Rotational flow mixer, tail gas postprocessor, engine and vehicle

Abstract

The utility model belongs to the technical field of tail gas after-treatment, and discloses a rotational flow mixer, a tail gas after-treatment device, an engine and a vehicle. The cyclone mixer comprises a cover body, a shell, a cyclone pipe, an inner pipe and an outer pipe, the inner pipe and the outer pipe are coaxially arranged, an annular channel is formed between the inner pipe and the outer pipe, a plurality of meshes are formed in the annular channel and the upper end of the inner pipe, and the meshes are evenly distributed in the circumferential direction of the inner pipe at intervals to form mesh sections. The annular channel is arranged between the inner pipe and the outer pipe, so that the heat preservation of the wall surface is facilitated, the mixing temperature of gas and urea is ensured, and the tail gas treatment effect is improved; the multi-mesh structure is arranged at the upper end of the inner pipe, so that gas in the inner pipe enters the annular channel through the multi-mesh structure, collision evaporation and heat exchange of urea particles can be improved, the outer pipe is in contact with airflow, the heat preservation performance is good, the urea crystallization risk can be further reduced, and the tail gas aftertreatment effect is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of exhaust gas post-processing, in particular to a cyclone mixer, an exhaust gas post-processor, an engine and a vehicle. Background Art

[0002] The SCR mixer is suitable for mixing exhaust gas and urea in the exhaust gas post-processor, so it is required to have a good mixing effect and a small resistance to the gas. In the mixer in the prior art, the lower end of the swirl tube is connected to the inner tube, and the lower end of the inner tube is inserted into the outer tube and connected. The gas will have a temperature drop on the wall of the inner tube and the outer tube, which is easy to cause urea crystallization and affect the exhaust gas post-treatment effect. Utility Model Content

[0003] The utility model aims to provide a cyclone mixer, an exhaust gas post-processor, an engine and a vehicle, so as to solve the problem that crystallization is easy to occur in the mixer and affects the mixing effect and the exhaust gas post-processing effect.

[0004] To achieve this purpose, the utility model adopts the following technical solutions:

[0005] A swirl mixer comprises a cover body and a shell, a cavity is formed between the shell and the cover body, an air inlet and an air outlet are respectively provided at both ends of the cover body along the longitudinal axis, a swirl tube, an inner tube and an outer tube in the cavity, the lower end of the swirl tube is connected to the upper end of the inner tube, and the outer tube is sleeved on the outside of the inner tube; the inner tube and the outer tube are coaxially arranged and an annular channel is provided therebetween, and in the annular channel, a plurality of mesh holes are provided at the upper end of the inner tube, and the plurality of mesh holes are evenly spaced around the circumference of the inner tube to form a mesh section.

[0006] Optionally, the width of the annular channel along the radial direction of the outer tube is 8-12 mm.

[0007] Optionally, a plurality of elongated holes are provided in the middle section of the inner tube, the plurality of elongated holes are evenly spaced along the circumference of the inner tube, and the plurality of elongated holes are arranged in multiple rows along the long axis direction of the inner tube.

[0008] Optionally, the outer side wall of the inner tube is provided with a plurality of connection parts, and the plurality of connection parts are evenly spaced and abut against the inner side wall of the outer tube.

[0009] Optionally, the plurality of connection parts are provided in two groups, each group includes at least two of the connection parts, and the two groups of the connection parts are provided at the upper and lower ends of the inner tube.

[0010] Optionally, the side walls at both ends of the outer tube are provided with connecting holes, and the connecting holes are arranged in a one-to-one correspondence with the connecting parts, and a plurality of the connecting parts can be inserted into the connecting holes and fixed by welding.

[0011] Optionally, a swirl hole is provided on the swirl tube, a swirl plate is provided at the swirl hole, the swirl hole and the swirl plate are both long strips, the swirl plate is connected to the side wall of the swirl hole through a connecting part, and the length of the connecting part is less than the length of the swirl plate.

[0012] Optionally, the swirl sheet is arranged to protrude from the outer side wall of the swirl tube.

[0013] Optionally, the ratio of the length of the swirl blade to the axial length of the inner tube is 1:3-1:5.

[0014] An exhaust gas after-processor comprises the cyclone mixer described in any one of the above embodiments.

[0015] An engine comprises the exhaust gas after-processor.

[0016] A vehicle comprises the engine.

[0017] Beneficial effects of the utility model:

[0018] The cyclone mixer of the utility model is beneficial to heat preservation of the wall surface by arranging an annular channel between the inner tube and the outer tube, thereby increasing the mixing temperature of the gas and urea and improving the exhaust gas treatment effect; by arranging a porous structure at the upper end of the inner tube, the gas inside the inner tube enters the annular channel through the porous structure, which can enhance the collision evaporation and heat exchange of urea particles; the outer tube contacts with the airflow and has good heat preservation performance, which can further reduce the risk of urea crystallization and improve the exhaust gas post-treatment effect.

[0019] The tail gas post-processor of the utility model reduces the risk of urea crystallization by arranging the cyclone mixer provided by the utility model, which is beneficial to improving the tail gas post-processing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a front view of the cyclone mixer provided by the embodiment of the utility model;

[0021] Figure 2 It is a schematic diagram of the exploded structure of the cyclone mixer provided in the embodiment of the utility model;

[0022] Figure 3 It is a schematic diagram of the structure of the inner tube in the cyclone mixer provided in an embodiment of the utility model;

[0023] Figure 4 It is a schematic diagram of the cross-sectional structure of the inner tube and the outer tube in the cyclone mixer provided in an embodiment of the utility model;

[0024] Figure 5 It is a schematic diagram of the structure of a swirl tube in a swirl mixer provided in an embodiment of the utility model.

[0025] In the figure:

[0026] 1. Cover; 11. Air inlet; 12. Air outlet; 2. Shell; 3. Swirl tube; 31. Swirl hole; 32. Swirl sheet; 33. Connecting part; 4. Inner tube; 41. Mesh; 42. Long strip hole; 43. Smooth tube section; 44. Connecting part; 5. Outer tube; 51. Annular channel; 52. Mounting hole. DETAILED DESCRIPTION

[0027] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only the parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0028] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0030] In the description of this embodiment, the terms "upper", "lower", "left", "right" and other directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplified operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation of the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0031] The utility model provides a cyclone mixer, such as Figure 1-Figure 5, including a cover body 1 and a shell body 2, a cavity is formed between the shell body 2 and the cover body 1, an air inlet 11 and an air outlet 12 are respectively provided at both ends of the cover body 1 along the longitudinal axis, a swirl tube 3, an inner tube 4 and an outer tube 5 in the cavity, the lower end of the swirl tube 3 is connected to the upper end of the inner tube 4, and the outer tube 5 is sleeved on the outer side of the inner tube 4; the inner tube 4 and the outer tube 5 are coaxially arranged and an annular channel 51 is provided therebetween, in the annular channel 51, a plurality of mesh holes 41 are provided at the upper end of the inner tube 4, and the plurality of mesh holes 41 are evenly spaced around the circumference of the inner tube 4 to form a mesh section.

[0032] The cyclone mixer of the utility model is advantageous for heat preservation of the wall surface by setting an annular channel 51 between the inner tube 4 and the outer tube 5, ensuring the mixing temperature of the gas and urea, and improving the exhaust gas treatment effect; by setting a porous structure at the upper end of the inner tube 4, the gas inside the inner tube 4 enters the annular channel 51 through the porous structure, which can enhance the collision evaporation and heat exchange of urea particles, and the outer tube 5 is in contact with the airflow, and has good heat preservation performance, which can further reduce the risk of urea crystallization and improve the exhaust gas post-treatment effect. In some embodiments, the outer tube 5 is installed in the cavity by a mounting frame, and the mounting frame divides the cavity into an air inlet cavity and an air outlet cavity, wherein the mesh section is located in the air inlet cavity and the bottom end of the mesh section is lower than the position of the mounting frame, that is, the part of the inner tube 4 located in the air inlet cavity is all mesh sections, so as to increase the heat preservation effect and gas mixing effect in the air inlet cavity, thereby improving the exhaust gas treatment effect.

[0033] Optionally, the width of the annular channel 51 along the radial direction of the outer tube is 8-12 mm, and more preferably 10 mm. Within the width range of the annular channel 51, it is beneficial for the outer tube 5 to fully exchange heat with the inner tube 4, which is beneficial for heating urea and reducing crystallization.

[0034] Optionally, the middle section of the inner tube 4 is provided with a plurality of elongated holes 42 to form an elongated hole section, the plurality of elongated holes 42 are evenly spaced along the circumference of the inner tube 4 , and the plurality of elongated holes 42 are arranged in multiple rows along the long axis direction of the inner tube 4 .

[0035] like Figure 3 As shown, the mesh section is arranged in the upper half of the inner tube 4, the mesh 41 of the mesh section is a circular hole, the width of the elongated hole 42 arranged in the middle section, i.e. the lower half of the inner tube, is not less than the aperture of the mesh 41, and the elongated hole 42 extends along the long axis direction of the inner tube 4. The elongated hole 42 is located in the air outlet cavity, and the elongated hole 42 is conducive to flushing urea and increasing the heat exchange at the lower end, thereby further reducing urea crystallization.

[0036] like Figure 3 As shown, on the inner tube 4, the length of the mesh section is greater than the length of the middle section and is greater than the length of the smooth tube section 43 at the lower end. Preferably, the length of the mesh section is greater than half of the total length of the inner tube 4. The function of the smooth tube section 43 is to increase the structural strength of the lower end of the outer tube 5 and facilitate the installation of the outer tube 5 and the inner tube 4. Therefore, the length of the smooth tube section 43 is relatively small.

[0037] Optionally, the outer side wall of the inner tube 4 is provided with a plurality of connecting portions 44 , and the plurality of connecting portions 44 are evenly spaced and abut against the inner side wall of the outer tube 5 .

[0038] like Figure 2 and Figure 3 As shown, the length of the inner tube 4 is less than that of the outer tube 5, and the inner tube 4 is installed inside the outer tube 5. By providing a connecting portion 44 on the outer wall of the inner tube 4, the inner tube 4 can be connected to the inner wall of the outer tube 5 through the connecting portion 44, which is convenient for installation, and an annular channel 51 is formed between the two, which is beneficial for wall surface insulation. Preferably, multiple connecting portions 44 located at the same axial height are evenly spaced to form an annular channel 51 of uniform width.

[0039] Optionally, the plurality of connection portions 44 are provided in two groups, each group includes at least two connection portions 44 , and the two groups of connection portions 44 are respectively provided at the upper and lower ends of the inner tube 4 .

[0040] like Figure 3 , three connecting parts 44 are arranged at the upper edge of the inner tube 4, and three connecting parts 44 are arranged at the lower edge. The multiple connecting parts 44 at the upper and lower ends are arranged one by one in the axial direction, so as to form an annular channel 51 of uniform width, and the forces between the inner tube 4 and the outer tube 5 are balanced, and the structural stability is good. In some embodiments, the connecting part 44 is formed by bending a metal sheet integrally formed with the inner tube 4, and the connecting part 44 protrudes from the outer wall of the inner tube 4 and the protruding distance is greater than the width of the annular channel 51, so as to pass through the inner wall of the outer tube 5 and limit the width of the annular channel 51.

[0041] Optionally, the side walls at both ends of the outer tube 5 are provided with connecting holes 52 , and the connecting holes 52 are arranged in one-to-one correspondence with the connecting parts 44 , and a plurality of connecting parts 44 can be passed through the connecting holes 52 and fixed by welding.

[0042] like Figure 2 and Figure 3 As shown, the connecting portion 44 is in a rounded V-shape. During installation, the protruding end of the connecting portion 44 is inserted into the connecting hole 52, which is convenient for welding and fixing on the outer wall of the outer tube 5, and is beneficial for axially limiting the installation of the inner tube 4 and the outer tube 5 to avoid axial movement.

[0043] Optionally, a swirl hole 31 is provided on the swirl tube 3, and a swirl plate 32 is provided at the swirl hole 31. The swirl hole 31 and the swirl plate 32 are both long strips. The swirl plate 32 is connected to the side wall of the swirl hole 31 through a connecting portion 33, and the length of the connecting portion 33 is less than the length of the swirl plate 32.

[0044] like Figure 5As shown, the swirl tube 3 is in the shape of a spinal tube, the swirl holes 31 are evenly spaced around the circumference along the outer wall of the swirl tube 3, and the swirl sheets 32 are protruding from the outer wall of the swirl tube 3. The gas swirls under the action of the swirl sheets 32, which increases the mixing uniformity and the gas flow rate and reduces the airflow resistance. The swirl sheets 32 are connected to the side wall of the swirl hole 31 through a smaller connecting portion 33, which is conducive to the airflow diversion at the swirl hole 31, increases the turbulence effect, and improves the mixing uniformity.

[0045] Optionally, the ratio of the length of the swirl blade 32 to the axial length of the inner tube 4 is 1:3-1:5, and more preferably 1:4.

[0046] At a conventional urea injection speed, by reasonably setting the length ratio of the swirl plate 32 to the inner tube 4, the urea can be mixed with the gas as evenly as possible, and can be heated and evaporated again under the action of the annular channel 51, thereby preventing urea crystallization from affecting the exhaust gas treatment effect.

[0047] An exhaust gas after-processor comprises the cyclone mixer of any one of the above embodiments.

[0048] The tail gas post-processor of the utility model reduces the risk of urea crystallization by arranging the cyclone mixer provided by the utility model, which is beneficial to improving the tail gas post-processing effect.

[0049] The cyclone mixer provided by the utility model has a mesh section and a middle section on the inner tube 4, and the middle section is provided with a long strip hole 42, so that the outer tube 5 is always wrapped by the airflow, which has a greater advantage in heat preservation capacity; wherein, the part of the inner tube 4 located in the air outlet cavity is provided with the long strip hole 42, which increases the mixing distance of the gas passing through the long strip hole 42 and the ammonia or urea, is conducive to improving the mixing uniformity and significantly improving the nitrogen oxide conversion efficiency, and improving the exhaust gas treatment effect.

[0050] An embodiment of the present invention further provides an engine, comprising the exhaust gas processor provided above, which has the advantages of low urea crystallization rate, good exhaust gas treatment effect, large exhaust volume, and is beneficial to improving engine performance.

[0051] An embodiment of the present invention also provides a vehicle including the above engine, which has good exhaust gas treatment effect, meets the requirements of current exhaust gas emission standards, and has a large exhaust volume.

[0052] Obviously, the above embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the scope of protection of the present invention. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention shall be included in the scope of protection of the claims of the present invention.

Claims

1. A cyclone mixer, comprising a cover (1) and a shell (2), wherein a cavity is formed between the shell (2) and the cover (1), wherein the cover (1) is provided with an air inlet (11) and an air outlet (12) at both ends along the longitudinal axis, respectively, and wherein a cyclone tube (3), an inner tube (4) and an outer tube (5) are provided in the cavity, wherein the lower end of the cyclone tube (3) is connected to the upper end of the inner tube (4), and the outer tube (5) is sleeved on the outer side of the inner tube (4); characterized in that: The inner tube (4) and the outer tube (5) are coaxially arranged with an annular channel (51) therebetween. In the annular channel (51), a plurality of mesh holes (41) are arranged at the upper end of the inner tube (4). The plurality of mesh holes (41) are evenly spaced around the circumference of the inner tube (4) to form mesh sections.

2. The cyclone mixer according to claim 1, characterized in that: The width of the annular channel (51) along the radial direction of the outer tube (5) is 8-12 mm.

3. The cyclone mixer according to claim 2, characterized in that: The middle section of the inner tube (4) is provided with a plurality of elongated holes (42), the plurality of elongated holes (42) are evenly spaced along the circumference of the inner tube (4), and the plurality of elongated holes (42) are arranged in multiple rows along the long axis direction of the inner tube (4).

4. The cyclone mixer according to claim 1, characterized in that: The outer side wall of the inner tube (4) is provided with a plurality of connection parts (44), and the plurality of connection parts (44) are evenly spaced and connected to the inner side wall of the outer tube (5).

5. The cyclone mixer according to claim 4, characterized in that: The plurality of connection parts (44) are provided in two groups, each group comprising at least two connection parts (44), and the two groups of connection parts (44) are respectively provided at the upper and lower ends of the inner tube (4).

6. The cyclone mixer according to claim 4, characterized in that: The side walls at both ends of the outer tube (5) are provided with connection holes (52), and the connection holes (52) are arranged in a one-to-one correspondence with the connection parts (44). A plurality of the connection parts (44) can be inserted into the connection holes (52) and fixed by welding.

7. The cyclone mixer according to claim 1, characterized in that: The swirl tube (3) is provided with a swirl hole (31), and a swirl sheet (32) is provided at the swirl hole (31). The swirl hole (31) and the swirl sheet (32) are both in the shape of long strips. The swirl sheet (32) is connected to the side wall of the swirl hole (31) via a connecting portion (33), and the length of the connecting portion (33) is less than the length of the swirl sheet (32).

8. The cyclone mixer according to claim 7, characterized in that: The swirl sheet (32) is arranged to protrude from the outer side wall of the swirl tube (3).

9. The cyclone mixer according to claim 7, characterized in that: The ratio of the length of the swirl sheet (32) to the axial length of the inner tube (4) is 1:3-1:

5.

10. Exhaust gas after-processor, characterized in that: The invention comprises a cyclone mixer according to any one of claims 1 to 9.

11. An engine, characterized in that Including the exhaust gas after-processor according to claim 10.

12. A vehicle, characterized in that Comprising the engine as claimed in claim 11.

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