Burner for an exhaust-gas aftertreatment system, exhaust-gas aftertreatment system for an internal combustion engine
A burner for an exhaust-gas aftertreatment system. The burner includes a housing forming a combustion chamber. The housing has an outlet which is or can be connected to an exhaust-gas line of the exhaust-gas aftertreatment system. The burner further includes a fuel feed device for feeding fuel into the combustion chamber; a fresh-air feed device for feeding fresh air into the combustion chamber; and an ignition element for igniting a fresh-air/fuel mixture located in the combustion chamber. It is provided that the housing is designed such that the combustion chamber has a cylindrical main portion and a bulge protruding radially outward from the main portion, and that the ignition element is arranged in the bulge.
1 . A burner for an exhaust-gas aftertreatment system, comprising:
a housing forming a combustion chamber, the housing having an outlet which is or can be connected to an exhaust-gas line of the exhaust-gas aftertreatment system;
a fuel feeder configured to feed fuel into the combustion chamber;
a fresh-air feeder configured to feed fresh air into the combustion chamber; and
an ignition configured to ignite a fresh-air/fuel mixture located in the combustion chamber;
wherein the housing is configured such that the combustion chamber has a cylindrical main portion and a bulge protruding radially outward from the main portion, and the ignition is arranged in the bulge,
wherein the combustion chamber is configured such that a fresh-air/fuel mixture introduced into the cylindrical main portion flows in a swirl flow, and the bulge is configured to generate a recirculation flow that rotates in the opposite direction relative to the swirl flow.
2 . The burner according to claim 1 , wherein the housing has a first housing part forming the main portion and a second housing part forming the bulge, wherein the first and the second housing part are manufactured separately from each other, and wherein the second housing part is arranged in an aperture in a casing wall of the first housing part.
3 . The burner according to claim 2 , wherein the first housing part has a circular cross-section.
4 . The burner according to claim 2 , wherein the second housing part has a cross-section with a C-shaped profile.
5 . The burner according to claim 2 , wherein the fresh-air feeder has a sleeve-shaped fresh-air feed chamber, wherein the fresh-air feed chamber radially encloses the first housing part, and wherein the second housing part projects radially through the fresh-air feed chamber.
6 . The burner according to claim 1 , wherein the bulge extends in a circumferential direction of the main portion over a circumferential angle of 10° to 50°.
7 . The burner according to claim 1 , wherein an axial extension of the bulge is smaller than an axial extension of the main portion.
8 . The burner according to claim 1 , wherein a ratio of a volume of the main portion to the volume of the bulge is 200:1 to 50:1.
9 . The burner according to claim 1 , wherein a yaw angle of the ignition is in an angular range that begins with 0° and ends with 45°, wherein the yaw angle describes a rotation of a longitudinal center axis of the ignition relative to a longitudinal center axis of the main portion about a vertical axis, which is aligned perpendicularly to the longitudinal center axis of the main portion and runs through the longitudinal center axis of the main portion and through the ignition.
10 . The burner according to claim 1 , wherein a pitch angle of the ignition is in an angular range that begins with 0° and ends with 70°, wherein the pitch angle describes a rotation of a longitudinal center axis of the ignition relative to a longitudinal center axis of the main portion about a transverse axis which is aligned perpendicularly to the longitudinal center axis of the main portion and the vertical axis and runs through the ignition.
11 . The burner according to claim 1 , wherein the ignition element is arranged such that a longitudinal center axis of the ignition is aligned in parallel with a longitudinal center axis of the main portion.
12 . The burner according to claim 1 , wherein the housing has a rounding at at least one transition from the main portion to the bulge.
13 . The burner according to claim 1 , wherein the ignition is a ceramic glow plug.
14 . The burner according to claim 1 , wherein the fuel feeder and the fresh-air feeder together form a two-fluid nozzle.
15 . An exhaust-gas aftertreatment system for an internal combustion engine, comprising:
a burner, including:
a housing forming a combustion chamber, the housing having an outlet which is or can be connected to an exhaust-gas line of the exhaust-gas aftertreatment system,
a fuel feed device configured to feed fuel into the combustion chamber,
a fresh-air feed device configured to feed fresh air into the combustion chamber, and
an ignition element configured to ignite a fresh-air/fuel mixture located in the combustion chamber,
wherein the housing is configured such that the combustion chamber has a cylindrical main portion and a bulge protruding radially outward from the main portion, and the ignition element is arranged in the bulge,
wherein the combustion chamber is configured such that a fresh-air/fuel mixture introduced into the cylindrical main portion flows in a swirl flow, and the bulge is configured to generate a recirculation flow that rotates in the opposite direction relative to the swirl flow.