CN217681931U

CN217681931U - Urea solution mixer, engine aftertreatment system and vehicle

Info

Publication number: CN217681931U
Application number: CN202221805616.2U
Authority: CN
Inventors: 薛裕丹; 李健巍; 张素英; 郑茜
Original assignee: Weichai Power Co Ltd
Current assignee: Weichai Power Co Ltd
Priority date: 2022-07-13
Filing date: 2022-07-13
Publication date: 2022-10-28
Anticipated expiration: 2032-07-13

Abstract

The utility model relates to the technical field of vehicles, a urea solution blender is disclosed, engine aftertreatment system and vehicle, at engine during operation, high temperature tail gas passes through in the inlet port entering tail gas passageway of tail gas passageway axial one end, the urea nozzle sprays urea in to the hybrid channel through the toper opening simultaneously, high temperature tail gas passes through the opening of the tail gas passageway axial other end and gets into in the toper open-ended marginal zone from toper open-ended big footpath end opening, and realize the mixture of urea and high temperature tail gas in toper opening and hybrid channel, can avoid toper open-ended marginal zone to form the backward flow blind spot, in order to prevent that toper open-ended inner wall from forming the urea crystallization, atomization effect has still been improved.

Description

Urea solution mixer, engine aftertreatment system and vehicle

Technical Field

The utility model relates to the technical field of vehicles, especially, relate to a urea solution blender, engine aftertreatment system and vehicle.

Background

Selective Catalytic Reduction (SCR) refers to a technique for reducing NOx in flue gas selectively to non-toxic N2 and H2O by using a reducing agent (ammonia, urea, hydrocarbon, etc.) under a certain temperature range and a catalyst.

The catalyst is the most critical part of the SCR system, and the activity of the catalyst is a measure of the rate at which the catalyst accelerates the NOx reduction reaction. The higher the activity of the catalyst is, the faster the reaction rate is, the higher the efficiency of removing NOx is, and the activity of the catalyst is affected by the components of the catalyst, the urea solution mixer which evaporates the urea solution and mixes with air, the flue gas temperature, the flue gas components and other factors.

For the current urea solution mixer, the urea solution mixer comprises a nozzle mounting seat, a urea nozzle and a mixing pipeline, wherein a mounting channel is arranged on the nozzle mounting seat, one end of the urea nozzle is inserted into the mounting channel, the mixing pipeline is mounted on the nozzle mounting seat, and one end of the mixing pipeline is communicated with the other end of the mounting channel. The urea nozzle sprays urea and sprays into the mixing pipeline from the installation channel, and simultaneously the high-temperature tail gas of the engine is introduced into the mixing pipeline from the circumferential side wall of the mixing pipeline, and the high-temperature tail gas and the urea are mixed to form urea spray.

However, in actual operation, the installation channel and the mixing pipeline are coaxial, urea is sprayed into the mixing pipeline along the axial direction of the installation channel, and high-temperature tail gas is introduced into the mixing pipeline from the circumferential side wall of the mixing pipeline. A small amount of high-temperature tail gas overflows from the edge part of one end of the mixing pipeline close to the urea nozzle and directly impacts the urea nozzle, so that the urea nozzle is easily damaged by high-temperature waste gas. For this purpose, it is proposed to provide a divergent cone opening at the end of the installation channel adjoining the mixing duct, so that the high-temperature exhaust gases which overflow from the edge of the mixing duct at the end close to the urea nozzle enter the edge region of the cone opening without directly impacting the urea nozzle.

However, in practical applications, it is found that after the tapered opening is provided, backflow is easily generated in the edge area of the tapered opening, so that urea droplets with small particle size form urea crystals on the inner surface of the tapered opening, and when the urea crystals are serious, the urea spray cone angle and the urea atomization effect are affected, and even the spray hole of the urea nozzle is blocked.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a urea solution blender, engine aftertreatment system and vehicle can avoid the air current to form the urea crystallization at the internal surface of nozzle mount pad.

To achieve the purpose, the utility model adopts the following technical proposal:

a urea solution mixer comprises a nozzle mounting seat, wherein a mounting channel for mounting a urea nozzle is arranged on the nozzle mounting seat, and one end of the mounting channel is provided with a tapered opening which is gradually enlarged and a mounting hole which is connected with and coaxial with the large-diameter end of the tapered opening;

still include the water conservancy diversion structure, the water conservancy diversion structure includes:

the guide sleeve is provided with a mixing channel extending along the axial direction of the guide sleeve, and one end of the mixing channel is communicated with the conical opening;

connection structure, the one end of water conservancy diversion cover is inserted in the mounting hole, and pass through connection structure is fixed in the nozzle mount pad, the periphery wall of water conservancy diversion cover with form axial both ends open-ended tail gas passageway between the internal perisporium of mounting hole, the one end opening of tail gas passageway forms the air inlet, the opening of the other end with toper open-ended big footpath end opening directly communicates.

As a preferable technical solution of the urea solution mixer, an aperture of an opening of the exhaust gas channel near one end of the tapered opening is larger than an aperture of a large-diameter end of the tapered opening.

As a preferable technical solution of the above urea solution mixer, the flow guide sleeve includes:

the at least two guide plates are sequentially arranged at intervals along the circumferential direction of the at least two guide plates and are connected to form the mixing channel.

As a preferable technical solution of the urea solution mixer, the outer surface of the guide plate is a conical surface.

As a preferable embodiment of the urea solution mixer, each of the guide plates is provided with one of the connection structures, and the connection structure includes:

and the adjacent edges of each guide plate and the other guide plate are turned outwards to form one turn-ups, and the adjacent two guide plates are connected through the turn-ups.

As a preferable technical solution of the above urea solution mixer, the connection structure further includes:

the engaging lug, the engaging lug is followed the circumference of guide plate extend and with the periphery wall of guide plate is just setting up to the interval, the engaging lug passes through the turn-ups with the guide plate links to each other, the engaging lug with the nozzle mount pad links to each other.

As a preferable technical solution of the above urea solution mixer, opposite ends of the flange are connected to the baffle and the engaging lug, respectively.

As a preferred technical solution of the above urea solution mixer, the length of the connecting structure along the axial direction of the flow guide sleeve is smaller than the axial length of the flow guide sleeve;

the guide sleeve is provided with a communicating hole for communicating the mixed channel with the tail gas channel, and the communicating hole is positioned at one end of the connecting structure back to the conical opening.

The utility model also provides an engine post-treatment system, which comprises a urea nozzle and the urea solution mixer according to any one of the above schemes; the mounting channel further comprises a mounting hole, and the mounting hole is connected with the large-diameter end of the conical opening and is coaxial with the conical opening;

one end of the urea nozzle is inserted into and fixed in the assembling hole, and the urea nozzle is used for spraying urea into the mixing channel through the conical opening.

The utility model also provides a vehicle, including foretell engine aftertreatment system.

The utility model discloses beneficial effect: the utility model provides a urea solution blender, engine aftertreatment system and vehicle, at engine during operation, high temperature tail gas passes through in the inlet port entering tail gas channel of tail gas channel axial one end, the urea nozzle passes through the toper opening and sprays urea in to the hybrid channel simultaneously, high temperature tail gas passes through the opening of the tail gas channel axial other end and gets into in the toper open-ended marginal zone from toper open-ended major diameter end opening, and realize the mixture of urea and high temperature tail gas in toper opening and hybrid channel, can avoid toper open-ended marginal zone to form the backward flow blind spot, in order to prevent that toper open-ended inner wall from forming the urea crystallization, atomization effect has still been improved.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required to be used in the description of the embodiments of the present invention will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the contents of the embodiments of the present invention and the drawings without creative efforts.

Fig. 1 is a cross-sectional view of a urea solution mixer provided by an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a flow guiding structure provided in an embodiment of the present invention.

In the figure:

1. a flow guide structure; 11. a flow guide sleeve; 111. a mixing channel; 112. a communicating hole;

12. a connecting structure; 121. flanging; 122. connecting lugs;

2. a tail gas channel;

3. a nozzle mount; 31. an assembly hole; 32. a conical opening.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

In the description of the present invention, unless expressly stated or limited otherwise, the terms "connected," "connected," and "fixed" are to be construed broadly, e.g., as meaning permanently connected, detachably connected, or integral to one another; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.

In the present disclosure, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact between the first and second features, or may comprise contact between the first and second features not directly. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

In the description of the present embodiment, the terms "upper", "lower", "right", etc. are used in an orientation or positional relationship based on that shown in the drawings only for convenience of description and simplicity of operation, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first" and "second" are used only for descriptive purposes and are not intended to have a special meaning.

As shown in fig. 1 and 2, the present embodiment provides a urea solution mixer, an engine after-treatment system vehicle, wherein the engine after-treatment system is used for the vehicle to perform purification treatment on engine exhaust. The engine aftertreatment system comprises a urea nozzle and a urea solution mixer, the urea solution mixer comprises a nozzle mounting seat 3 and a flow guide structure 1, a mounting channel is arranged on the nozzle mounting seat 3, one end of the urea nozzle is inserted into and fixed in the mounting channel, the urea nozzle is used for spraying urea solution to the flow guide structure 1 through the other end of the mounting channel, and the flow guide structure 1 is used for mixing the urea solution sprayed into the urea nozzle with high-temperature tail gas generated by the work of an engine so as to atomize the urea.

Specifically, one end of the mounting passage is provided with a tapered opening 32, a mounting hole connected and coaxial with a large-diameter end of the tapered opening 32, and a fitting hole 31 connected and coaxial with a small-diameter end of the tapered opening 32, wherein one end of the urea nozzle is inserted and fixed into the fitting hole 31.

The flow guide structure 1 comprises a flow guide sleeve 11 and a connecting structure 12, wherein a mixing channel 111 extending along the axial direction of the flow guide sleeve 11 is arranged on the flow guide sleeve 11, and one end of the mixing channel 111 is communicated with the conical opening 32; one end of the flow guide sleeve 11 is inserted into the mounting hole and is fixed on the nozzle mounting base 3 through the connecting structure 12, a tail gas channel 2 with two axial end openings is formed between the outer peripheral wall of the flow guide sleeve 11 and the inner peripheral wall of the mounting hole, one end opening of the tail gas channel 2 forms an air inlet, and the opening of the other end is communicated with the conical opening 32.

When the engine works, high-temperature tail gas enters the tail gas channel 2 through the air inlet hole at one axial end of the tail gas channel 2, the urea nozzle sprays urea into the mixing channel 111 through the conical opening 32, the high-temperature tail gas enters the edge area of the conical opening 32 from the large-diameter end opening of the conical opening 32 through the opening at the other axial end of the tail gas channel 2, the mixing of the urea and the high-temperature tail gas is realized in the conical opening 32 and the mixing channel 111, the backflow dead area formed in the edge area of the conical opening 32 can be avoided, the urea crystal is prevented from being formed on the inner wall of the conical opening 32, and the atomization effect is also improved.

Alternatively, the mounting hole is connected to the large-diameter end of the tapered opening 32 to form a step surface, and after the flow guide sleeve 11 is inserted into the mounting hole, the connecting structure 12 abuts against the step surface. Optionally, the aperture of the end of the tail gas channel 2 close to the tapered opening 32 is larger than the aperture of the large-diameter end of the tapered opening 32, so that an airflow dead zone can be effectively prevented from being formed at a position where the axial end surface of the flow guide sleeve 11 is connected with the inner wall of the tapered opening 32.

Further, the flow guide sleeve 11 includes at least two flow guide plates, and the at least two flow guide plates are sequentially arranged at intervals along the circumferential direction and connected to enclose the mixing channel 111. Exemplarily, the outer surface of the guide plate is a conical surface, and the conical surface is used for guiding the high-temperature tail gas to enable the high-temperature tail gas to be sprayed out from the small-diameter end along the outer peripheral surface of the guide sleeve 11, so that the high-temperature tail gas has a good turbulence effect when encountering the urea flowing reversely, the atomization effect of the urea is greatly improved, and the urea is prevented from crystallizing and blocking the nozzle.

Furthermore, each guide plate is provided with a connecting structure 12, the connecting structure 12 comprises a flange 121, the edge of each guide plate adjacent to the other guide plate is turned outwards to form a flange 121, and two adjacent guide plates are connected through the flange 121 to realize the connection between the two adjacent guide plates.

Further, connection structure 12 still includes engaging lug 122, and engaging lug 122 extends and sets up just to the interval with the periphery wall of guide plate along the circumference of guide plate, and engaging lug 122 passes through turn-ups 121 and links to each other with the guide plate, and engaging lug 122 links to each other with nozzle mount pad 3. With this arrangement, it is possible to avoid as much as possible the formation of a backflow dead zone where the connecting structure 12 meets the tapered opening 32.

In this embodiment, the engaging lug 122 is welded and fixed with the nozzle mounting base 3, and the flanges 121 of two adjacent guide plates are welded and fixed, so that the connecting mode is simple, the cost is low, and the stability is good.

Alternatively, the opposite ends of the flanges 121 are connected to the flow guiding plate and the connecting lug 122 respectively, so that the space between the flow guiding plate and the connecting lug 122 forms a part of the exhaust gas passage 2, and the backflow dead zone is avoided as much as possible at the position where the connecting structure 12 meets the tapered opening 32.

Further, the length of the connecting structure 12 along the axial direction of the flow guide sleeve 11 is less than the axial length of the flow guide sleeve 11; the flow guiding sleeve 11 is provided with a communicating hole 112 for communicating the mixing channel 111 and the tail gas channel 2, and the communicating hole 112 is located at one end of the connecting structure 12, which is back to the conical opening 32. By the arrangement, part of high-temperature tail gas can be fed into the tail gas channel 2 through the communicating hole 112, so that the mixing effect of urea and the high-temperature tail gas is improved, and urea is prevented from crystallizing on the inner wall of the mixing channel 111; and simultaneously, the flow guiding effect of the flow guiding sleeve 11 is improved.

The urea solution mixer provided by the embodiment can be applied to engines with different discharge capacities, the size of the flow guide structure 1 can be reasonably adjusted according to the post-treatment requirements of different specifications, the matching with the discharge capacity of the engine is realized, and the urea solution mixer is simple in structure, low in cost and high in reliability.

In addition, the foregoing is only the preferred embodiment of the present invention and the technical principles applied thereto. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail with reference to the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the scope of the present invention.

Claims

1. A urea solution mixer comprises a nozzle mounting seat (3), wherein a mounting channel for mounting a urea nozzle is arranged on the nozzle mounting seat (3), and one end of the mounting channel is provided with a tapered opening (32) which is gradually enlarged and a mounting hole which is connected with and coaxial with the large-diameter end of the tapered opening (32);

the utility model is characterized in that, still include water conservancy diversion structure (1), water conservancy diversion structure (1) includes:

the flow guide sleeve (11) is provided with a mixing channel (111) extending along the axial direction of the flow guide sleeve (11), and one end of the mixing channel (111) is communicated with the conical opening (32);

connection structure (12), the one end of water conservancy diversion cover (11) is inserted in the mounting hole, and pass through connection structure (12) are fixed in nozzle mount pad (3), the periphery wall of water conservancy diversion cover (11) with form axial both ends open-ended tail gas passageway (2) between the internal perisporium of mounting hole, the one end opening of tail gas passageway (2) forms the air inlet, the opening of the other end with the big footpath end opening of toper opening (32) directly communicates.

2. A urea solution mixer according to claim 1, characterized in that the diameter of the opening of the exhaust channel (2) near the end of the conical opening (32) is larger than the diameter of the larger diameter end of the conical opening (32).

3. A urea solution mixer according to claim 1, characterized in that the flow guiding sleeve (11) comprises:

the at least two guide plates are sequentially arranged at intervals along the circumferential direction of the at least two guide plates and are connected to form the mixing channel (111).

4. A urea solution mixer according to claim 3, characterised in that the outer surface of the deflector is conical.

5. A urea solution mixer according to claim 3, characterized in that each of said baffles is provided with one of said connection structures (12), said connection structure (12) comprising:

and the adjacent edge of each guide plate and the other guide plate is turned outwards to form one turn-up edge (121), and the two adjacent guide plates are connected through the turn-up edge (121).

6. Urea solution mixer according to claim 5, characterized in that the connection structure (12) further comprises:

engaging lug (122), engaging lug (122) are followed the circumference of guide plate extend and with the periphery wall of guide plate is just to the interval setting, engaging lug (122) pass through turn-ups (121) with the guide plate links to each other, engaging lug (122) with nozzle mount pad (3) link to each other.

7. Urea solution mixer according to claim 6, characterized in that the opposite ends of the turn-up (121) are connected to the baffle and the connection lug (122), respectively.

8. Urea solution mixer according to claim 6, characterized in that the length of the connection structure (12) in the axial direction of the guide sleeve (11) is smaller than the axial length of the guide sleeve (11);

the flow guide sleeve (11) is provided with a communicating hole (112) for communicating the mixing channel (111) with the tail gas channel (2), and the communicating hole (112) is located at one end, back to the conical opening (32), of the connecting structure (12).

9. An engine aftertreatment system comprising a urea nozzle and a urea solution mixer according to any one of claims 1 to 8; the mounting channel further comprises a mounting hole (31), the mounting hole (31) is connected with the large-diameter end of the conical opening (32) and is coaxial with the conical opening (32);

one end of the urea nozzle is inserted into and fixed in the assembly hole (31), and the urea nozzle is used for spraying urea into the mixing channel (111) through a conical opening (32).

10. A vehicle comprising the engine aftertreatment system of claim 9.