flow of burner air (also referred to as combustion air) into the combustion chamber from a passage also referred to as the feed line. As a result, excessive amounts of soot/soot may be generated during burner operation, which may lead to undesirable emissions if appropriate countermeasures are not taken.

The above-described disadvantages can now be avoided in that in the release position the closure element is at least partially, in particular at least mainly or completely, accommodated in the recess.

For example, the combustion chamber, in particular on the inner circumferential side, is configured to be at least substantially rotationally symmetrical, wherein, for example, the chamber element and thus the combustion chamber have, for example, grooves that are at least substantially rotationally symmetrical. In particular, it is conceivable that the recess is integrally formed as at least a rotationally symmetrical pocket on the chamber element and the combustion chamber. The closure element is at least partially immersed in the recess if the closure element is moved relative to the chamber element from the closed position to the release position. Preferably, in the release position the closing element is arranged so much or even completely in the recess that at least almost no rotationally symmetrical inner space of the combustion chamber remains empty, wherein said inner space is configured or can be used as a combustion volume. It is particularly preferred that the closure element is immersed in the recess such that the side facing away from the combustion chamber is immediately adjacent to the outer wall of the recess. In particular, the invention achieves at least the advantage that the closure element absorbs only a small amount of combustion heat, since in the release position the closure element is not excessively free in the combustion chamber. For example, the closure element may release at least a portion of the absorbed combustion heat back into the environment through the outer wall. Thus, excessive temperatures of the closure element can be avoided, so that the closure element can be produced, for example, inexpensively. Since the closing element is immersed in the recess and thus accommodated in the recess in the release position, an at least almost rotationally symmetrical region without interfering contours can be produced in the release position, wherein said region is free of the closing element and is at least part of the combustion chamber. Then, in this at least almost rotationally symmetrical region, particularly advantageous swirling flows, in particular of the burner mixture and/or of the burner air, can be formed, which are advantageous for low soot/soot and efficient combustion. Thus, a particularly efficient operation of the burner may be achieved.

In order to enable a particularly efficient and thus particularly advantageous operation of the burner, in one embodiment of the invention, at least one first subregion of the cladding surface facing the outer circumferential side of the closure element of the combustion chamber in the release position and at least one second subregion of the cladding surface facing the combustion chamber in the release position opposite the first subregion and facing the combustion chamber in the release position, in particular facing the inner space or region, and the inner circumferential side of the chamber element of the first subregion form a rotationally symmetrical region of the combustion chamber, also referred to as combustion chamber region. The combustion chamber region is in particular completely free of closing elements, so that a particularly advantageous flow, in particular in the form of a swirl, in particular a flow of the burner mixture and/or of the burner air, can be formed in the combustion chamber region.

A further embodiment is characterized in that in the release position, at least one first subregion of the cladding surface on the outer circumferential side of the closure element facing the combustion chamber in the release position and at least one second subregion of the cladding surface on the inner circumferential side of the chamber element facing the combustion chamber and the first subregion in the release position opposite the first subregion form a mirror-symmetrical region, also referred to as combustion chamber region, with respect to at least one plane of symmetry of the combustion chamber. For example, the first portion of the cladding surface on the outer circumferential side may be a first sub-region of the cladding surface on the outer circumferential side. Furthermore, it is conceivable that the second portion of the cladding surface on the inner circumference side is a second sub-region of the cladding surface on the inner circumference side. Furthermore, it is conceivable that the chamber region is the combustion chamber region described above. In this case, it is also provided that the straight line extends in the plane of symmetry, which extends through the outlet opening of the channel, which opens into the combustion chamber via its outlet opening, in particular in such a way that the straight line passes through the centre of the outlet opening. For example, the outlet opening is circular, thus in the form of a circle, the centre of which coincides with, for example, said centre of the outlet opening and lies on said straight line. As a result, a particularly advantageous flow, in particular in the form of a swirl, in particular a flow of the burner mixture and/or of the burner air can be formed in the chamber region, so that a particularly efficient operation of the burner can be achieved.

In a further particularly advantageous embodiment of the invention, it is provided that the closure element in the release position is arranged at least predominantly, i.e. at least more than half or completely, in the recess. Thus, overheating of the closure element can be avoided and conditions particularly favorable for flow can be created in the combustion chamber. Thus, a particularly efficient operation of the burner can be ensured.

A further embodiment is characterized in that the closing element is pivotable relative to the chamber element about a pivot axis between a release position and a closed position. In this case, the closure element has, for example, a lever which is pivotable relative to the chamber element about a pivot axis between a release position (also referred to as an open position) and a closed position, and a closure portion which is also referred to as a cover or flap/plate, a closure flap/plate or a closure cap. The closing portion is configured separately from the lever and is held on the lever, whereby the closing portion can be pivoted together with the lever about a pivot axis relative to the chamber element between the release position and the closed position.

In the closed position, the closing portion covers the outlet opening of the channel, whereby the channel is fluidly separated from the combustion chamber or at least covered. In the release position, the closure portion releases the outlet opening, whereby the channel is fluidly connected to the combustion chamber through the outlet opening. In particular, the closing portion in the release position does not overlap the outlet opening. In this way, a particularly safe and thus robust movement of the closure element between the release position and the closed position can be achieved, so that a particularly advantageous operation of the burner can be achieved.

In this case, it has proved to be particularly advantageous if the pivot axis passes through the recess. As a result, the closing element can be accommodated to a very large extent, i.e. a very large part or even completely, in the recess, so that particularly advantageous operation of the burner can be ensured.

A further embodiment is characterized in that the closing part is held with play on the lever so as to move in a limited manner relative to the lever. In other words, the lever and the closing portion are constructed in a plurality of parts, i.e., separated from each other, with a certain gap therebetween, i.e., maintained with each other. As a result, for example, when the closing element is moved into the closed position, the closing portion can lie flush and/or tightly against the line element, in particular against the end face of the line element facing the combustion chamber, so as to reliably close the outlet opening, for example be configured as a hole, so as to seal or at least cover the outlet opening.

The lever and the closure part held thereon form, for example, a lever mechanism which is accommodated in a flow-facilitating manner in a groove called recess in the release position. In particular, the lever mechanism may be accommodated in the recess without undercuts, sharp edges or abrupt transitions in the release position. The closing element, in particular the lever mechanism, is in particular designed to ensure good heat transfer between the closing element and the chamber element (also called housing). For this purpose, for example, a bulky design of the closure element is provided in order to be able to ensure an advantageous heat transfer. The recess (also called pocket) of the chamber element is preferably designed such that only a small gap, in particular the contour, in particular the inner contour, of the recess is created between the closure element and the recess. For example, the recess has the same contour, in particular an inner contour, as the contour, in particular an outer contour, of the closure element, wherein, for example, the inner contour of the recess increases only the gap for thermal expansion of the closure element relative to the outer contour of the closure element. Alternatively or additionally, for example, the closing element, in particular the lever, has, on its combustion chamber side in the release position, the same or at least a similar radius as the combustion chamber, so that a flow-facilitating arrangement can be presented.

In a further particularly advantageous embodiment of the invention, it is provided that the inner contour of the recess facing the closure element in the release position matches the outer contour of the closure element facing the inner contour in the release position. As a result, the closing element can be accommodated in the recess to a particularly great extent or even completely, whereby a flow-favorable shape, in particular an inner contour, of the combustion chamber can be ensured.

Finally, it has proven to be particularly advantageous if the wall region of the at least one adjoining recess of the chamber element is flush with the closure element in the release position. As a result, flow-favorable conditions can be achieved in the combustion chamber, so that efficient operation of the burner can be achieved.

A second aspect of the invention relates to an internal combustion engine having at least one burner according to the first aspect of the invention. The advantages and advantageous embodiments of the burner according to the invention should be regarded as those of the internal combustion engine according to the invention and vice versa.

Drawings

Further advantages, features and details of the invention are given in the following description of preferred embodiments and with reference to the drawings. The features and combinations of features mentioned in the description and the features and combinations of features mentioned in the description of the figures and/or shown in the figures alone may be used not only in the respective combination but also in other combinations or alone without departing from the scope of the invention.

In the figure:

Fig. 1 shows a part of a schematic cross-section of an internal combustion engine of a motor vehicle with a burner, wherein a closure element of the burner is in a release position;

FIG. 2 shows a schematic cross-sectional view of the internal combustion engine along the section line A-A shown in FIG. 1, and

Fig. 3 shows a part of a further schematic sectional view of an internal combustion engine, with the closure element in the closed position.

In the drawings, elements having the same reference number are identical or functionally identical.

Detailed Description

Fig. 1 shows an internal combustion engine of a motor vehicle in a part of a schematic sectional view. In particular, fig. 1 shows in part an exhaust system 10, also referred to as an exhaust gas passage, of an internal combustion engine. The exhaust system has an exhaust gas line element 12 with an exhaust gas duct 14, in particular a limited, in particular directly defined duct. The internal combustion engine may be operated in a combustion operation. During its combustion operation, the internal combustion engine provides exhaust gas, also referred to as engine exhaust gas, which may flow through the exhaust passage 14. In fig. 1, arrow 16 shows engine exhaust gas flowing through exhaust passage 14. The internal combustion engine has a burner 18 arranged in the exhaust gas system 10, by means of which burner 18 the engine exhaust gas and/or components of the exhaust gas system 10 can be heated. For this purpose, the burner 18 has a chamber element 20, which is designed in particular as a solid body, and a combustion chamber 22, which is formed by the chamber element 20, in particular defined by the chamber element 20. In particular, the combustion chamber 22 is defined, in particular directly defined, by a cladding surface 24 on the inner circumferential side of the chamber element 20. In the combustion chamber 22, a mixture, also referred to as a burner mixture, may be ignited and thus burned. The burner mixture includes air, also referred to as burner air. In addition, the burner air is also referred to as the first fluid. Furthermore, the burner mixture comprises in particular a liquid fuel, also called second fluid. Ignition and combustion of the burner mixture produces an exhaust gas of the burner 18, also referred to as burner exhaust gas, wherein the burner exhaust gas is shown by arrow 26 in fig. 1. It can be seen that the chamber element 20 has through-flow openings 28, through which openings 28 the combustion chamber 22 is fluidly connected to the exhaust gas channel 14. The burner exhaust gas may flow through the through-flow opening 28 to exit the combustion chamber 22 at the introduction point E and flow into the exhaust passage 14, whereby the burner exhaust gas is introduced into the engine exhaust gas. As a result, the engine exhaust gas is heated, or a total exhaust gas is formed comprising the engine exhaust gas and the burner exhaust gas, which may flow through the exhaust system 10, in particular the exhaust gas channel 14, from the introduction point E. This is indicated by arrow 30. For example, at least one exhaust gas aftertreatment element is arranged in the exhaust gas system 10 downstream of the introduction point E, by means of which the engine exhaust gas and the burner exhaust gas can be aftertreatment. The exhaust gas aftertreatment element can be warmed up and/or kept warm by heating the engine exhaust gas or the hot total exhaust gas or the burner exhaust gas, as a result of which, for example, the exhaust gas aftertreatment element can reach its operating or starting temperature, also referred to as the ignition temperature, particularly rapidly.

An air supply 32 is provided, by means of which air supply 32 the burner 18, in particular the combustion chamber 22, can be supplied with burner air. For this purpose, the air supply 32 has an air channel 34 through which the burner air can flow. Arrows 36 illustrate the flow of burner air through the air passage 34. The air duct 34 is formed, for example, by a component 38 of the burner 18, which is configured in particular as a solid. The air supply 32 may have an air line, not shown in the figures, through which the burner air may flow. For example, the air line is configured separately from the member 38 and mechanically connected to the member 38, wherein the air line is fluidly connected to the air passage 34. As a result, the burner air flowing through the air line can flow out of the air line and into the air channel 34 and then through the air channel 34, so that, for example, the burner air can be supplied to the combustion chamber 22, i.e. introduced into the combustion chamber 22, in particular by means of the air channel 34. In particular, it is conceivable that the air line is mechanically connected to the component 38 by means of a V-belt clip, as a result of which a particularly simple and thus time-and cost-effective assembly can be achieved.

The burner 18 also has an introduction element 40, by means of which introduction element 40 fuel can be introduced, in particular injected into the burner air at the point of introduction/introduction. In particular, the introduction point is arranged upstream of the combustion chamber 22 in the flow direction of the burner air flowing through the burner 18, and thus outside the combustion chamber 22. The burner air is also referred to as the first fluid. The fuel is also referred to as the second fluid.

The burner 18, and in particular the member 38, has a passage 42, for example, through which passage 42 at least one fluid may flow. In the embodiment shown in the figures, both fluids, i.e. fuel and burner air, may flow through the channel 42, in particular in such a way that a burner mixture comprising the fluids may flow through the channel 42.

In this case, the burner air may be introduced into the passage 42 from the air passage 34, so that the passage 42 may be supplied with the burner air flowing through the air passage 34 by means of the air passage 34. This means in particular that the air channel 34 is arranged or extends upstream of the channel 42 in the flow direction of the burner air flowing through the air channel 34 and the channel 42. Furthermore, the fuel can be introduced, in particular directly, by means of the introduction element 40, in particular injected into the channel 42, so that the channel 42 can be supplied with fuel by means of the introduction element 40. Thus, for example, an introduction point is arranged in the channel 42, wherein the introduction point is arranged upstream of the combustion chamber 22. Furthermore, as can be seen from fig. 1, the air channel 34 is arranged upstream of the combustion chamber 22 or extends upstream of the combustion chamber 22. The burner air and fuel may flow through the passages 42, particularly in a mixed state with each other, and flow into the combustion chamber 22 through the passages 42 to be introduced. To this end, the passage 42 has an outlet opening 44, through which outlet opening 44 the passage 42 opens into the combustion chamber 22.

For example, the outlet opening 44 is rotationally symmetrical with respect to the straight line 46. For example, the outlet opening 44 is circular, thus in the form of a circle centered on a straight line 46. The midpoint is also referred to as the center of the outlet opening 44, or the center of the outlet opening 44. Arrow 48 illustrates the fact that fuel is supplied to the introduction element 40.

In fig. 1, arrow 50 shows that the burner 18, and in particular a swirl generator (not shown in more detail) of the burner 18, generates a swirl of burner air in the combustion chamber 22, thereby generating a swirl of the burner mixture. This means that the burner air and thus the burner mixture flows in a swirling flow at least in the combustion chamber 22. Thus, the burner air and the fuel can be advantageously mixed with each other.

The burner 18 also has a closing element 52, which in the embodiment shown in the figures is configured as a lever mechanism. The closure element 52 is movable relative to the chamber element 20 between a release position F shown in fig. 1 and a closed position S shown in fig. 3. In the embodiment shown in the figures, the closure element 52 is pivotable relative to the chamber element 20 about a pivot axis SA between a closed position S and a release position F. In the closed position S, the passage 42 is fluidly separated from the combustion chamber 22 by the closure element 52 (fig. 3). In the release position F, the closure element 52 releases the outlet opening 44, thereby releasing the passage 42, such that in the release position F, the passage 42 is fluidly connected to the combustion chamber 22 (fig. 1) through its outlet opening 44.

In order to enable particularly advantageous operation of the burner 18, the chamber element 20, in particular the cladding surface 24 on the inner circumferential side of the chamber element 20, has a recess 54, also called a pocket, in the release position F the closure element 52 is at least partially, in particular at least predominantly, and therefore at least more than half or completely accommodated. This can be seen particularly clearly in fig. 2, wherein the burner 18 is shown in a schematic cross-sectional view along the sectional line A-A shown in fig. 1. It can be seen that, as a result of the closure element 52 being at least partially accommodated in the pocket in the release position F, a particularly flow-favorable region B, also referred to as the interior space, of the combustion chamber 22 can be achieved, in which region B a swirl flow can be particularly advantageously formed. In particular, region B is an at least substantially rotationally symmetric region of the combustion chamber 22. Alternatively or additionally, for example, the region B is an at least substantially mirror-symmetrical region of the combustion chamber 22, wherein the mirror-symmetrical region is mirror-symmetrical, i.e. axially symmetrical, with respect to the plane of symmetry, and wherein the straight line 46 extends in the plane of symmetry. The symmetry plane is denoted EB1 in fig. 2, wherein, for example, a second symmetry plane EB2 is also shown, wherein the straight line 46 extends therein, wherein, for example, the region B can also be mirror-symmetrical with respect to the symmetry plane EB2, i.e. axially symmetrical. As can be seen from fig. 1, for example, the region B in the release position F is formed, for example, by a first partial region TB1 of the closure element 52 and a second partial region TB2 of the outer circumferential side coating surface 24. The first sub-area TB1 is a first sub-area of the cladding surface 56 on the outer circumferential side of the closing element 52, and the second sub-area TB2 is a second sub-area of the cladding surface 24 on the inner circumferential side of the chamber element 20. In the release position F, the first subregion TB1 faces the cladding surface 56 of the outer circumferential side of the closure element 52 of the combustion chamber 22, in particular in such a way that in the release position F a part of the combustion chamber 22 is directly defined by the subregion TB1. In the release position F, the subregion TB2 is opposite the subregion TB1, wherein in the release position F the second subregion TB2 of the combustion chamber 22 faces the first subregion TB1. In particular, for example, the second portion of the combustion chamber 22 in the release position F is defined directly by the sub-zone TB 2. For example, the first sub-area TB1 is a first portion of the coating surface 56 on the outer circumferential side, and for example, the second sub-area TB2 is a second portion of the coating surface 24 on the inner circumferential side.

In the embodiment shown in the figures, the closure element 52 has a lever 58 pivotable about a pivot axis SA relative to the chamber element 20 between a closed position S and a release position F, and has a closure portion 60, also referred to as a flap or closure flap. The closing portion 60 is configured separately from the lever 58 and is held on the lever 58 such that the closing portion 60 can pivot together with the lever 58 about the pivot axis SA with respect to the chamber element 20 between the release position F and the closed position S. In the closed position S, the outlet opening 44 is covered by the closure portion 60, as a result of which the channel 42 is fluidly separated from the combustion chamber 22. In the release position F, the closure portion 60 releases the outlet opening 44 such that in the release position F, the closure portion 60 does not overlap the outlet opening 44. Thus, the passage 42 is fluidly connected to the combustion chamber 22 via the outlet opening 44. For example, the closure portion 60 is retained on the lever 58 in a limited movement. As a result, in the closed position S (fig. 3), the closing portion 60 can advantageously rest against the conduit element 62, in particular against the end face 64 of the conduit element 62 facing the combustion chamber 22, whereby the outlet opening 44 can advantageously be sealed off so as to be blocked by the fluid. The line element 62 is a solid body, wherein the channel 42 is defined by the line element 62, in particular by a coating surface 66 on the inner circumferential side of the line element 62, in particular directly. For example, the line element 62 is a member 38 or is integrally formed with the member 38. In other words, for example, the member 38 and the conduit element 62 are formed from a single piece. Furthermore, it is conceivable that the component 38 and the line element 62 are separate from each other and connected to each other.

Furthermore, it can be seen from fig. 1 and 3 that in the release position F, the wall region W of the chamber element 20 adjoining the recess 54 on both sides is flush with the closure element 52, in particular the coating surface 56 on its outer circumferential side, and very particularly with the subregion TB1, so that the region B can be configured particularly advantageously for flow.

Furthermore, it is provided that the inner contour of the recess 54 facing the closure element 52 in the release position F matches the outer contour of the closure element 52 facing the inner contour in the release position F, such that the inner contour and the outer contour have the same shape. In other words, the outer profile has a positive shape, wherein the inner profile has a negative shape adapted to or corresponding to the positive shape. For example, the outer contour facing the inner contour faces away from the sub-region TB1. Furthermore, as can be seen from fig. 1 to 3, in the release position F at least one sub-region (also referred to as arrangement region or storage region) of the closure element 52 is arranged in the recess 54. In relation to the entire arrangement area of the closure element 52 arranged in the release position F in the recess 54, in the closed position S at least a part, in this case the main part, and thus more than half, of the arrangement area arranged in the release position F in the recess 54 is arranged outside the recess 54, in particular in the combustion chamber 22.

List of reference numerals

10 Exhaust gas system

12 Exhaust gas line element

14 Exhaust gas passage

16 Arrow head

18 Burner

20 Chamber element

22 Combustion chamber

24 Inner circumferential side coating surface

26 Arrow

28 Through-flow openings

30 Arrow

32 Air supply device

34 Air passage

36 Arrow

38 Member

40 Introduction element

42 Channels

44 Outlet

46 Straight line

48 Arrow head

50 Arrow

52 Closure element

54 Groove

56 Outer circumferential side coating surface

58 Lever

60 Closure portion

62 Pipeline element

64 End face

66 Inner circumferential side coating surface

E introduction point

Region B

TB1 first subregion

TB2 second subregion

Plane of symmetry of EB1

EB2 symmetry plane

F release position

S closed position

Claims

1. A burner (18) for an exhaust system (10) of an internal combustion engine, comprising:

a combustion chamber (22) formed by a chamber element (20) of the burner (18), in which a mixture of air as a first fluid and fuel as a second fluid is to be ignited and thus burns, whereby components of the exhaust system (10), in particular exhaust gas aftertreatment elements and/or exhaust gases of the internal combustion engine flowing through the exhaust system (10), can be heated; a channel (42) through which at least one of the fluids can flow and which opens into the combustion chamber (22), and through which at least one fluid can be introduced into the combustion chamber (22); and

a closure element (52) movable relative to the chamber element (20) between a closed position (S) fluidically isolating the passage (42) from the combustion chamber (22) and at least one released position (F) fluidically connecting the passage (42) to the combustion chamber (22),

It is characterized in that

The chamber element (20) has a recess (54) in which the closure element (52) is at least partially accommodated in the release position (F).

2. The burner (18) according to claim 1,

It is characterized in that

In the release position (F), at least one first sub-region (TB1) of the covering surface (56) on the outer circumferential side of the closing element (52) and at least one second sub-region (TB2) of the covering surface (24) on the inner circumferential side of the chamber element (20) form a rotationally symmetrical region (B) of the combustion chamber (22), the at least one first sub-region facing the combustion chamber (22) in the release position (F), and the at least one second sub-region opposite to the first sub-region (TB1) in the release position (F) and facing the combustion chamber (22) and the first sub-region (TB1) in the release position (F).

3. The burner (18) according to claim 1 or 2,

It is characterized in that

In the release position (F), at least one first sub-region (TB1) of the cladding surface (56) on the outer circumferential side of the closure element (52) facing the combustion chamber (22) in the release position (F) and at least one second sub-region (TB2) of the cladding surface (24) on the inner circumferential side of the chamber element (20) opposite to the first sub-region (TB1) in the release position (F) and facing the combustion chamber (22) and the first sub-region (TB1) in the release position (F) form a mirror-symmetrical region (B) relative to at least one symmetry plane (EB1) of the combustion chamber (22), wherein a straight line (46) extends in the symmetry plane (EB1), the straight line extending through the outlet opening (44) of the channel (42), the channel leading to the combustion chamber (22) via the outlet opening (44) of the channel, in particular through the center of the outlet opening (44).

4. Burner (18) according to any one of the preceding claims,

It is characterized in that

In the release position (F), the closure element (52) is at least predominantly or completely arranged in the recess (54).

5. Burner (18) according to any one of the preceding claims,

It is characterized in that

The closure element (52) has:

A lever (58) capable of pivoting relative to the chamber element (20) about a pivot axis (SA) between the release position (F) and the closed position (S), and a closure portion (60) constructed separately from the lever (58) and retained on the lever (58), the closure portion and the lever (58) being capable of pivoting together relative to the chamber element (20) about the pivot axis (SA) between the release position (F) and the closed position (S), the closure portion covering and thereby fluidically blocking the outlet opening (44) of the channel (42) through which the channel leads to the combustion chamber (22), and releasing the outlet opening (44) in the release position (F).

6. The burner (18) according to claim 5,

It is characterized in that

The pivot axis (SA) extends through the groove (54).

7. Burner (18) according to claim 5 or 6,

It is characterized in that

The closing portion (60) is held on the lever (58) with play so as to be movable in a limited manner relative to the lever (58).

8. Burner (18) according to any one of the preceding claims,

It is characterized in that

The inner contour of the recess (54) facing the closure element (52) in the release position (F) matches the outer contour of the closure element (52) facing the inner contour in the release position (F).

9. Burner (18) according to any one of the preceding claims,

It is characterized in that

At least one wall region (W) of the chamber element (20) adjoining the recess (52) is flush with the closure element (52) in the release position (F).

10. An internal combustion engine comprising at least one burner according to any one of the preceding claims.