CN112628033B

CN112628033B - Condensed water separation component, mixer with same and EGR system

Info

Publication number: CN112628033B
Application number: CN201910906979.1A
Authority: CN
Inventors: 闫岩; 王乾; 于冠军; 李世伟; 王玉军; 尹琪
Original assignee: SAIC Motor Corp Ltd
Current assignee: SAIC Motor Corp Ltd
Priority date: 2019-09-24
Filing date: 2019-09-24
Publication date: 2022-04-22
Anticipated expiration: 2039-09-24
Also published as: CN112628033A

Abstract

The invention discloses a condensed water separation component, a mixer with the same and an EGR system, and the condensed water separation component for the mixer of the EGR system comprises a separation cylinder body which can be embedded in an internal flow passage of the mixer, and the separation cylinder body is configured as follows: a preset radial interval is arranged between the outer peripheral surface of the inner flow passage and the inner wall of the inner flow passage to form an exhaust gas flow passage; the separating cylinder body is provided with a plurality of radially through air inlets, and two axial ends of the separating cylinder body can be fixedly connected with two ends of the internal flow passage in a sealing manner. According to the invention, the condensed water separation part is utilized through structural optimization, so that condensed water separation can be effectively realized, the possibility that the condensed water impacts and corrodes the high-speed rotating impeller of the supercharger is avoided, and technical guarantee is provided for ensuring the service life of the impeller.

Description

Condensed water separation component, mixer with same and EGR system

Technical Field

The invention relates to the technical field of automobile EGR (exhaust gas recirculation) systems, in particular to a condensed water separation component, a mixer with the same and an EGR system.

Background

Referring to fig. 1, a schematic of the overall configuration of a typical EGR (Exhaust Gas Recirculation) system mixer is shown. The mixer is integrally provided with a crankcase ventilation duct connection 10, an exhaust gas recirculation connection 20, a fresh air intake connection 30, and a booster compressor connection 40. By designing the shape of the flow passage and the distance between each air inlet and the supercharger, the EGR gas and the fresh air can be uniform before compression.

It is well known that the EGR gas component has a relatively high water content, and particularly when the EGR gas is operated under a small load or a frequent start-stop condition in an engine, a part of condensed water may be separated out from the EGR gas before the EGR gas enters the exhaust gas recirculation joint 20; the condensed water is brought into the supercharger, and the impeller under the high-speed rotation of the supercharger is impacted and corroded by the condensed water, so that the impeller is aged and failed.

In addition, oil and gas in the crankcase ventilation gas entering through the crankcase ventilation pipe joint 10 under high load may be emulsified with condensed water generated therein, resulting in pipeline blockage.

In order to solve the problem caused by the condensate water precipitation, the prior art provides corresponding measures, mainly by coating the supercharger blades or closing the EGR system under a specific environment or a condensation risk working condition. However, neither of these solutions fundamentally solves the problem, and applying a coating to the supercharger only increases the service life of the supercharger blades against impact, but if the frequency of condensation is high, the coating does not guarantee that the blades will not be damaged during the life cycle required by the supercharger. In addition, the engine gains in emissions and fuel consumption are affected by shutting down the EGR system under certain operating conditions.

In view of the above, it is desirable to optimize the existing supercharger to effectively control the adverse effect of the condensed water.

Disclosure of Invention

In order to solve the technical problems, the invention provides a condensate water separation component, a mixer with the condensate water separation component and an EGR system.

The invention provides a condensate water separation component for an EGR system mixer, which comprises a separation cylinder body which can be embedded in an internal flow passage of the mixer, and the separation cylinder body is configured as follows: a preset radial interval is arranged between the outer peripheral surface of the inner flow passage and the inner wall of the inner flow passage to form an exhaust gas flow passage; the separating cylinder body is provided with a plurality of radially through air inlets, and two axial ends of the separating cylinder body can be fixedly connected with two ends of the internal flow passage in a sealing manner.

Preferably, a plurality of the intake holes are provided on a side wall of the separation cylinder body which is not diametrically opposite to the exhaust gas inflow joint of the mixer.

Preferably, a plurality of the inlet port sets up to the multiunit that axial interval set up, and a plurality of every group the inlet port circumference is equidistant equipartition.

Preferably, a baffle plate is arranged corresponding to each air inlet hole, extends from the separating cylinder body to the waste gas flow channel and is positioned at the hole edge position on the opposite side of the waste gas flow direction of the air inlet hole.

Preferably, the baffle and the separating cylinder body can be integrally formed or fixedly connected in a split mode.

The invention also provides a mixer, which comprises a mixer body with an internal flow passage, wherein two axial ports of the internal flow passage are respectively a fresh air joint and a supercharger compressor joint, and the radial side wall of the mixer body is provided with a waste gas inflow joint and a crankcase ventilation pipe joint which are communicated with the internal flow passage; also included is a condensate separation component as previously described.

Preferably, the axial two ends of the separating cylinder body are respectively provided with bending sections extending outwards in the radial direction, wherein the outer edge of the first bending section is in sealing connection with the end part of the internal flow channel on the corresponding side of the fresh air connector, and the outer edge of the second bending section is in sealing connection with the end part of the internal flow channel on the corresponding side of the supercharger compressor connector.

Preferably, the end part of the inner flow channel on the side corresponding to the fresh air connector is provided with an inner concave part, the first bending section is fixed on the inner concave part in an overlapping manner, and the outer end face of the first bending section is flush with the end face of the mixer body.

Preferably, a crankcase ventilation pipe joint is inserted into the inner cavity of the separation cylinder body.

The invention also provides an EGR system with the mixer.

The invention provides a condensed water separation component applicable to an internal flow passage of a mixer in a new way, a plurality of radial through air inlets are arranged on a separation cylinder body, and a preset radial interval is arranged between the outer peripheral surface of the separation cylinder body and the inner wall of the internal flow passage to form a waste gas flow passage; and the two axial ends of the separation cylinder body can be fixedly connected with the two ends of the internal flow passage in a sealing way. According to the arrangement, the waste gas enters the waste gas flow channel to flow around the separation cylinder body, condensed liquid drops contained in the waste gas flow can be separated out under the action of flowing centrifugal force and are attached to the inner wall of the mixer, and the waste gas after liquid drop separation enters the flow channel in the separation cylinder body through each air inlet; therefore, the condensed water can be effectively separated, the possibility that the condensed water impacts and corrodes the impeller rotated at high speed by the supercharger is avoided, and the technical guarantee is provided for ensuring the service life of the impeller.

In a preferred embodiment of the present invention, the plurality of inlet openings are provided in a side wall of the separator body that is not diametrically opposite the exhaust gas inflow connection, i.e., no inlet opening is provided in a region of the separator body that is opposite the exhaust gas inflow connection. On one hand, liquid drops of the waste gas flow entering the mixer in the radial direction collide with the side wall of the separation cylinder body which is not provided with the air inlet and are attached to the side wall; in addition, the side wall of the radial direction and the non-radial direction opposite to the waste gas inflow joint is not provided with an air inlet, so that good winding guide can be formed, the centrifugal force of flow drop separation is improved, and the separation effect of condensed water is further improved.

In another preferred embodiment of the present invention, a baffle is disposed corresponding to each air inlet, and extends from the separator body into the exhaust gas flow passage, so as to further increase the collision contact area of the exhaust gas flow, and further improve the ability of the separator to capture condensed water.

Drawings

FIG. 1 is a schematic diagram of a typical EGR system mixer of the prior art;

FIG. 2 is a schematic diagram showing the overall structure of the mixer according to the embodiment;

FIG. 3 is a front view of a mixer according to an embodiment;

FIG. 4 is a cross-sectional view A-A of FIG. 3;

FIG. 5 is a top view of an embodiment of the mixer;

FIG. 6 is a cross-sectional view B-B of FIG. 5;

FIG. 7 shows the assembled relationship of the crankcase ventilation tube connector and the separator cylinder body.

In the figure:

the separating cylinder comprises a separating cylinder body 1, an air inlet 11, a baffle 12, a first bending section 13 and a second bending section 14;

mixer body 2, exhaust gas inflow joint 21, crankcase ventilation pipe joint 22, fresh air joint 23, supercharger compressor joint 24, internal flow passage 25, exhaust gas flow passage 251, and concave portion 26.

Detailed Description

In order to make the technical solutions of the present invention better understood by those skilled in the art, the present invention will be further described in detail with reference to the accompanying drawings and specific embodiments.

Without loss of generality, the embodiment takes the mixer body of an EGR (Exhaust Gas Recirculation) system as a description basis, and describes the technical scheme of the matched condensed water separation component in detail. It should be understood that the relationship between the positions of the ports of the mixer body and the dimensional ratios of the internal flow passages are not essential limitations to the claimed solution.

Referring to fig. 2 and 3, fig. 2 is a schematic structural diagram of a mixer of an EGR system according to the present embodiment, and fig. 3 is a front view of the mixer.

As shown in the figure, the EGR mixer includes a mixer body 2, an exhaust gas inflow joint 21 and a crankcase ventilation pipe joint 22 communicating with an internal flow passage 25 are opened on a radial side wall of the mixer body 2, and a fresh air joint 23 and a supercharger compressor joint 24 are respectively provided at two axial ports of the internal flow passage 25. As in the prior art, the mixer is used to form exhaust gas which enters the internal flow passage 25 and is uniformly mixed with fresh air, so that part of the exhaust gas is introduced and combusted again, and the content of nitrogen oxides (NOx) in the exhaust gas is reduced.

The mixer further comprises a condensed water separation component, and particularly, a separation cylinder body 1 is embedded and arranged in the inner flow passage 25 of the mixer body 2. Please also refer to fig. 4, which is a sectional view a-a of fig. 3.

As shown in fig. 4, the separation cylinder body 1 is a rotary body. The outer peripheral surface of which is spaced from the inner wall of the inner flow passage 25 by a predetermined radial distance D to form an exhaust gas flow passage 251, which is substantially annular. Furthermore, the separating cylinder body 1 is provided with a plurality of radially through air inlets 11, and two axial ends of the separating cylinder body are fixedly connected with two ends of the internal flow passage 25. In practical application, the waste gas enters the waste gas flow channel 251 to flow around the separation cylinder body 1, condensed liquid drops contained in the waste gas flow can be separated out under the action of a flowing centrifugal force and are attached to the inner wall of the mixer body 2, and the waste gas after liquid drop separation enters the flow channel in the separation cylinder body 1 through each air inlet 11, so that condensed water separation can be effectively realized.

Specifically, the number of the air intake holes 11 can be set according to the specific system processing needs. For example, but not limited to the preferred scheme shown in the figures, the plurality of air inlet holes 11 are arranged into three groups which are axially arranged at intervals, and the plurality of air inlet holes 11 in each group are uniformly distributed at equal intervals in the circumferential direction; that is, the plurality of air inlet holes 11 may be axially spaced in other plural sets.

The terms "axial," "circumferential," "radial," and "inner," "outer," etc., as used herein, are defined with reference to the internal flow passage. It is to be understood that the above directional terms are used merely for clear representation of the relative positions of the components and structures, and do not limit the technical solutions claimed in the present application.

In order to further enhance the separation effect of the condensed water, it is preferable that a plurality of air intake holes 11 are provided on a side wall of the separation cylinder body 1 that is not diametrically opposed to the exhaust gas inflow joint 21 of the mixer. That is, the portion of the separation cylinder body 1 opposite to the exhaust gas inflow joint 21 is not provided with the intake port 11. Thus, the liquid drops in the exhaust gas flow entering the mixer in the radial direction firstly collide with the side wall (bottom in the figure) of the separation cylinder body 1 without the air inlet 11 and are attached to the side wall to form the first-stage separation of condensed water; in addition, based on the design without the air inlet 11, the exhaust gas flow entering the exhaust gas flow channel 251 is guided by two paths, the centrifugal force of flow drop separation can be further improved by good winding, and the exhaust gas flow is attached to the inner wall of the mixer body 2 to form secondary separation of condensed water, so that the separation effect of the condensed water is further improved.

In addition, the air inlet holes 11 may be square holes, circular holes, or other irregularly shaped holes, as long as an exhaust gas flow path for performing droplet separation can be formed. Likewise, the shape of the air intake holes 11 is not limited to the square air intake holes 11 of the preferred example in the drawings.

In addition, a baffle plate 12 is provided corresponding to each intake hole 11, and is formed by extending from each baffle plate 12 into the exhaust gas flow channel 251 through the separation cylinder body 1; fig. 5 and fig. 6 are combined, wherein fig. 5 is a top view of the mixer, and fig. 6 is a cross-sectional view B-B of fig. 5.

Specifically, the baffle 12 is specifically located at the hole edge position on the opposite side of the exhaust gas swirling flow direction of the intake hole 11 to further increase the collision contact area of the exhaust gas flow, to form three-stage separation of condensed water, which can further improve the capability of the separation component to capture the condensed water.

It should be noted that the baffle 12 and the separation cylinder body 1 may be integrally formed, for example, but not limited to, integrally press-formed; or the baffle plate 12 is fixedly connected with the separation cylinder body 1 in a split manner, for example, but not limited to, fixed by adopting a welding process.

In order to improve the reliability of the sealing connection between the separation cylinder body 1 and the mixer body 2, as shown in fig. 4, it is preferable that the separation cylinder body 1 has bent sections extending radially outward at both axial ends, wherein the outer edge of the first bent section 13 is in sealing connection with the end of the internal flow passage 25 on the corresponding side of the fresh air connector 23, and the outer edge of the second bent section 14 is in sealing connection with the end of the internal flow passage 25 on the corresponding side of the supercharger compressor connector 24. By the arrangement, the sealing structure has better manufacturability on the basis of obtaining good sealing reliability.

Furthermore, the end of the internal flow channel 25 on the side corresponding to the fresh air connection 23 has an internal recess 26, wherein the first bend 13 is fixed in overlapping manner to the internal recess 26 in order to better adapt to the intake pressure; and after the sealing connection is finished, the outer end face of the first bending section 13 is flush with the end face of the mixer body 2, so that the assembly of the related components is facilitated.

Further, the crankcase ventilation pipe joint 22 is preferably inserted into the inner cavity of the separation cylinder body 1, as shown in fig. 7. So set up, gas in the crankcase ventilation pipe can not with condensate water droplet direct contact to oil gas and water mix production emulsion reaction in having avoided crankcase ventilation pipe gas, and then effectively avoid and lead to the pipeline to block up the problem from this.

Through production test, the scheme effectively avoids the adverse effect of the condensed water on the mixer through three-level condensed water separation.

According to the CAE simulation result, the condensed water separator can separate 99% of liquid drops larger than 10 microns in EGR gas. The liquid drops below 10 microns do not affect the service life of the supercharger blades, so that the service life of the supercharger blades can be effectively protected. Meanwhile, the design of circumferential surrounding air inlet is adopted, the uniformity of temperature and speed when the EGR gas and the fresh air are mixed is ensured, and the uniformity of temperature and speed can reach more than 0.9 through simulation calculation. The temperature and the flow on the side of the supercharger blade are effectively ensured to be uniformly distributed, and the service life of the supercharger blade is further ensured.

In addition to the aforementioned mixer, the present embodiment also provides an EGR system having the mixer, and it should be noted that other functions of the EGR system constitute non-core points of the invention of the present application, and those skilled in the art can implement the EGR system based on the prior art, and therefore, the details are not described herein again.

In particular, the preferred embodiment provided by the present embodiment is not limited to the preferred example shown in the drawings, and for example, the EGR mixer body 2 may be formed by dividing into two pieces, and then the separation cylinder body 1 may be fitted and fixed, and then the EGR mixer housing may be welded and formed. It should be understood that it is within the scope of the claims of the present application as long as the core inventive concept of the present application is applied to achieve an effective separation of condensed water.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that it is obvious to those skilled in the art that various modifications and improvements can be made without departing from the principle of the present invention, and these modifications and improvements should also be considered as the protection scope of the present invention.

Claims

1. A condensate separation component for an EGR system mixer, comprising:

a separation cartridge body that is nestable in the internal flow passage of the mixer, and that is configured to: a preset radial interval is arranged between the outer peripheral surface of the inner flow passage and the inner wall of the inner flow passage to form an exhaust gas flow passage; the separation cylinder body is provided with a plurality of radially through air inlets, and two axial ends of the separation cylinder body can be fixedly connected with two ends of the internal flow passage in a sealing manner; the plurality of air inlet holes are formed in the side wall of the separating cylinder body, which is not radially opposite to the waste gas inflow joint of the mixer;

the waste gas separation device is characterized by further comprising baffle plates which are arranged corresponding to the air inlet holes, extend from the separation cylinder body to the waste gas flow channel, and are located at the hole edge positions on the opposite sides of the waste gas flowing direction of the air inlet holes.

2. The condensate water separating unit according to claim 1, wherein the plurality of air inlet holes are arranged in a plurality of axially spaced groups, and the plurality of air inlet holes of each group are circumferentially and equally spaced.

3. The condensate separation device according to claim 1 or 2, wherein the baffle plate and the separation cylinder body are integrally formed or fixedly connected in a split manner.

4. A mixer comprises a mixer body with an internal flow passage, wherein two axial ports of the internal flow passage are respectively a fresh air joint and a supercharger compressor joint, and a radial side wall of the mixer body is provided with a waste gas inflow joint and a crankcase ventilation pipe joint which are communicated with the internal flow passage; characterized in that it further comprises a condensation water separation element according to any one of claims 1 to 3.

5. The mixer of claim 4 wherein the axial ends of the separator body each have a radially outwardly extending bend, wherein the outer edge of the first bend is in sealing engagement with the end of the internal flow path on the respective side of the fresh air connection and the outer edge of the second bend is in sealing engagement with the end of the internal flow path on the respective side of the booster compressor connection.

6. The mixer of claim 5 wherein the end of the internal flow passage on the side corresponding to the fresh air connection has an internal recess, the first bend section is fixed in overlapping relation to the internal recess, and the outer end face of the first bend section is flush with the end face of the mixer body.

7. The mixer of any one of claims 4-6, wherein a crankcase ventilation tube fitting is inserted into the internal cavity of the separator cartridge body.

8. An EGR system comprising a mixer, characterized in that the mixer is embodied as a mixer according to any of claims 4 to 7.