Static mixer and exhaust gas treatment device

Abstract

The invention relates to a static mixer for an exhaust system of an internal combustion engine. The mixer has a wall structure that is arranged across the directional of flow in a pipe and has several layers of a corrugated sheeting material laying across one another in the direction of flow. The cells through which the flow can pass in the direction of flow are provided between the sheeting material of neighboring layers. The sheeting material has baffles for all or several of the cells. The baffles are arranged on the sheeting material so that they are arranged on their outgoing flow side in the case of said cells and extend in the direction of flow and across it.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred exemplary embodiments of the invention are depicted in the drawings and explained in greater detail in the following description, where the same reference numerals are used to refer to the same or similar or functionally identical components.

FIG. 1 a is a simplified basic sectional view of an exhaust treatment device;

FIG. 1 b is a simplified basic sectional view of an exhaust system;

FIG. 2 is a cross section through the exhaust gas treatment device and/or the exhaust system according to sectional lines II in FIGS. 1a and/or 1b;

FIG. 3 is an enlarged prospective detailed view of an oncoming flow side of a mixer;

FIG. 4 is an enlarged detailed view in the direction of flow of the oncoming flow side of the mixer;

FIG. 5 is an enlarged perspective detailed view of the outgoing flow side of the mixer;

FIG. 6 is an enlarged view of a detail of the mixer across the direction of flow;

FIG. 7 is a cross-sectional view of another embodiment,

FIG. 8 is a perspective view of the embodiment according to FIG. 7; and

FIG. 9 is a longitudinal section of the mixer from FIG. 8.

Claims

1. A static mixer for an exhaust system of an internal combustion engine, comprising: a wall structure arranged across the direction flow in a pipe;a plurality of layers of a corrugated sheeting material situated one above the other in said wall structure;wherein said plurality of layers form a plurality of cells through which the flow can pass in the direction of flow; andat least one baffle for at least one of said plurality of the cells, said baffle being arranged on at least a first of said plurality of layers of sheeting material in such a way that it is arranged on the outgoing flow side of said cells and extends across the direction of flow.

2. The mixer according to claim 1, wherein said sheeting material is uniform in all layers and has corrugations of the same wavelength and the same amplitude.

3. The mixer according to claim 1, wherein a first and a second of said layers of corrugated sheeting material are so arranged that said first layer is offset by one half wavelength from said second layer.

4. The mixer according to claim 1, wherein said corrugated sheeting material has a sinusoidal or rectangular or trapezoidal shape.

5. The mixer according to claim 1, wherein said sheeting material extends without interruption over at least first and second of said layers and said first layer is bent or folded over into said second layer on the lateral end.

6. The mixer according to claims 1, further comprising a plurality of baffles wherein said baffles are arranged regularly along the sheeting material.

7. The mixer according to claim 6, wherein a first baffle along the sheeting material protrude away from the sheeting material in an orientation opposite to the orientation of a second baffle with regard to the direction of flow.

8. The mixer according to claim 6, wherein a first baffle protrudes from said layer of sheeting material with the same orientation as the orientation of a second baffle with regard to the direction of flow, said first and second baffles being at a distance of two wavelengths apart from one another along the sheeting material.

9. The mixer according to claim 7, wherein said plurality of baffles comprises of a plurality of pairs of baffles, each pair of baffle comprising a first and a second baffle, wherein within each of said pair of baffles, said first and second baffles are arranged at a distance of one half-wavelength and wherein said first baffle of a first of said pair of baffles is arranged at a distance of three half-wavelengths from said first baffle of a second of said pair of baffles.

10. The mixer according to claim 6, wherein said first and second baffles in first and second of said plurality of cells protrude away from the sheeting material with opposite orientations with respect to the direction of flow.

11. The mixer according to claim 6, wherein said first and second baffles in first and second of said plurality of cells protrude away from the sheeting material with the same orientation with respect to the direction of flow.

12. The mixer according to claim 1, wherein said at least one baffle protruding away from the sheeting material with an opposite orientation with regard to the direction of flow is arranged directly adjacent to and along said sheeting material in the respective layer.

13. The mixer according to claim 1, wherein said first of said plurality of layers with baffles and at least a first of said plurality of layers without baffles are alternately opposite one another within said wall structure.

14. The mixer according to claim 6, wherein said baffles are angled by approximately 45 degrees with respect to the direction of flow.

15. The mixer according to claim 6, wherein said baffles are integrally molded on said sheeting material.

16. The mixer according to claim 1, wherein said baffle is of such dimension and is oriented with respect to the direction of flow so that it overlaps and seals one of said plurality of cells by at least 80% to 95% in the direction of flow.

17. The mixer according to claim 1, wherein a diameter of one of said plurality of said cells measured across the direction of flow is larger than its length measured in the direction of flow.

18. The mixer according to claim 1, wherein said baffle has a breakaway edge on its respective outgoing flow end.

19. The mixer according to claim 1, wherein a longitudinal extent of said baffle measured in the direction of flow is approximately equal to the length of one of said plurality of cells measured in the direction of flow.

20. The mixer according to claim 1, wherein a transverse extent of said baffle measured across the direction of flow is approximately equal to a diameter of one of said plurality of cells measured across the direction of flow.

21. The mixer according to claim 1, wherein baffle has a convex or concave curvature, especially a saddle-shaped curvature, of the oncoming flow side.

22. The mixer according to claim 1, wherein in the circumferential direction, said sheeting material is encompassed by a ring that is inserted into the pipe in the installed state of the mixer.

23. The mixer according to claim 1, wherein said sheeting material together with said ring forms a unit that can be preassembled and is arranged in the pipe in the installed state.

24. The mixer according to claim 1, wherein said sheeting material is attached to the pipe or said ring on lateral ends of at least one of said layers.

25. The mixer according to claim 1, wherein said sheeting material is arranged in loose contact between lateral ends of first and second of said plurality of layers.

26. An exhaust gas treatment device for an exhaust system of an internal combustion engine, comprising at least one exhaust gas treatment insert that is arranged in a tubular body of the exhaust gas treatment device;a mixer according to claim 1 arranged in said tubular body upstream from said exhaust gas treatment insert, said tubular body of the exhaust gas treatment device forming a pipe; andan injection device for introducing a liquid upstream from the mixer.

27. An exhaust system for a internal combustion engine, comprising at least one exhaust gas treatment device that is connected to an exhaust line of the exhaust system, said exhaust gas treatment device comprising at least one exhaust gas treatment insert arranged in a tubular body of said exhaust gas treatment device;a mixer according to claim 1 arranged upstream from said exhaust gas treatment device in the exhaust line, a pipe thereof being formed by the exhaust line of the exhaust system; andan injection device for introducing a liquid upstream from the mixer.