Exhaust gas burner device for an exhaust aftertreatment system, vehicle and process

Abstract

The invention relates to an exhaust gas burner device (10) for an exhaust aftertreatment system (2) of a vehicle (1), comprising a combustion chamber (11) in which a combustion flame can be generated from a mixture, a nozzle unit (12) for injecting a fuel (201), and an air guide (20) for supplying intake air (200) to the combustion chamber (11) with an inner guide section (22) which at least partially surrounds the combustion chamber (11), an outer guide section (23) upstream of the inner guide section (22) which at least partially surrounds the inner guide section (22), and an inlet section (21) for supplying the intake air (200) to the outer guide section (23). The invention further relates to a vehicle (1) and a method.

Description

[0001] The invention relates to an exhaust gas burner device for an exhaust gas aftertreatment system, a vehicle, and a method for operating an exhaust gas aftertreatment system.

[0002] It is known from the prior art to provide exhaust aftertreatment systems that use an exhaust burner to reduce pollutants by heating the exhaust gas. This typically involves igniting a mixture of air and fuel in a combustion chamber. The fuel is injected into the combustion chamber via an injection nozzle, which is often water-cooled. However, the water cooling system forms an additional component with a separate circuit. Furthermore, ensuring the water cooling system's tightness can be complex.

[0003] From document DE 11 2014 001 010 T5, it is known to provide an air duct formed by several shells. In this case, air in the exhaust aftertreatment system is divided into two streams. One of the streams is directed directly into the combustion chamber via the air duct, while the other stream directs a smaller amount of air into the nozzle. Dividing the air duct requires a corresponding duct network, which takes up installation space and requires additional ducts. Furthermore, nozzle cooling can be optimized.

[0004] It is an object of the present invention to at least partially remedy the above-mentioned disadvantages known from the prior art. In particular, it is an object of the present invention to improve the temperature control of at least one component of an exhaust gas burner device and, at the same time, to enable a compact design of the exhaust gas burner device.

[0005] The above object is achieved by an exhaust gas burner device having the features of claim 1, a vehicle having the features of claim 11, and a method having the features of claim 13. Further features and details of the invention emerge from the respective subclaims, the description, and the drawings. Features and details described in connection with the exhaust gas burner device according to the invention naturally also apply in connection with the vehicle according to the invention and / or the method according to the invention, and vice versa, so that with regard to the disclosure of the individual aspects of the invention, reference is always made to each other.

[0006] According to a first aspect of the invention, an exhaust gas burner device is provided for an exhaust gas aftertreatment system of a vehicle. The exhaust gas burner device has a combustion chamber in which a combustion flame can be generated from a mixture. The exhaust gas burner device further comprises a nozzle unit for injecting a fuel. The exhaust gas burner device also has an air duct for supplying supply air to the combustion chamber. The air duct comprises an inner guide section which at least partially encloses the combustion chamber. The air duct also comprises an outer guide section which is arranged upstream of the inner guide section, in particular hydraulically, and which at least partially encloses the inner guide section. The air duct also has an inlet section for supplying the supply air to the outer guide section.The nozzle unit has a cooling surface that runs along the inlet section to enable the nozzle unit to be tempered by the supply air in the inlet section.

[0007] The vehicle is, in particular, a motor vehicle with an internal combustion engine. The exhaust gas aftertreatment system can comprise a pump, through which the supply air can be conveyed via a line system to the exhaust gas burner device, in particular to the inlet section of the exhaust gas burner device. The fuel can advantageously be a fuel, preferably a diesel fuel.

[0008] The combustion chamber can be formed by a housing of the exhaust gas burner device, in which a combustion process can be carried out by the combustion flame. The mixture can comprise at least the fuel and the supply air. The mixture can thus be understood, in particular, as a fuel-air mixture. The combustion flame can be generated by igniting the mixture. For this purpose, the exhaust gas burner device preferably has at least one ignition source.

[0009] The nozzle unit can have at least one injection nozzle for injecting the fuel into the combustion chamber. The fuel can spread conically in the combustion chamber and form a mixture with the intake air. The fuel is preferably a vehicle fuel.

[0010] The air guide can be formed by a housing of the exhaust gas burner device. For example, the housing can comprise several shells and / or walls, which form the inlet section and the inner and outer guide sections.

[0011] The inlet section, the inner guide section and / or the outer guide section can be designed like a line. Preferably, the inner and outer guide sections are each formed by a volume that runs at least partially or completely around the combustion chamber and / or a jacket that runs at least partially or completely around the combustion chamber. The supply air can be guided from the inlet section to the combustion chamber through the inner and outer guide sections. The upstream arrangement of the outer guide section particularly ensures that the supply air first passes through the outer guide section and then the inner guide section when flowing from the inlet section into the combustion chamber. The outer guide section is therefore preferably hydraulically arranged upstream of the inner guide section with respect to a flow direction of the supply air as it flows into the combustion chamber.The inner guide section is arranged in particular downstream of the outer guide section.

[0012] The combustion chamber can, in particular, be cylindrical. The first and second guide sections can be cylindrical in shape, at least in part or entirely. This allows the air guide to form a double envelope around the combustion chamber in order to improve the temperature control of the combustion chamber. In particular, the outer guide section can provide thermal insulation from the surroundings. The inner guide section can preheat the supply air before it enters the combustion chamber, thereby accelerating the heating of the combustion chamber, particularly at the start of a combustion process. The inlet section can comprise an opening for an air inlet, which can be connected to a piping system of the exhaust gas aftertreatment system.

[0013] Preferably, a housing of the exhaust gas burner device, in particular a housing part of the combustion chamber and / or the air duct, comprises an aluminum material and / or a plastic, in particular in the form of a high-temperature plastic. The housing part can, for example, form a casing part of the outer guide section and / or comprise a wall of the air duct. This can reduce material costs and / or the weight of the exhaust gas burner device.

[0014] The temperature control of the nozzle unit can, in particular, comprise cooling of the nozzle unit. The cooling surface of the nozzle unit can, in particular, form a heat exchanger. Because the cooling surface runs along the inlet section, the heat exchanger effect can cool the nozzle unit when the supply air flows past and / or along the cooling surface. Preferably, the cooling surface can form a wall of the inlet section. Thus, the cooling surface can be directly contacted by the supply air to improve heat conduction.

[0015] It has therefore been recognized within the scope of the present invention that the supply air which is fed to the combustion chamber can advantageously be used to control the temperature of the nozzle unit, i.e. in particular to cool it. For this purpose, it has also been recognized that the inlet section allows a high volume flow of the supply air, whereby the cooling capacity can be increased if this volume flow interacts with the nozzle unit. The cooling surface makes it possible to maintain a functional separation between the nozzle unit and the inlet section in a simple manner, while at the same time improving heat exchange. The resulting multifunctional integration of the inlet section also allows the exhaust gas burner device to be designed to be compact, whereby the use of installation space can be improved.

[0016] Within the scope of the invention, it is further conceivable for the cooling surface to have ribbing that projects into the inlet section. Thus, the cooling surface can be arranged directly in the inlet section and / or define part of the inlet section. The ribbing can enlarge the cooling surface. Furthermore, the ribbing can comprise guide surfaces that the supply air can flow against in the inlet section. As a result, a flow of the supply air through the cooling surface can be influenced. For example, it can be provided that the ribbing is designed in a helical manner in order to influence, in particular to generate or reduce, a swirl in the flow.

[0017] Furthermore, in an exhaust gas burner device according to the invention, it can advantageously be provided that the inlet section has a bypass opening for a fluid communication connection with the combustion chamber, in particular wherein the bypass opening is connected parallel to the outer guide section, so that a portion of the supply air can be guided directly into the combustion chamber via the bypass opening, in particular bypassing the inner and outer guide sections. It can be provided that the bypass opening is designed to be closable. Preferably, the bypass opening is arranged coaxially and / or circumferentially around a nozzle opening of the nozzle unit to the combustion chamber. For example, the bypass opening can be designed in a ring around the nozzle unit. This can further improve the temperature control, in particular the cooling, of the nozzle unit. The ring-like design of the bypass openings can include interruptions for connections to a nozzle body.In this case, an unjointed, i.e., in particular, a flush, design may be sufficient. Furthermore, it is conceivable for the bypass opening to be non-circular, i.e., in particular, with a varying distance from the nozzle unit. Furthermore, it is conceivable for multiple bypass openings to be provided, which are arranged, in particular, in a ring-like manner around the nozzle unit. The at least one bypass opening can have a smaller cross-sectional area than the inner and / or outer guide section.

[0018] Thus, a smaller portion of the supply air can flow into the combustion chamber through the bypass opening than through the inner and outer guide sections. The bypass opening can thus reduce pressure losses. This can, in particular, relieve the load on a pump in the exhaust gas aftertreatment system. The ratio of the mass flow through the bypass opening to the total mass flow can preferably be between 1 / 3 and 1 / 30.

[0019] It is further conceivable in an exhaust gas burner device according to the invention for the nozzle unit to have a longitudinal axis along which the fuel can be introduced into the combustion chamber, in particular wherein the inlet section is formed coaxially to the longitudinal axis. The longitudinal axis can in particular be a geometric axis. The longitudinal axis can, for example, be arranged centrally to an ejection cone when the fuel is ejected from the nozzle unit into the combustion chamber. In particular, the longitudinal axis of the nozzle unit can run coaxially to a cylinder axis of the combustion chamber and / or of the first and / or second guide section. The inlet section can, for example, be arranged circumferentially around the nozzle unit. In particular, the cooling surface can be formed circumferentially on an outer circumference of the nozzle unit. Thus, the nozzle unit can in particular be fully temperature-controlled by the supply air flowing through the inlet section.Furthermore, this can achieve a uniform distribution of the supply air during the flow into the outer guide section and / or to the bypass opening.

[0020] In an exhaust gas burner device according to the invention, it can preferably be provided that the inlet section and / or the inner guide section has a flow medium for influencing a swirl of the supply air. Preferably, the inlet section and the inner guide section each have a flow medium for influencing a swirl of the supply air. The flow medium of the inlet section can, for example, be spiral-shaped. The spiral-shaped flow medium can be understood to mean a means for influencing the air flow of the supply air in the inlet section. For example, the flow medium can have an inlet spiral and / or guide means arranged within the inlet section to deflect the flow. However, it is also conceivable for the flow medium to define a spiral-shaped path for the supply air. In this case, the swirl can be reduced or a swirl-free flow can be generated.The spiral-shaped flow medium can be formed by the ribbing of the cooling surface or in addition to the ribbing of the cooling surface. The flow medium can thus achieve a swirl-free or low-swirl inflow of the supply air in the inlet section, thereby improving pressure distribution in the exhaust gas burner device. The flow medium of the inner guide section can, for example, comprise guide vanes for generating swirl.

[0021] In particular, the guide vanes can be angled to the flow direction of the supply air in the inner guide section. This can improve the flow of the supply air as it flows into the combustion chamber.

[0022] Furthermore, in an exhaust gas burner device according to the invention, it is conceivable that the air duct has a penetration region in which an ignition source is arranged, in particular wherein the ignition source projects through the inner and outer guide sections into the combustion chamber, preferably perpendicular to a flow direction of the supply air in the inner and / or outer guide sections, so that the ignition source is tempered by the supply air in the inner and outer guide sections. The ignition source can be, for example, a spark plug or a thermal igniter. In particular, the ignition source serves to ignite a combustion flame of the mixture in the combustion chamber. The inner and outer guide sections can be interrupted in the penetration region. For example, the penetration region can comprise an opening in the air duct, which opening is sealed in particular with respect to the ignition source and extends through the inner and outer guide sections.The seal can therefore in particular have a sealing effect with respect to an outer and / or inner casing of the inner and / or outer guide section and / or the wall of the air guide. This can in particular also achieve a sealing effect with respect to the environment of the exhaust gas burner device. In particular, thermal insulation with respect to the inner guide section, which is particularly heated during operation, and / or thermal coupling to the outer guide section, which is particularly cool during operation, can be provided at the penetration region. The penetration region can run radially to the combustion chamber, i.e., in particular perpendicular to the longitudinal axis of the nozzle unit. By arranging the ignition source in the penetration region, the ignition source can therefore also be tempered by the supply air, here in particular in the inner and outer guide sections. The heat can, for example, be dissipated to the outside.

[0023] Preferably, in an exhaust gas burner device according to the invention, the ignition source can have an inner ignition source section that projects through the inner and outer guide sections into the combustion chamber, and an outer ignition source section that projects beyond the outer guide section, wherein a temperature control means for dissipating heat is arranged on the outer ignition source section. The inner and outer ignition source sections can be cylindrical. The temperature control means can, for example, be designed as a ribbed attachment. For example, the temperature control means can have cross-shaped ribs that run axially and / or radially to the ignition source. With radially extending ribs, a particularly high degree of efficiency of the ribs can be achieved. Furthermore, it can be provided that the ribs run circumferentially around a circumference of the temperature control means, so that the temperature control means can advantageously be designed as a turned part.Furthermore, the temperature control medium can be plugged and / or screwed onto the ignition source. The temperature control medium can thus advantageously dissipate heat into the environment, thereby improving temperature control and, in particular, reducing cooling by the supply air to the ignition source.

[0024] Preferably, in an exhaust gas burner device according to the invention, it can be provided that a damming means for dividing the combustion chamber into a primary chamber region for generating a combustion flame and a secondary chamber region for discharging the mixture after combustion is provided in the combustion chamber, in particular wherein a return means is provided in the inner guide section of the air guide, which return means has a return opening in order to suck a part of the mixture from the primary chamber region into the inner guide section. It can be provided that the return opening is designed to be closable. A fluid communication connection between the primary chamber region and the inner guide section can be created through the return opening. The damming means can in particular comprise a baffle plate and / or a baffle plate. The damming means can prevent movement of the combustion flame within the combustion chamber, ie, in particular a migration of the combustion flame from the primary chamber region leading to flame termination, can be prevented. The damming means can be attached to a wall of the combustion chamber, in particular perpendicular to a cylinder axis of the combustion chamber. The return means can prevent a build-up of back pressure in the region of the damming means, which influences the flow conditions within the combustion chamber, in particular causing turbulence. Thus, the pressure conditions, in particular in the primary chamber region, can be improved by the return means. Preferably, the return means can have a plurality of return openings, in particular arranged circumferentially around the combustion chamber. The increased temperature can improve evaporation of the fuel in the combustion chamber. In particular, the exhaust gas burner device can thereby function as a blue burner, whereby less heat radiation and / or less soot is produced.This can further improve exhaust gas aftertreatment overall. Preferably, the ratio of a mass flow through the recirculation opening to a mass flow through the inlet section, ie, in particular, a total air flow, can be between 1 / 3 and 1 / 20.

[0025] Preferably, in an exhaust gas burner device according to the invention, the recirculation means can comprise at least one constriction of the inner guide section, through which a nozzle is formed to draw the mixture from the primary chamber region into the inner guide section. The constriction can comprise a cross-sectional reduction of a flow cross-section in the inner guide section. In particular, air and / or exhaust gas in the region of the damming means can be discharged more quickly due to the constriction of the inner guide section. Thus, the pressure conditions can be improved by a simple measure.

[0026] Furthermore, in an exhaust gas burner device according to the invention, it is conceivable that the inner and outer guide sections are separated from one another by a wall, wherein the wall has a bulge through which the constriction is formed. In the region of the bulge, the outer guide section can have a locally enlarged flow cross-section, and the inner guide section a locally reduced flow cross-section. This eliminates the need to provide an additional component for the constriction. In particular, the bulge can be introduced into the wall by a molding process. For example, the wall can comprise a sheet metal or a plastic component in which the bulge is configured by a deformation and / or a curved profile. This allows the exhaust gas burner device to be compact and cost-effective to manufacture.

[0027] According to a further aspect of the invention, a vehicle is provided. The vehicle has an exhaust gas aftertreatment system with an exhaust gas burner device according to the invention.

[0028] Thus, a vehicle according to the invention brings with it the same advantages as have already been described in detail with reference to an exhaust gas burner device according to the invention.

[0029] Furthermore, in a vehicle according to the invention, it is conceivable for the exhaust gas aftertreatment system to have a pump unit for conveying supply air to the exhaust gas burner device and a control unit for controlling the pump unit, wherein the control unit is designed to generate a follow-up of the pump unit for continued temperature control of a nozzle unit of the exhaust gas burner device after completion of a combustion process. The control unit can comprise a processor and / or a microprocessor. Furthermore, the control unit can be at least partially or completely integrated into a central control unit of the vehicle. However, it is also conceivable for the control unit to be at least partially or completely integrated into one or more decentralized control units. Due to the follow-up, the flow of supply air at the cooling surface of the nozzle unit can be continued, even if supply air is no longer required for the combustion process in the combustion chamber.Thus, the after-run function can prevent the nozzle unit from being damaged by persistent temperatures, particularly in the form of heat buildup, after the combustion process. Provision can be made for the nozzle unit, the ignition source, and / or the combustion chamber to have a sensor, particularly in the form of a temperature sensor, connected to the control unit. This allows the after-run function to be generated depending on the sensor's measurement data, particularly until the nozzle unit, the ignition source, and / or the combustion chamber falls below a predefined temperature limit.

[0030] According to a further aspect of the invention, a method for operating an exhaust gas aftertreatment system is provided. The exhaust gas aftertreatment system has an exhaust gas burner device according to the invention. The method comprises, in particular in the form of method steps: - supplying supply air into an air duct of the exhaust gas burner device, in particular by a pump unit of the exhaust gas aftertreatment system, - Tempering a nozzle unit of the exhaust gas burner device by guiding the supply air along a cooling surface of the nozzle unit, in particular by a convection process, - introducing at least part of the supply air into a combustion chamber of the exhaust gas burner device via an outer guide section and an inner guide section, wherein the inner guide section at least partially encloses the combustion chamber, and the outer guide section, which is arranged upstream of the inner guide section, at least partially encloses the inner guide section.

[0031] Thus, a method according to the invention provides the same advantages as those already described in detail with reference to an exhaust gas burner device according to the invention and / or a vehicle according to the invention. Preferably, the exhaust gas aftertreatment system is part of a vehicle according to the invention. Provision can be made for the entire supply air to be guided into the combustion chamber via the inner and outer guide sections. However, it is also conceivable for only a portion of the supply air to be guided into the combustion chamber via the inner and outer guide sections and another portion via a bypass opening.

[0032] In particular, it is conceivable in a method according to the invention that a shutdown process is carried out in which a supply of fuel is terminated before the supply of supply air is terminated as a function of at least one limit temperature. It can be provided that the limit temperature is compared with a temperature measured in the combustion chamber by a temperature sensor and / or with a temperature calculated using a computer model. In particular, it can thus be provided that after the conclusion of a combustion process in the combustion chamber, a pump unit is controlled to generate a follow-up for continued temperature control of the nozzle unit. The introduction of supply air can be continued until the follow-up is terminated.

[0033] Further advantages, features, and details of the invention will become apparent from the following description, which, with reference to the drawings, describes embodiments of the invention in detail. The features mentioned in the claims and in the description may be essential to the invention individually or in any combination. They show schematically: Fig. 1 a vehicle according to the invention with an exhaust aftertreatment system, Fig. 2 an exhaust gas burner device of the exhaust gas aftertreatment system in a schematic cross section, and Fig. 3 + Fig. 4 Tempering agents of an ignition source in different designs.

[0034] In the following description of some embodiments of the invention, the same reference numerals are used for the same technical features even in different embodiments.

[0035] Fig. 1 shows a vehicle 1 according to the invention with an exhaust gas aftertreatment system 2. The vehicle 1 comprises an internal combustion engine whose exhaust gases can be aftertreated by the exhaust gas aftertreatment system 2 in order to reduce pollutants in the exhaust gas. For heating the exhaust gases in a mixing device 5, the exhaust gas aftertreatment system 2 has an exhaust gas burner device 10, by which a heated and / or combusted mixture can be generated, which is combined with the exhaust gas of the internal combustion engine of the vehicle 1 in the mixing device 5. The exhaust gas aftertreatment system 2 further comprises a pump unit 3 for conveying supply air 200 to the exhaust gas burner device 10 and a control unit 4 for controlling the pump unit 3.

[0036] As in Fig. 2, the exhaust gas burner device 10 comprises a combustion chamber 11 in which a combustion flame can be generated from the mixture comprising the supply air 200 and a fuel 201. The fuel 201 can, in particular, be a fuel of the vehicle 1. The combustion chamber 11 is formed by a cylindrical housing 16. Furthermore, a longitudinal axis 12.1 of a nozzle unit 12 of the exhaust gas burner device 10, which is designed to inject the fuel 201 into the combustion chamber 11, runs coaxially to a cylinder axis of the combustion chamber 11. The fuel 201 can be introduced into the combustion chamber 11 through the nozzle unit 12, in particular along the longitudinal axis 12.1. For example, the fuel 201 can be distributed conically around the longitudinal axis 12.1 in the combustion chamber 11. To ignite the mixture and to generate a combustion flame in the combustion chamber 11, the exhaust gas burner device 10 further comprises an ignition source 14.

[0037] The exhaust gas burner device 10 further comprises an air guide 20 for supplying the supply air 200 to the combustion chamber 11. The air guide 20 has an inner guide section 22, which at least partially encloses the combustion chamber 11, and an outer guide section 23, which at least partially encloses the inner guide section 22 and is arranged upstream of the inner guide section 22, in particular hydraulically. The inner and outer guide sections 22, 23 are separated from one another by a wall 27. By placing the outer guide section 23 upstream, it is provided that the supply air 200 is first guided through the outer guide section 23 before the supply air 200 is guided through the inner guide section 22. In particular, the inner and outer guide sections 22, 23 form hollow cylinders that encircle the combustion chamber 11 and enclose the combustion chamber 11 like a jacket.As a result, the supply air 200 can be pre-tempered in the inner guide section 22 and form thermal insulation in the outer guide section 23. This can accelerate heating within the combustion chamber 11. In particular, better mixture formation conditions can be created in a stationary state. Furthermore, a damming means 15 is arranged in the combustion chamber 11 for dividing the combustion chamber 11 into a primary chamber region 11.1 for generating the combustion flame and a secondary chamber region 11.2 for discharging the mixture after combustion.

[0038] The air duct 20 has a penetration area 26 in which the ignition source 14 is arranged. The ignition source 14 protrudes through the inner and outer guide sections 22, 23 into the combustion chamber 11, so that the ignition source 14 is tempered by the supply air 200 in the inner and outer guide sections 22, 23. This eliminates the need for water cooling of the ignition source 14. In particular, a seal with a sealing effect against an outer and / or inner casing 28, 29 of the inner and / or outer guide sections 22, 23 and / or against the wall 27 of the air duct 20 can be provided at the penetration area 26. To further increase the cooling performance, the ignition source 14 comprises an inner ignition source section 14.1, which projects through the inner and outer guide sections 22, 23 into the combustion chamber 11, and an outer ignition source section 14.2, which protrudes particularly outwardly from the outer guide section 23. On the outer ignition source section 14.2, a temperature control device 14.3 is arranged for dissipating heat. Exemplary designs of the temperature control device 14.3 are shown in the . Fig. 3 and Fig. 4. The ignition source 14, in particular the ignition source section 14.2, can be screwed and / or welded into a central opening of the temperature control medium 14.3. The temperature control medium 14.3 has ribs that can accelerate the dissipation of heat.

[0039] To supply the supply air 200 to the outer guide section 23, the exhaust gas burner device 10 further comprises an inlet section 21, which is formed at least partially coaxially with the longitudinal axis 12.1 of the nozzle unit 12, such that the inlet section 21 surrounds the nozzle unit 12. It is conceivable for an injection valve of the nozzle unit 12 to be embedded in a casing, such that the injection valve only comes into contact with the supply air 200 and / or the exhaust gas at a tip of the outlet S. This can facilitate replacement in the event of damage. The inlet section 21 further comprises a bypass opening 24 for a fluid communication connection with the combustion chamber 11.The bypass opening 24 is connected parallel to the outer guide section 23, so that a portion of the supply air 200 can be guided directly into the combustion chamber 11 via the bypass opening 24, bypassing the inner and outer guide sections 22, 23, in particular to reduce pressure losses. This improves the pressure conditions in the exhaust gas burner device 10 and relieves the load on the pump unit 3. Furthermore, the inlet section 21 and the inner guide section 22 have a flow medium 25 for influencing a swirl of the supply air 200, in particular to improve the flow and / or the pressure conditions in the air guide 20 and in the combustion chamber 11.

[0040] For temperature control of the nozzle unit 12, it is further provided that the nozzle unit 12 has a cooling surface 13 that runs along the inlet section 21 to enable temperature control, i.e., in particular cooling, of the nozzle unit 12 by the supply air 200 in the inlet section 21. The cooling surface 13 comprises ribbing 13.1 that projects into the inlet section 21 to improve the dissipation of heat from the nozzle unit 12 via the supply air 200. Preferably, the control unit 4 is designed to generate a follow-up flow of the pump unit 3 for continued temperature control of a nozzle unit 12 of the exhaust gas burner device 10 after completion of a combustion process. As a result, cooling can continue even after the combustion process has been completed.

[0041] In order to suck a portion of the mixture from the primary chamber region 11.1, particularly that accumulated at the damming means 15, into the inner guide section 22, a return means 30 comprising a return opening 31 is provided in the inner guide section 22 of the air guide 20. Furthermore, the return means 30 comprises at least one constriction 32 of the inner guide section 22, through which a nozzle is formed. To form the constriction 32, a bulge 33 is provided in the wall 27 between the inner and outer guide sections 22, 23.

[0042] Thus, in a method for operating the exhaust gas aftertreatment system 2, the supply air 200 is first fed into the air duct 20 of the exhaust gas burner device 10. By guiding the supply air 200 along the cooling surface 13 of the nozzle unit 12, the temperature of the nozzle unit 12 is further controlled. Subsequently, at least a portion of the supply air 200 is introduced into the combustion chamber 11 of the exhaust gas burner device 10 via the outer guide section 23 and then the inner guide section 22 of the air duct 20. Preferably, a shutdown process is also carried out in which a supply of fuel 201 is terminated before the supply of the supply air 200 is terminated depending on at least one limit temperature. It can be provided that the limit temperature for this purpose is compared with a temperature measured in the combustion chamber 11 by a temperature sensor 34 and / or with a temperature calculated using a computer model.

[0043] The above explanation of the embodiments describes the present invention exclusively by way of examples. Of course, individual features of the embodiments can be freely combined with one another, provided they are technically feasible, particularly within the scope of protection defined by the patent claims, without departing from the scope of the present invention. List of reference symbols 1 vehicle 2 exhaust aftertreatment system 3 Pump unit 4 Control unit 5 Mixing device 10 Exhaust gas burner device 11 Combustion chamber 11.1 primary chamber area 11.2 secondary chamber area 12 nozzle unit 12.1 Longitudinal axis 13 Cooling surface 13.1 Ribbing 14 Ignition source 14.1 internal ignition source section 14.2 external ignition source section 14.3 Tempering agents 15 dunnage 16 housings 20 Air duct 21 Entrance section 22 inner guide section 23 outer guide section 24 Bypass opening 25 Fluids 26 penetration area 27 wall 28 outer shell 29 inner coat 30 repatriation aids 31 Return opening 32 Constriction 33 bulge 34 Temperature sensor 200 supply air 201 Fuel S Exit QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This 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

[0000] DE 11 2014 001 010 T5

[0003]

Claims

[1] Exhaust gas burner device (10) for an exhaust gas aftertreatment system (2) of a vehicle (1) comprising a combustion chamber (11) in which a combustion flame can be generated from a mixture, a nozzle unit (12) for injecting a fuel (201), and an air guide (20) for supplying supply air (200) to the combustion chamber (11) with an inner guide section (22) which at least partially encloses the combustion chamber (11), an outer guide section (23) upstream of the inner guide section (22) which at least partially encloses the inner guide section (22), and an inlet section (21) for supplying the supply air (200) to the outer guide section (23), wherein the nozzle unit (12) has a cooling surface (13) which runs along the inlet section (21) in order to enable a temperature control of the nozzle unit (12) by the supply air (200) in the inlet section (21). [2] Exhaust gas burner device according to claim 1, characterized by that the cooling surface (13) has a ribbing (13.1) which projects into the inlet section (21). [3] Exhaust gas burner device (10) according to claim 1 or 2, characterized by in that the inlet section (21) has a bypass opening (24) for a fluid communication connection with the combustion chamber (11), wherein the bypass opening (24) is connected parallel to the outer guide section (23) so that a part of the supply air (200) can be guided directly into the combustion chamber (11) via the bypass opening (24), bypassing the inner and outer guide sections (22, 23). [4] Exhaust gas burner device (10) according to one of the preceding claims, characterized by that the nozzle unit (12) has a longitudinal axis (12.1) along which the fuel (201) can be introduced into the combustion chamber (11), wherein the inlet section (21) is formed coaxially to the longitudinal axis (12.1). [5] Exhaust gas burner device (10) according to one of the preceding claims, characterized by that the inlet section (21) and / or the inner guide section (22) has a flow means (25) for influencing a swirl of the supply air (200). [6] Exhaust gas burner device (10) according to one of the preceding claims, characterized by that the air guide (20) has a penetration region (26) in which an ignition source (14) is arranged, wherein the ignition source (14) projects through the inner and outer guide section (22, 23) into the combustion chamber (11), so that the ignition source (14) is tempered by the supply air (200) in the inner and outer guide section (22, 23). [7] Exhaust gas burner device (10) according to claim 6, characterized bythat the ignition source (14) has an inner ignition source section (14.1) which projects through the inner and outer guide sections (22, 23) into the combustion chamber (11), and an outer ignition source section (14.2) which projects relative to the outer guide section (23), wherein a temperature control means (14.3) for dissipating heat is arranged on the outer ignition source section (14.2). [8] Exhaust gas burner device (10) according to one of the preceding claims, characterized bythat in the combustion chamber (11) there is a damming means (15) for dividing the combustion chamber (11) into a primary chamber area (11.1) for generating a combustion flame and a secondary chamber area (11.2) for discharging the mixture after combustion, wherein in the inner guide section (22) of the air guide (20) there is provided a return means (30) which has a return opening (31) for sucking part of the mixture from the primary chamber area (11.1) into the inner guide section (22). [9] Exhaust gas burner device (10) according to claim 8, characterized by that the return means (30) comprises at least one constriction (32) of the inner guide section (22), through which a nozzle is formed in order to suck the mixture from the primary chamber region (11.1) into the inner guide section (22). [10] Exhaust gas burner device (10) according to claim 9, characterized bythat the inner and outer guide sections (22, 23) are separated from one another by a wall (27), wherein the wall (27) has a bulge (33) by which the constriction (32) is formed. [11] Vehicle (1) comprising an exhaust gas aftertreatment system (2) with an exhaust gas burner device (10) according to one of the preceding claims. [12] Vehicle (1) according to claim 11, characterized by that the exhaust gas aftertreatment system (2) has a pump unit (3) for conveying supply air (200) to the exhaust gas burner device (10) and a control unit (4) for controlling the pump unit (3), wherein the control unit (4) is designed to generate a run-on of the pump unit (3) for continued tempering of a nozzle unit (12) of the exhaust gas burner device (10) after completion of a combustion process. [13] Method for operating an exhaust gas aftertreatment system (2) with an exhaust gas burner device (10) according to one of claims 1 to 10, comprising: - supplying an air supply (200) into an air duct (20) of the exhaust gas burner device (10), - tempering a nozzle unit (12) of the exhaust gas burner device (10) by guiding the supply air (200) along a cooling surface (13) of the nozzle unit (12), - introducing at least part of the supply air (200) into a combustion chamber (11) of the exhaust gas burner device (10) via an outer guide section (23) and an inner guide section (22), wherein the inner guide section (22) at least partially encloses the combustion chamber (11), and the outer guide section (23), which is arranged upstream of the inner guide section (22), at least partially encloses the inner guide section (22). [14] Method according to claim 13, characterized bythat a shutdown process is carried out in which a supply of fuel (201) is terminated before the supply of supply air (200) is terminated as a function of at least one limit temperature.

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