CN106224132B - A kind of EGR mixing arrangement - Google Patents

Abstract

The invention relates to the field of mixing devices, and discloses an EGR mixing device, which includes an EGR mixer, an EGR pipe and an intake pipe. The EGR mixer includes an annular hollow shell, and the outer wall of the hollow shell is provided with an inlet. , the inner wall of the hollow shell is circumferentially distributed with a plurality of outlets, and the cavity of the hollow shell forms an air flow channel; the air intake pipe includes a first air intake pipe and a second air intake pipe, and the first air intake pipe and The second air intake pipe is respectively connected to both ends of the hollow shell, the EGR mixer communicates with the first air intake pipe and the second air intake pipe through the plurality of outlets, and the inner diameter of the hollow shell is the same as the inner diameter of the hollow shell. The inner diameters of the first intake pipe and the second intake pipe are matched, and the EGR pipe is connected with the inlet of the hollow casing. The invention can not only improve the mixing uniformity of EGR, but also ensure low intake resistance.

Description

A kind of EGR mixing device

technical field

The invention relates to the technical field of mixing devices, in particular to an EGR mixing device.

Background technique

With the upgrading of emission regulations, EGR (Exhaust Gas Recirculation) technology is widely used in diesel engines as an effective means to control NO _x emissions. Part of the exhaust gas is introduced from the exhaust pipe into the intake pipe through an EGR pipeline, but after the exhaust gas is directly introduced into the intake pipe, it often cannot be effectively mixed with the fresh air (especially for models with a short mixing distance), resulting in different amounts of exhaust gas entering each cylinder. The same, which in turn leads to combustion deterioration, increased emissions and other consequences, affecting the performance of the whole machine.

In order to improve the mixing of EGR exhaust gas and fresh air and improve the EGR distribution uniformity of each cylinder, various EGR mixing devices have been designed. At the same time, the intake resistance will increase, and the pressure loss will be high; however, after the pressure loss is reduced, the EGR mixing uniformity will become worse, and it is difficult to find a balance between pressure loss and EGR mixing uniformity.

Contents of the invention

(1) Technical problems to be solved

The technical problem to be solved by the present invention is how to provide an EGR mixing device which can improve the EGR mixing uniformity and ensure low intake resistance.

(2) Technical solutions

In order to solve the above technical problems, the present invention provides an EGR mixing device, which includes an EGR mixer, an EGR pipe and an intake pipe, the EGR mixer includes an annular hollow shell, and the outer wall of the hollow shell is provided with an inlet , the inner wall of the hollow shell is circumferentially distributed with a plurality of outlets, and the cavity of the hollow shell forms an air flow passage; the air intake pipe includes a first air intake pipe and a second air intake pipe, and the first air intake pipe and The second intake pipe is respectively connected to both ends of the hollow casing, the EGR mixer communicates with the first intake pipe and the second intake pipe through the plurality of outlets, and the inner diameter of the hollow casing is the same as the inner diameter of the hollow casing. The inner diameters of the first intake pipe and the second intake pipe are matched, and the EGR pipe is connected with the inlet of the hollow casing.

Wherein, the plurality of outlets are arranged symmetrically with respect to the central axis of the inlet; the inner wall of the hollow shell near the inlet is provided with a pair of first outlets arranged symmetrically about the central axis; away from the inlet The inner wall of the hollow casing on the side is not provided with an outlet; the inner wall of the hollow casing is also provided with at least one pair of second outlets arranged symmetrically with respect to the central axis.

Wherein, both the first outlet and the second outlet are openings or through holes arranged along the axial direction of the hollow casing.

Wherein, the opening width of the first outlet is smaller than the opening width of the second outlet, and the length of the first outlet is consistent with the length of the second outlet.

Wherein, the EGR mixer further includes an elbow, the elbow is bent at a right angle; one end of the elbow is connected to the inlet, and the other end of the elbow is connected to the EGR pipe.

Wherein, the outer end of the first air intake pipe is connected to the air filter; the outer end of the second air intake pipe is used to connect to the cylinder of the engine.

Wherein, the axial ends of the hollow shell are respectively provided with flanges, and the first air intake pipe and the second air intake pipe are respectively connected to the hollow shell through corresponding flanges.

(3) Beneficial effects

Compared with the prior art, the present invention has the following advantages:

An EGR mixing device provided by the present invention includes an EGR mixer, an EGR pipe and an intake pipe, the EGR mixer includes an annular hollow shell, the outer wall of the hollow shell is provided with an inlet, and the hollow shell The inner wall of the body is distributed with a plurality of outlets in the circumferential direction, so that the gas flows in from the circumferential direction of the inner wall to ensure that the gas is mixed evenly; the inlet pipe includes a first inlet pipe and a second inlet pipe, and the first inlet pipe and the second inlet pipe The intake pipes are respectively connected to both ends of the hollow shell, the EGR mixer communicates with the first intake pipe and the second intake pipe through the multiple outlets, and the inner diameter of the hollow shell is the same as that of the first intake pipe. The inner diameters of the first intake pipe and the second intake pipe are matched to ensure that there is no structure at the EGR mixer to block the gas flow in the intake pipe, so the pressure loss at this position is very small and does not affect the intake air. The EGR pipe and The inlet of the hollow shell is connected to supply EGR to the EGR mixer. Therefore, the present invention achieves high mixing uniformity while ensuring low pressure loss.

Description of drawings

Fig. 1 is the front view of a kind of EGR mixing device of the present invention;

Fig. 2 is the three-dimensional schematic diagram of the EGR mixer in a kind of EGR mixing device of the present invention;

Fig. 3 is the axial sectional view of Fig. 2;

In the figure: 1: first intake pipe; 2: second intake pipe; 3: hollow shell; 4: EGR pipe; 5: bent pipe; 6: inlet; 7: first outlet; 8: second outlet; 9 : diversion wall.

Detailed ways

The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", " The orientations or positional relationships indicated by "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying Describes, but does not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and operate in a specific orientation, and therefore should not be construed as limiting the invention. In addition, the terms "first", "second", "third", etc. are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary, and it may be the internal communication of two components. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

In addition, in the description of the present invention, unless otherwise specified, the meanings of "plurality", "multiple roots" and "multiple groups" are two or more.

As shown in Figure 1, an EGR mixing device provided by the present invention includes an EGR mixer, an EGR pipe 4 and an intake pipe, and as shown in Figures 2-3, the EGR mixer includes an annular hollow shell 3. The outer wall of the hollow shell 3 is provided with an inlet 6, and the inner wall of the hollow shell 3 is distributed with a plurality of outlets in the circumferential direction, so that the gas flows into the intake pipe from the circumferential direction of the inner wall to ensure that the gas is mixed evenly. The cavity of the hollow housing 3 constitutes an airflow passage; the air intake pipe comprises a first air intake pipe 1 and a second air intake pipe 2, and the first air intake pipe 1 and the second air intake pipe 2 are connected to the hollow housing 3 respectively. The EGR mixer communicates with the first intake pipe 1 and the second intake pipe 2 through the plurality of outlets, and the inner diameter of the hollow shell 3 is connected with the first intake pipe 1 and the second intake pipe 1. The inner diameter of the intake pipe 2 is matched to ensure that there is no structure at the EGR mixer to block the gas flow in the intake pipe, so the pressure loss at this position is very small and does not affect the intake air. The EGR pipe 4 and the hollow shell The inlet 6 of the body 3 is connected to supply EGR to the EGR mixer. Therefore, the present invention obtains high mixing uniformity while ensuring low pressure loss of the EGR mixer.

Specifically, the plurality of outlets are arranged symmetrically with respect to the central axis of the inlet 6; further, on the inner wall of the hollow casing 3 near the inlet 6 (shown as directly below the inlet 6 in FIG. ) is provided with a pair of first outlets 7 symmetrically arranged with respect to the central axis, so that an inner wall without an outlet is left between the two first outlets 7 as a guide wall 9, so that EGR Under the action, it can flow into the airflow channel on both sides, and the first outlet 7 is set on both sides of the diversion wall 9 to allow a small part of the gas to pass through, so as to prevent the diversion effect of the diversion wall 9 from being too strong and resulting in too little EGR in the upper part of the intake pipe The inner wall of the hollow casing 3 far away from the inlet 6 side (shown in Fig. 3 as being far away from the directly below the inlet 6 side) is not provided with an outlet, so as to avoid that the gas only flows out from the lower outlet under the action of flow inertia. The mixing effect is poor; the inner wall of the hollow shell 3 is also provided with at least one pair of second outlets 8 arranged symmetrically with respect to the central axis, and the second outlets 8 are located on both sides of the first outlet 7 for splitting Air flow, as shown in Figure 3, is provided with two pairs of second outlets 8, of course, the more the outlets are set, the more uniform the gas mixing, but the more the outlets are set, the worse the manufacturing process of the EGR mixer is, therefore, it can be selected according to needs Appropriate quantity of exports.

Wherein, both the first outlet 7 and the second outlet 8 are openings or through holes arranged along the axial direction of the hollow casing 3 . Specifically, the opening width of the first outlet 7 is smaller than the opening width of the second outlet 8, and the length of the first outlet 7 is consistent with the length of the second outlet 8, so that the first outlet 7 is smaller than The second outlet 8 is provided with the first outlet 7 on the inner wall facing the incoming flow direction, so as to prevent the inner wall from being too strong, causing the flow rate of the second outlet 8 to be too small, and also to prevent the upper part of the intake pipe from having too little EGR.

As shown in Figure 2, the EGR mixer also includes a section of elbow 5, which is bent at a right angle; one end of the elbow 5 is connected to the inlet 6, and the other end of the elbow 5 is connected to the inlet 6. The EGR pipe 4 is connected so that the EGR pipe 4 is arranged horizontally after being connected with the EGR mixer, so as to facilitate air intake.

Wherein, the first air intake pipe 1 is used to feed fresh air, and its outer end is connected to an air filter to filter impurities in the air; the outer end of the second air intake pipe 2 is used to connect to the cylinder of the engine to The gas mixed with fresh air and EGR is sent to the cylinder.

In order to facilitate the connection of the intake pipe, the axial ends of the hollow shell 3 are respectively provided with flanges, and the first air intake pipe 1 and the second air intake pipe 2 are respectively connected to the hollow shell 3 through corresponding flanges. connected to form a cavity surrounding the intake pipe.

It can be seen from the above embodiments that the present invention can not only improve EGR mixing uniformity, but also ensure low intake resistance.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (6)

1. a kind of EGR mixing arrangement, including EGR mixer, EGR pipe and air inlet pipe, which is characterized in that the EGR mixer packet Include hollow shell annular in shape, the outer wall of the hollow shell is equipped with entrance, the inner wall of the hollow shell is circumferentially distributed have it is more The cavity of a outlet, the hollow shell constitutes airflow channel；The air inlet pipe includes the first air inlet pipe and the second air inlet pipe, institute It states the first air inlet pipe and the second air inlet pipe is connected to the both ends of the hollow shell, the EGR mixer passes through described more A outlet is connected to first air inlet pipe, the second air inlet pipe, the internal diameter of the hollow shell and first air inlet pipe, second The internal diameter of air inlet pipe matches, and the EGR pipe is connected with the entrance of the hollow shell；The multiple outlet is about the entrance Central axis be symmetrical arranged；It is equipped with close to the inner wall of the hollow shell of the entrance side symmetrical about the central axis A pair of of first outlet of setting；The inner wall of the hollow shell far from the entrance side is not provided with outlet；Positioned at described hollow The inner wall of shell is additionally provided at least a pair about the symmetrically arranged second outlet of the central axis.

2. EGR mixing arrangement according to claim 1, which is characterized in that the first outlet and second outlet are edge The opening being axially arranged or through-hole of the hollow shell.

3. EGR mixing arrangement according to claim 1, which is characterized in that the opening width of the first outlet is less than institute The opening width of second outlet is stated, the length of the first outlet is consistent with the length of the second outlet.

4. EGR mixing arrangement according to claim 1, which is characterized in that the EGR mixer further includes one section of bend pipe, The elbow curvature is rectangular；One end of the bend pipe is connect with the entrance, and the other end of the bend pipe and the EGR pipe connect It connects.

5. EGR mixing arrangement according to claim 1, which is characterized in that the outer end of first air inlet pipe connects air Filter；The outer end of second air inlet pipe is used to connect the cylinder of engine.

6. EGR mixing arrangement according to claim 1, which is characterized in that the axial ends of the hollow shell is set respectively There is flange, first air inlet pipe and the second air inlet pipe pass through corresponding flange respectively and connect with the hollow shell.