CN113914976B

CN113914976B - Engine and aftertreatment mixer thereof

Info

Publication number: CN113914976B
Application number: CN202111345101.9A
Authority: CN
Inventors: 龙远; 王科星; 黄凯; 闫寒; 朱光贞
Original assignee: FAW Jiefang Automotive Co Ltd
Current assignee: FAW Jiefang Automotive Co Ltd
Priority date: 2021-11-15
Filing date: 2021-11-15
Publication date: 2023-02-17
Anticipated expiration: 2041-11-15
Also published as: CN113914976A

Abstract

The invention relates to an engine and an aftertreatment mixer thereof, the aftertreatment mixer comprising: a housing having an interior cavity; the clapboard is fixed in the shell and divides the inner cavity into an air inlet cavity and an air outlet cavity; the cyclone tube is accommodated in the air inlet cavity, a first cyclone inlet and a second cyclone inlet which are different in axial position are arranged on the peripheral side of the cyclone tube, the second cyclone inlet is closer to the partition plate than the first cyclone inlet, and the opening of the first cyclone inlet is larger than that of the second cyclone inlet; the mixing pipe comprises an inner layer pipe and an outer layer pipe, the outer layer pipe is accommodated in the air outlet cavity and connected with the cyclone pipe, and the inner layer pipe is accommodated in the cyclone pipe and connected with the outer layer pipe; when the airflow flows to the cyclone tube from the air inlet cavity, the air inflow of the first cyclone inlet is larger than that of the second cyclone inlet. An engine includes the aftertreatment mixer described above. The engine and the aftertreatment mixer have the advantages of low energy consumption and high conversion efficiency of nitrogen oxides.

Description

Engine and aftertreatment mixer thereof

Technical Field

The invention relates to the technical field of automobile exhaust treatment, in particular to an engine and an aftertreatment mixer thereof.

Background

The tail gas discharged by the diesel engine mainly contains harmful gases such as nitrogen oxides, hydrocarbons, carbon monoxide and the like, and the post-treatment device of the diesel engine mainly has the function of purifying the discharged harmful gases. At present, oxidative catalyst (DOC), particulate filter (DPF) and Selective Catalytic Reduction (SCR) technologies are often adopted by diesel engines to treat exhaust pollutants, so that exhaust emission meets the limit requirements of national six emission regulations.

In the selective catalytic reduction technology, mostly, the exhaust gas is subjected to catalytic reduction treatment through an aftertreatment mixer, the discharged exhaust gas enters the aftertreatment mixer, the urea solution is mixed with the exhaust gas through spraying the urea solution in the mixer, and nitrogen oxides in the exhaust gas are catalytically reduced into ammonia gas and then discharged, so that the emission of the exhaust gas meets the requirement of the regulation limit.

However, the existing aftertreatment mixer for the diesel engine generally has the defects of low gas-liquid mixing uniformity, high back pressure, low nitrogen oxide conversion efficiency and high energy consumption.

Disclosure of Invention

In view of the above, it is necessary to provide an engine and an aftertreatment mixer thereof, which are aimed at the problems of low nitrogen oxide conversion efficiency and large energy consumption of the existing aftertreatment mixer.

An aftertreatment mixer, comprising:

a housing having an interior cavity;

the clapboard is fixed in the shell and divides the inner cavity into an air inlet cavity and an air outlet cavity;

the cyclone tube is accommodated in the air inlet cavity, a first cyclone inlet and a second cyclone inlet which are different in axial position are arranged on the peripheral side of the cyclone tube, the second cyclone inlet is closer to the partition plate than the first cyclone inlet, and the opening of the first cyclone inlet is larger than that of the second cyclone inlet;

the mixing pipe comprises an inner layer pipe and an outer layer pipe, the outer layer pipe is accommodated in the air outlet cavity and connected with the cyclone pipe, and the inner layer pipe is accommodated in the cyclone pipe and connected with the outer layer pipe;

when the air flow flows to the spiral-flow pipe from the air inlet cavity, the air inflow of the first spiral-flow inlet is larger than that of the second spiral-flow inlet, the air flow uniformly flows into the inner-layer pipe from the spiral-flow pipe and is mixed with urea solution, and the mixed air flow is discharged from the outer-layer pipe and the air outlet cavity.

According to the post-treatment mixer, the opening area of the first rotational flow inlet is increased in a limited space, and the air inflow flowing into the rotational flow pipe from the first rotational flow inlet in unit time is increased, so that the back pressure value of the post-treatment mixer is effectively reduced, and the energy consumption is reduced; meanwhile, the axial position of the first cyclone inlet is higher than that of the second cyclone inlet, and the air inflow of the first cyclone inlet is larger than that of the second cyclone inlet, so that the cyclone path of the airflow flowing into the cyclone tube is lengthened, the uniformity of airflow distribution in the cyclone tube is facilitated, the mixing effect of the airflow and the solution in the subsequent cyclone tube is improved, and the conversion efficiency of nitrogen oxides in the airflow is improved.

In one embodiment, a first swirl hole and a second swirl hole which are different in axial position are arranged on the circumferential side of the swirl tube, a first swirl plate is arranged on one side of the first swirl hole, the first swirl inlet is defined by the first swirl plate and the first swirl hole, a second swirl inlet is defined by the second swirl plate and the second swirl hole.

In one embodiment, the first swirl plate extends obliquely outwards from one side edge of the first swirl hole, the second swirl plate extends obliquely outwards from one side edge of the second swirl hole, and the inclination directions of the first swirl plate and the second swirl plate are consistent.

In one embodiment, the axial size of the first swirl hole is larger than that of the second swirl hole, and the radial size of the first swirl hole is equal to that of the second swirl hole.

In one embodiment, the first swirler plate has an axial dimension smaller than an axial dimension of the first swirler hole, and the second swirler plate has an axial dimension smaller than an axial dimension of the second swirler hole.

In one embodiment, the cyclone tube further comprises an air inlet baffle plate with a plurality of air inlet holes, wherein the air inlet baffle plate is contained in the air inlet cavity and covers the cyclone tube.

In one embodiment, the air inlet baffle is semi-cylindrical, and the axial size of the air inlet hole is smaller than the axial sizes of the first swirl hole and the second swirl hole.

In one embodiment, the gas outlet baffle plate further comprises a plurality of gas outlet holes, and the gas outlet baffle plate is connected to the shell and partially covers the opening of the gas outlet cavity.

In one embodiment, the opening of the air outlet cavity is circular, and the air outlet baffle is semicircular.

In one embodiment, the device further comprises a blocking cover with a plurality of vent holes and a spoiler with a plurality of pressure reduction holes, the blocking cover is arranged at the end part of the outer layer pipe far away from the inner layer pipe, and the spoiler is obliquely arranged outside the blocking cover.

In one embodiment, the spoiler is W-shaped, the housing is provided with a slot, and the spoiler is provided with a protrusion to be clamped in the slot.

In one embodiment, the device further comprises a mounting seat and a nozzle, wherein the mounting seat is arranged on the top side of the shell, and the nozzle is mounted on the mounting seat and used for spraying the solution into the inner layer pipe.

In one embodiment, the inner-layer pipe comprises a first cyclone section, a transition section and a second cyclone section which are connected, the solution is sprayed to the first cyclone section, a plurality of cyclone holes are formed in the first cyclone section and the second cyclone section, and the transition section is smooth and is not provided with the cyclone holes.

In one embodiment, the method further comprises at least one of the following steps:

the cyclone tube is in a round table hollow shape, and the diameter of the cyclone tube is increased in an axial direction;

the outer layer pipe is provided with a plurality of first holes, and the diameter of the outer layer pipe is larger than that of the inner layer pipe;

the shell comprises an inner shell, an outer shell and an end cover, wherein the end cover is connected with the inner shell and is formed into a whole, and the outer shell is connected with the end cover through a reinforcing plate.

An engine comprising the aftertreatment mixer described above.

The engine effectively reduces the back pressure value of the aftertreatment mixer so as to reduce energy consumption, and the conversion efficiency of nitrogen oxides is high.

Drawings

FIG. 1 is a schematic diagram of an aftertreatment mixer in one embodiment;

FIG. 2 is a partial schematic view of the aftertreatment mixer of FIG. 1 (illustrating the intake baffles);

FIG. 3 is a partial schematic view of the aftertreatment mixer of FIG. 1 (without the intake baffles);

FIG. 4 is a side view of the aftertreatment mixer of FIG. 1;

FIG. 5 is an exploded view of the aftertreatment mixer of FIG. 1;

FIG. 6 is a schematic view of a cyclone in the aftertreatment mixer of FIG. 1;

FIG. 7 is a schematic view of an inner tube of the aftertreatment mixer of FIG. 1.

Reference numerals:

100. a housing; 101. an inner cavity; 102. an air inlet cavity; 103. an air outlet cavity; 110. an inner housing; 120. an outer housing; 130. an end cap; 140. a reinforcing plate; 200. a partition plate; 300. a swirl tube; 301. a first swirl inlet; 302. a second swirl inlet; 310. a first swirl hole; 320. a second swirl hole; 330. a first spinning disk; 340. a second spinning disk; 400. a mixing tube; 410. an inner layer tube; 411. a first cyclone section; 412. a transition section; 413. a second cyclone section; 414. a swirl hole; 415. a first flanging; 416. second flanging; 420. an outer tube; 421. a first hole; 500. an intake baffle; 501. an air inlet; 502. a first air intake hole; 503. a second air intake hole; 600. an air outlet baffle; 601. an air outlet; 700. blocking the cover; 800. a spoiler; 801. a pressure reduction well; 802. a protrusion; 900. and (7) mounting a seat.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood according to specific situations by those of ordinary skill in the art.

In the present invention, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may be directly contacting the second feature or the first and second features may be indirectly contacting each other through intervening media. Also, a first feature "on," "above," and "over" a second feature may be directly on or obliquely above the second feature, or simply mean that the first feature is at a higher level than the second feature. A first feature "under," "beneath," and "under" a second feature may be directly under or obliquely under the second feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. As used herein, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are for purposes of illustration only and do not denote a single embodiment.

In the selective catalytic reduction technology, mostly, the exhaust gas is subjected to catalytic reduction treatment through an aftertreatment mixer, the discharged exhaust gas enters the aftertreatment mixer, the urea solution is mixed with the exhaust gas through spraying the urea solution in the mixer, and nitrogen oxides in the exhaust gas are catalytically reduced into ammonia gas and then discharged, so that the emission of the exhaust gas meets the requirement of the regulation limit. However, the existing aftertreatment mixer for the diesel engine generally has the defects of low gas-liquid mixing uniformity, high back pressure, low nitrogen oxide conversion efficiency and high energy consumption.

Here, the back pressure refers to a pressure that is applied in a direction opposite to the moving direction when the outside air flows into the aftertreatment mixer and then flows in the aftertreatment mixer, and is blocked by an obstacle or a curve. The higher the back pressure value, the more external energy consumption is consumed.

Based on the above considerations, the inventors have conducted extensive studies, and as a result, the present application has devised an aftertreatment mixer for an engine, which has high nox conversion efficiency and low energy consumption.

Referring to fig. 1 and 2, an embodiment of an aftertreatment mixer includes a housing 100, a baffle 200, a swirl tube 300, and a mixing tube 400. Referring to fig. 3, the housing 100 has an inner cavity 101, and a partition 200 is fixed in the housing 100 and divides the inner cavity 101 into an inlet cavity 102 and an outlet cavity 103. The cyclone tube 300 is accommodated in the air inlet cavity 102, a first cyclone inlet 301 and a second cyclone inlet 302 which are different in axial position are arranged on the peripheral side of the cyclone tube 300, the second cyclone inlet 302 is closer to the partition plate 200 than the first cyclone inlet 301, and the opening of the first cyclone inlet 301 is larger than that of the second cyclone inlet 302. The mixing tube 400 includes an inner tube 410 and an outer tube 420, the outer tube 420 is received in the outlet chamber 103 and connected to the swirl tube 300, and the inner tube 410 is received in the swirl tube 300 and connected to the outer tube 420.

Referring to fig. 4, when the airflow flows from the air inlet cavity 102 to the cyclone tube 300, the air inflow of the first cyclone inlet 301 is greater than the air inflow of the second cyclone inlet 302, the airflow uniformly swirls through the cyclone tube 300 and flows into the inner tube 410 to be mixed with the urea solution, and the mixed airflow is discharged through the outer tube 420 and the air outlet cavity 103.

Through the arrangement, the opening area of the first cyclone inlet 301 is increased in a limited space, and the air inflow flowing into the cyclone pipe 300 from the first cyclone inlet 301 in unit time is increased, so that the back pressure value of the aftertreatment mixer is effectively reduced, and the energy consumption is reduced; meanwhile, because the axial position of the first cyclone inlet 301 is higher than the axial position of the second cyclone inlet 302, the air inflow of the first cyclone inlet 301 is larger than that of the second cyclone inlet 302, so that most of air flows flowing into the cyclone tube 300 can be lengthened, the distribution uniformity of the air flows in the cyclone tube 300 is facilitated, the mixing effect of the air flows and solutions in the subsequent cyclone tube 300 is improved, and the conversion efficiency of nitrogen oxides in the air flows is improved.

Here, the gas flow is exhaust gas discharged from an engine, and the solution is a urea solution.

In the embodiment shown in fig. 3, the swirl tube 300 is provided with a first swirl hole 310 and a second swirl hole 320 at different axial positions on the circumferential side. Referring to fig. 6, a first swirler plate 330 is disposed at one side of the first swirler hole 310, and the first swirler inlet 301 is defined by the first swirler plate 330 and the first swirler hole 310. A second swirl hole 320 is formed at one side of the second swirl hole 340, and the second swirl inlet 302 is defined by the second swirl hole 320 and the second swirl plate 340.

In this embodiment, the axial position of the first swirl holes 310 is higher than the axial position of the second swirl holes 320, and the axial position of the first swirl plate 330 is higher than the axial position of the second swirl plate 340. Through the above arrangement, the airflow in the air intake cavity 102 can flow into the cyclone tube 300 through the corresponding cyclone holes 414 respectively under the guiding action of the first cyclone sheet 330 and the second cyclone sheet 340, and the airflow is favorably orderly and uniformly flowed.

Specifically, referring to fig. 6, the first swirl plate 330 extends obliquely outward from a side edge of the first swirl hole 310, the second swirl plate 340 extends obliquely outward from a side edge of the second swirl hole 320, and the first swirl plate 330 and the second swirl plate 340 are inclined in the same direction.

Through this setting, the incline direction of each spinning disk is unanimous, and the air current all is to same direction water conservancy diversion, avoids appearing the phenomenon of turbulent flow or turbulent flow because of spinning disk incline direction inconsistent.

In this embodiment, the first swirler plate 330 extends obliquely outward from the right edge of the first swirl hole 310, and the second swirler plate 340 extends obliquely outward from the right edge of the second swirl hole 320, so that each swirler plate has a right-handed shape, thereby ensuring that the swirling direction of the airflow passing through the swirler tube 300 is all right-handed. In other embodiments, the first swirl plate 330 and the second swirl plate 340 can also be left-handed, so that the airflow direction is left-handed.

As shown in fig. 6, the axial size of the first swirl holes 310 is greater than the axial size of the second swirl holes 320, and the radial size of the first swirl holes 310 is equal to the radial size of the second swirl holes 320.

Through this setting, on the basis that keeps first whirl hole 310 and second whirl hole 320 radial dimension the same, increase the axial dimension of first whirl hole 310 to increase the open area of first whirl hole 310, thereby do benefit to the even whirl of air current to cyclone tube 300 when reducing the backpressure.

Here, the axial dimension refers to the dimension in the X direction shown in fig. 3, and the radial dimension refers to the dimension in the Y direction shown in fig. 3.

Further, as shown in FIG. 6, the axial dimension of the first swirler plate 330 is smaller than the axial dimension of the first swirler hole 310, and the axial dimension of the second swirler plate 340 is smaller than the axial dimension of the second swirler hole 320.

Through this setting, make the spinning disk have the effect of water conservancy diversion, reduce the hindrance of spinning disk to the air current simultaneously, reduce the backpressure and do benefit to the even whirl of air current.

In this embodiment, as shown in fig. 6, the first cyclone holes 310 and the second cyclone holes 320 are both in the shape of a strip, and correspondingly, the first cyclone plate and the second cyclone plate are also in the shape of a strip, so as to facilitate the flow guiding of the air flow. In other embodiments, the first swirl holes 310 and the second swirl holes 320 may be circular or have other shapes, and the first swirl plate and the second swirl plate may be square or have other shapes.

In this embodiment, as shown in fig. 6, the number of the first swirl holes 310 and the number of the second swirl holes 320 are both multiple, the first swirl holes 310 are distributed along the circumferential side of the swirl tube 300 at intervals, the size shape and the axial position of the first swirl holes 310 are the same, the second swirl holes 320 are distributed along the circumferential side of the swirl tube 300 at intervals, and the size shape and the axial position of the second swirl holes 320 are the same, which is favorable for ensuring the uniformity of the swirling flow of the air flow. In other embodiments, the plurality of first swirl holes 310 may be arranged to be offset in size and shape and in axial position, and the plurality of second swirl holes 320 may be arranged to be offset in size and shape and in axial position.

In the present embodiment, as shown in fig. 6, the swirl tube 300 is hollow in a circular truncated cone shape, and the diameter of the swirl tube 300 increases in the axial direction. Through this setting, cyclone tube 300 diameter crescent from top to bottom because first spinning disk 330 and second spinning disk 340 are the dextrorotation, have guaranteed that the air current through cyclone tube 300 revolves to the trend of rightwards and downstream, do benefit to the air current whirl.

In other embodiments, the swirl tube 300 may be a straight tube with a hollow center.

As shown in fig. 2 and fig. 5, the aftertreatment mixer further includes an air inlet baffle 500, the air inlet baffle 500 has a plurality of air inlets 501, and the air inlet baffle 500 is accommodated in the air inlet cavity 102 and covers the cyclone tube 300.

Through this setting, can make the air current evenly flow to cyclone tube 300 under the water conservancy diversion effect of baffle 500 that admits air, overcome the influence that the whirl trend that the increase spinning disk open area brought weakens simultaneously.

Specifically, in the embodiment shown in fig. 5, the air intake holes 501 include a first air intake hole 502 and a second air intake hole 503, which have different axial positions, the first air intake hole 502 is disposed corresponding to the first swirl hole 310, and the second air intake hole 503 is disposed corresponding to the second swirl hole 320.

In this embodiment, the axial size of the first intake holes 502 is smaller than that of the first swirl holes 310, and the axial size of the second intake holes 503 is smaller than that of the second swirl holes 320. Through this setting, overcome the influence that the whirl trend that increases spinning disk open area brought weakens.

In the present embodiment, the axial size of the first swirl holes 310 is greater than the axial size of the second swirl holes 320, and accordingly, the axial size of the first intake holes 502 is greater than the axial size of the second intake holes 503. The first and second swirl holes 310 and 320 are elongated, and correspondingly, the first and second intake holes 502 and 503 are also elongated.

In the present embodiment, the number of the first intake holes 502 and the number of the second intake holes 503 are both multiple, the multiple first intake holes 502 are arranged at intervals along the peripheral side of the intake baffle 500, and the size, shape and axial position of the multiple first intake holes 502 are the same. A plurality of second inlet ports 503 are along the week side interval distribution of cyclone tube 300, and a plurality of second inlet ports 503's size shape and axial position are all the same, do benefit to the homogeneity of guaranteeing the air current whirl. In other embodiments, the size and the axial position of the first intake holes 502 may be staggered, and the size and the axial position of the second intake holes 503 may be staggered.

As shown in fig. 5, the intake baffle 500 has a semi-cylindrical shape. Through this setting, outside air current major part can be in the vortex pipe 300 of evenly flowing in under the water conservancy diversion effect of baffle 500 that admits air, and remaining part air current can be walked around the baffle 500 rear that admits air in the chamber 102 that admits air of baffle 500 inflow, in the rear whirl import whirl by vortex pipe 300 to vortex pipe 300 again, does benefit to the air current evenly distributed in the chamber 102 that admits air.

In this embodiment, the top side of the air inlet baffle 500 is welded to the cyclone tube 300, and the bottom side of the air inlet baffle 500 is welded to the partition 200. In other embodiments, the top side of the inlet baffle 500 can be removably attached to the swirl tube 300 and the bottom side of the inlet baffle 500 can be removably attached to the baffle 200.

As shown in fig. 1 and fig. 5, the aftertreatment mixer further includes an outlet baffle 600, the outlet baffle 600 has a plurality of outlet holes 601, and the outlet baffle 600 is connected to the housing 100 and partially covers the opening of the outlet cavity 103.

In one embodiment, as shown in fig. 1, the opening of the outlet cavity 103 is circular, and the outlet baffle 600 is semicircular. Through this setting, promote the air current distribution homogeneity of giving vent to anger chamber 103, compare in ordinary circular baffle 600 of giving vent to anger, further reduce the backpressure value of aftertreatment blender.

In other embodiments, the air outlet baffle 600 may have a wavy or irregular shape.

As shown in fig. 5, the aftertreatment mixer further includes a cap 700, the cap 700 having a plurality of vents (not shown), the cap 700 being disposed at an end of the outer tube 420 remote from the inner tube 410. Through this setting, do benefit to the even outflow of air current in outer pipe 420, play the water conservancy diversion effect.

In a specific embodiment, the blanking cap 700 is welded to the inner wall of the outer tube 420. In other embodiments, the plug cover 700 can be inserted or clamped into the inner wall of the outer tube 420 for easy assembly and disassembly and recycling.

As shown in fig. 4 and 5, the aftertreatment mixer further includes a spoiler 800, the spoiler 800 has a plurality of pressure reducing holes 801, and the spoiler 800 is obliquely disposed outside the cap 700.

By the arrangement, because the spoiler 800 is inclined, the spoiler 800 does not completely seal the bottom of the outer layer pipe 420, and the exhaust gas flow flowing out of the lower port of the outer layer pipe 420 can be buffered and guided; meanwhile, the smoothness of the exhaust gas flow is ensured by the arrangement of the pressure reduction holes 801.

In a specific embodiment, the spoiler 800 has a W shape, and the spoiler 800 is welded to the bottom side of the outer pipe 420 in an inclined manner and is positioned outside the cap 700. In other embodiments, the spoiler 800 may have other irregular shapes.

In one embodiment, to reinforce the spoiler 800, the housing 100 is provided with a locking groove (not shown), and the spoiler 800 is provided with a protrusion 802, wherein the protrusion 802 can be locked in the locking groove.

In the embodiment shown in fig. 4, the aftertreatment mixer further includes a mounting block 900 and a nozzle, the mounting block 900 is disposed on the top side of the casing 100, and the nozzle is mounted on the mounting block 900 and used for spraying the solution into the inner pipe 410.

Specifically, the solution is a urea solution.

In this embodiment, as shown in fig. 7, the inner tube 410 includes a first cyclone section 411, a transition section 412 and a second cyclone section 413 connected to each other, the solution is injected into the first cyclone section 411, the first cyclone section 411 and the second cyclone section 413 are provided with a plurality of cyclone holes 414, and the transition section 412 is smooth and is not provided with the cyclone holes 414.

Through this setting, avoid the air current to directly blow the urea solution, show the risk that reduces the urea solution crystallization in the hybrid tube 400, improve the utilization ratio of urea solution.

In a specific embodiment, as shown in fig. 7, a first flange 415 is provided on the top side of the inner tube 410, a second flange 416 is provided on the bottom side of the inner tube 410, a third flange (not shown) is provided on the bottom side of the cyclone tube 300, the first flange 415 is connected to the third flange, and the second flange 416 is connected to the inner wall of the outer tube 420, so as to fix the inner tube 410.

In the embodiment shown in fig. 4, the diameter of the outer tube 420 is larger than the diameter of the inner tube 410, and the outer tube is provided with a plurality of first holes 421. With this arrangement, after the air flow enters the outer tube 420 through the inner tube 410, the air flow area is increased, and the back pressure of the aftertreatment mixer is reduced.

As shown in fig. 1 and 5, the housing 100 includes an inner housing 110, an outer housing 120, and an end cap 130, the end cap 130 is integrally connected to the inner housing 110, and the outer housing 120 and the end cap 130 are connected by a reinforcing plate 140.

In the present embodiment, the end cap 130 is welded to the inner case 110, the outer case 120 is welded to the end cap 130 via the reinforcing plate 140, and a ceramic fiber mat is filled between the inner case 110 and the outer case 120. Through this arrangement, the reinforcing plate 140 plays a role of fixing and reinforcing, and simultaneously can seal the ceramic fiber mat filled between the inner and outer shells 120, thereby preventing the ceramic fiber mat from being exposed.

In the present embodiment, the partition plate 200 is fixed in the inner case 110 by welding, and has high mechanical strength and good stability. In other embodiments, partition 200 may be detachably connected to inner housing 110 by snapping, plugging, etc.

In the above post-treatment mixer, as shown in fig. 4 and 5, the specific flow paths of the gas flow are as follows:

tail gas discharged by the engine flows to the air inlet cavity 102, wherein part of the air flow Q is guided by the air inlet baffle 500 and flows to the front of the cyclone tube 300, and the rest of the air flow S bypasses the air inlet baffle 500 and flows to the rear of the cyclone tube 300 in the air inlet cavity 102;

in the partial airflow Q flowing to the front of the cyclone tube 300, the airflow Q will swirl into the cyclone tube 300 from the first cyclone inlet 301 and the second cyclone inlet 302 in the front, wherein a part of the airflow Q1 will flow into the inner tube 410 from the cyclone tube 300, and another part of the airflow Q2 will not flow into the inner tube 410 but between the inner wall of the cyclone tube 300 and the outer wall of the inner tube 410; the air flow between the inner wall of the cyclone tube 300 and the outer wall of the inner tube 410 can continuously heat the inner tube 410, so that the risk of urea crystallization is obviously reduced, and the utilization rate of urea solution is improved;

the remaining part of the airflow S flowing to the rear of the cyclone tube 300 is swirled into the cyclone tube 300 through the first and

second swirl inlets

301 and 302 at the rear, and flows into the inner tube 410 through the cyclone tube 300;

the urea solution is sprayed into the inner pipe 410 through the nozzle, and under the action of the rotational flow, the air flow in the inner pipe 410 is mixed with the urea solution and collides with the inner wall of the inner pipe 410, so that the air flow is fully mixed with the urea solution and then flows to the outer pipe 420, and finally flows into the blocking cover 700 and the spoiler 800 and is discharged from the air outlet cavity 103.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. An aftertreatment mixer, comprising:

a housing having an interior cavity;

the mixed pipe comprises an inner layer pipe and an outer layer pipe, the outer layer pipe is contained in the air outlet cavity and connected with the cyclone pipe, and the inner layer pipe is contained in the cyclone pipe and connected with the outer layer pipe;

the air inlet baffle is accommodated in the air inlet cavity and covers the cyclone tube, and the air inlet baffle is provided with a plurality of air inlets;

when the air flow flows from the air inlet cavity to the cyclone tube, the air inflow of the first cyclone inlet is larger than that of the second cyclone inlet, the air flow is uniformly swirled by the cyclone tube and flows into the inner tube to be mixed with urea solution, and the mixed air flow is discharged through the outer tube and the air outlet cavity.

2. The aftertreatment mixer of claim 1, wherein the swirl tube has a first swirl hole and a second swirl hole with different axial positions on the circumferential side, wherein a first swirl plate is disposed on one side of the first swirl hole, the first swirl hole and the first swirl hole define the first swirl inlet, and a second swirl hole define the second swirl inlet.

3. The aftertreatment mixer of claim 2, wherein the first swirl plate extends obliquely outward from a side edge of the first swirl hole, wherein the second swirl plate extends obliquely outward from a side edge of the second swirl hole, and wherein the first swirl plate and the second swirl plate are inclined in the same direction.

4. The aftertreatment mixer of claim 2, wherein an axial dimension of the first swirl hole is greater than an axial dimension of the second swirl hole, and a radial dimension of the first swirl hole is equal to a radial dimension of the second swirl hole.

5. The aftertreatment mixer of claim 2, wherein the first swirler has an axial dimension that is less than an axial dimension of the first swirler hole and the second swirler has an axial dimension that is less than an axial dimension of the second swirler hole.

6. The aftertreatment mixer of claim 2, wherein the inlet baffle is semi-cylindrical and the axial dimension of the inlet holes is smaller than the axial dimensions of the first swirl hole and the second swirl hole.

7. The aftertreatment mixer of claim 1, further comprising an exhaust baffle having a plurality of exhaust holes, the exhaust baffle being coupled to the housing and partially shielded from the exhaust cavity opening.

8. The aftertreatment mixer of claim 7, wherein the outlet cavity opening is circular and the outlet baffle is semicircular.

9. The aftertreatment mixer of claim 1, further comprising a cap having a plurality of vent holes and a spoiler having a plurality of pressure reducing holes, the cap being disposed at an end of the outer tube remote from the inner tube, the spoiler being disposed obliquely outward of the cap.

10. The aftertreatment mixer of claim 9, wherein the spoiler is W-shaped, the housing defines a slot, and the spoiler defines a protrusion for engaging the slot.

11. The aftertreatment mixer of claim 1, further comprising a mounting block disposed on a top side of the housing and a nozzle mounted to the mounting block for spraying a solution into the inner pipe.

12. The aftertreatment mixer of claim 11, wherein the inner pipe comprises a first cyclone section, a transition section and a second cyclone section which are connected, the solution is sprayed on the first cyclone section, the first cyclone section and the second cyclone section are provided with a plurality of cyclone holes, and the transition section is smooth and is not provided with the cyclone holes.

13. The aftertreatment mixer of claim 1, further comprising at least one of:

14. An engine comprising an aftertreatment mixer according to any one of claims 1 to 13.