CN215860408U

CN215860408U - Mixing chamber subassembly and tail gas aftertreatment encapsulation

Info

Publication number: CN215860408U
Application number: CN202121918369.2U
Authority: CN
Inventors: 吴涛涛; 王长林; 李硕; 郑鑫
Original assignee: Tenneco Suzhou Emission System Co Ltd
Current assignee: Tenneco Suzhou Emission System Co Ltd
Priority date: 2021-08-16
Filing date: 2021-08-16
Publication date: 2022-02-18
Anticipated expiration: 2031-08-16

Abstract

A mixing chamber assembly includes a mixing chamber housing and a mixing tube assembly. The mixing chamber housing is provided with a first opening for communicating with a first aftertreatment carrier assembly and a second opening for communicating with a second aftertreatment carrier assembly. The mixing chamber assembly further comprises a rotational flow device, and the rotational flow device comprises a rotational flow cavity. Compared with the prior art, the cyclone device provided by the utility model has the advantages that the flow stroke of the airflow is increased, so that the uniformity of airflow mixing is improved. The utility model also relates to an exhaust aftertreatment package comprising the mixing chamber assembly.

Description

Mixing chamber subassembly and tail gas aftertreatment encapsulation

Technical Field

The utility model relates to a mixing cavity assembly and an exhaust aftertreatment package, and belongs to the technical field of engine exhaust aftertreatment.

Background

Studies have shown that the degree of uniformity of ammonia distribution in the lines of an exhaust aftertreatment system (e.g., a selective catalytic reduction system, SCR system) has a significant impact on the overall performance and durability of the system. The uneven distribution of ammonia over time can result in uneven catalyst aging, thereby affecting the overall performance of the catalyst. How to improve the uniformity of the distribution of the gas flow on the end surface of the carrier is a technical problem for those skilled in the art.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a mixing cavity assembly with good airflow distribution uniformity and tail gas aftertreatment packaging.

In order to achieve the purpose, the utility model adopts the following technical scheme: a mixing cavity assembly comprises a mixing cavity shell and a mixing tube assembly arranged in the mixing cavity shell, wherein the mixing cavity shell is provided with a first opening communicated with a first post-processing carrier assembly, a second opening communicated with a second post-processing carrier assembly, a first cavity communicated with the first opening and a second cavity communicated with the second opening; the mixing tube assembly comprises a swirl tube located in the first cavity and a connecting tube located in the second cavity; the cyclone tube is provided with a first inner cavity, a plurality of cyclone plates and an airflow inlet corresponding to the cyclone plates, the first inner cavity is communicated with the first cavity through the airflow inlet, the connecting tube is provided with a second inner cavity communicated with the first inner cavity, and the second inner cavity is communicated with the second cavity; the mixing cavity assembly further comprises a rotational flow device which is located in the second cavity and connected with the connecting pipe, the rotational flow device comprises a rotational flow cavity, and the connecting pipe is at least partially inserted into the rotational flow cavity.

As a further improved technical scheme of the utility model, the rotational flow device comprises a top wall, the top wall is provided with a mounting hole communicated with the rotational flow cavity, and the connecting pipe is partially inserted into the mounting hole.

As a further improved technical solution of the present invention, the top wall includes a first side and a second side opposite to the first side, and the swirling device includes a connecting wall extending downward from the second side and toward the first side.

As a further improved technical scheme of the utility model, the connecting wall is provided with an arc-shaped inner wall surface.

As a further improved technical solution of the present invention, the swirling device includes an airflow outlet between the connecting wall and the first side.

As a further improved technical scheme of the utility model, the mixing cavity assembly also comprises a perforated plate which is positioned on one side of the swirling device close to the second aftertreatment carrier assembly.

As a further improved technical scheme of the utility model, the porous plate is fixed on the mixing cavity assembly, and is suspended in the second cavity.

As a further improved technical scheme of the utility model, a plurality of airflow perforations are arranged on the pipe wall of the connecting pipe in the rotational flow cavity.

As a further improved technical solution of the present invention, the mixing tube assembly further includes an arc-shaped plate located in the first cavity and partially surrounding the cyclone plate, so that the tail gas can enter the cyclone tube from the airflow inlet only by bypassing the arc-shaped plate, and the cross section of the arc-shaped plate is C-shaped.

The utility model also discloses an exhaust aftertreatment package which comprises a first aftertreatment carrier component, a second aftertreatment carrier component, a third aftertreatment carrier component positioned at the upstream of the first aftertreatment carrier component and a mixing cavity component for connecting the first aftertreatment carrier component and the second aftertreatment carrier component, wherein the first aftertreatment carrier component is a diesel particle trap, the second aftertreatment carrier component is a selective catalytic reducing agent, the third aftertreatment carrier component is a diesel oxidation catalyst, and the mixing cavity component is the mixing cavity component.

Compared with the prior art, the cyclone device provided by the utility model has the advantages that the flow stroke of the airflow is increased, so that the uniformity of airflow mixing is improved.

Drawings

FIG. 1 is a schematic view of an exhaust aftertreatment package of the present invention.

FIG. 2 is a perspective view of a mixing chamber assembly of the present invention in one embodiment.

Fig. 3 is a front view of fig. 2.

Fig. 4 is an exploded perspective view of fig. 2.

Fig. 5 is a perspective view of the swirling device of fig. 4.

Fig. 6 is a front view of fig. 5.

Fig. 7 is a top view of fig. 5.

Fig. 8 is a left side view of fig. 5.

Detailed Description

The following detailed description of the embodiments of the utility model will be described in conjunction with the accompanying drawings, in which, if there are several embodiments, the features of these embodiments can be combined with each other without conflict. When the description refers to the accompanying drawings, like numbers or symbols in different drawings represent the same or similar elements unless otherwise specified. The statements made in the following exemplary embodiments do not represent all embodiments of the present invention, but rather they are merely examples of products consistent with the present invention as recited in the claims of the present invention.

The terminology used in the description of the utility model herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the present invention. It should be understood that the use of terms such as "first," "second," and the like, in the description and in the claims of the present invention do not denote any order, quantity, or importance, but rather the terms are used to distinguish one element from another.

Referring to fig. 1, the present invention discloses an exhaust gas aftertreatment package, which includes a first aftertreatment carrier assembly 1, a second aftertreatment carrier assembly 2, a third aftertreatment carrier assembly 3 located upstream of the first aftertreatment carrier assembly 1, and a mixing chamber assembly 4 connecting the first aftertreatment carrier assembly 1 and the second aftertreatment carrier assembly 2. In one embodiment of the utility model, the first aftertreatment carrier component 1 is a diesel particulate trap (DPF), the second aftertreatment carrier component 2 is a Selective Catalytic Reduction (SCR) and the third aftertreatment carrier component 3 is a Diesel Oxidation Catalyst (DOC).

The mixing chamber assembly 4 includes a mixing chamber housing 5 and a mixing tube assembly 6 mounted within the mixing chamber housing 5. The mixing chamber housing 5 is provided with a first opening 51 for communicating with a first aftertreatment carrier assembly 1, a second opening 52 for communicating with a second aftertreatment carrier assembly 2, a first cavity 53 communicating with the first opening 51, a second cavity 54 communicating with the second opening 52, and a partition 55 between the first cavity 53 and the second cavity 54.

The mixing tube assembly 6 includes a swirl tube 61 located in the first chamber 53, a connecting tube 62 located in the second chamber 54, and an arcuate plate 63 located within the first chamber 53 and partially surrounding the swirl tube 61.

The cyclone tube 61 is provided with a first inner cavity 611, a plurality of cyclones 612 and an air inlet 613 corresponding to the cyclones 612. The first inner cavity 611 communicates with the first cavity 53 through the gas flow inlet 613. The connecting pipe 62 is provided with a second inner cavity 621 communicated with the first inner cavity 611, and the second inner cavity 621 is communicated with the second cavity 54. The wall of the connecting pipe is provided with a plurality of air flow perforations 622. The curved plate 63 partially surrounds the swirl plate 612, so that the exhaust gas from the first opening 51 can pass through the curved plate 63 to enter the swirl tube 61 from the gas inlet 613. In the illustrated embodiment of the utility model, the arcuate plate 63 is C-shaped in cross-section. The center pin of arc 63 with the center pin of whirl pipe 61 is parallel, mixing chamber subassembly 4 is including being located arc 63 with the arc air current passageway between the whirl pipe 61.

The mixing chamber shell 5 is provided with a mounting seat 531 for mounting a urea nozzle 7, and the urea nozzle 7 is used for spraying atomized urea liquid drops into the cyclone tube 61.

The mixing chamber assembly 4 further includes a swirling device 8 located in the second chamber 54 and connected to the connecting tube 62. The cyclone device 8 comprises a top wall 81, a connecting wall 82 connected with the top wall 81, and a cyclone cavity 80 enclosed by the top wall 81 and the connecting wall 82. Specifically, the top wall 81 is provided with a mounting hole 810 communicating with the cyclone chamber 80, and the connection pipe 62 is partially inserted into the mounting hole 810. The wall of the connecting pipe 62 in the rotational flow cavity 80 is provided with the plurality of airflow perforations 622. The top wall 81 includes a first side 811 and a second side 812 opposite the first side 811. The connecting wall 82 extends downward from the second side 812 and toward the first side 811. The connecting wall 82 is provided with an arc-shaped inner wall surface 821 to facilitate the formation of the air flow swirling flow. The swirling device 8 comprises an airflow outlet 83 between the connecting wall 82 and the first side 811.

Furthermore, the mixing chamber arrangement 4 comprises a perforated plate 9 on the side of the swirling device 8 adjacent to the second aftertreatment carrier arrangement 2. The perforated plate 9 is fixed to the mixing chamber assembly 8 and the perforated plate 9 is suspended in the second chamber 54, i.e. the outer edge of the perforated plate 9 is not in contact with the mixing chamber housing 5, which creates enough space for the gas flow to flow out.

When in use, the tail gas of the diesel engine passes through the third aftertreatment carrier component 3 and the first aftertreatment carrier component 1 and enters the first cavity 53 through the first opening 51; since the arc plate 63 covers the cyclone plate 612 facing the first opening 51, the exhaust gas from the first opening 51 bypasses the arc plate 63 to enter the cyclone tube 61 through the gas inlet 613. With the arrangement, the tail gas flowing from the first opening 51 is prevented from directly rushing to the cyclone tube 61 in a large amount, so that the uneven distribution of the gas flow is caused, and the improvement of the anti-urea crystallization capacity is facilitated. In the process, most of the tail gas enters the cyclone tube 61 from the gas inlet 613 facing away from the first opening 51 on both sides or from the gas inlet 613 facing the first opening 51 through the arc-shaped gas passage. The tail gas is guided by the cyclone plate 612 to rotate and enter the cyclone tube 61; the off-gas and urea droplets mix in the cyclone tube 61 and form a downward swirling gas flow. The gas flow is guided by the connecting wall 82 to form a swirling flow, a part of the gas flow flows out from the gas flow outlet 83, and the other part of the gas flow passes directly through the perforated plate 9.

Compared with the prior art, the utility model increases the flow stroke of the airflow, particularly the mixing distance of the ammonia gas and the exhaust gas through the rotational flow device 8, thereby being beneficial to improving the uniformity of airflow mixing. This also contributes to an improved ammonia homogeneity at the inlet of the second aftertreatment support module 2.

The above embodiments are only for illustrating the utility model and not for limiting the technical solutions described in the utility model, and the understanding of the present specification should be based on the technical personnel in the field, and although the present specification has described the utility model in detail with reference to the above embodiments, the technical personnel in the field should understand that the technical personnel in the field can still make modifications or equivalent substitutions to the present invention, and all the technical solutions and modifications thereof without departing from the spirit and scope of the present invention should be covered in the claims of the present invention.

Claims

1. A mixing cavity assembly comprises a mixing cavity shell and a mixing tube assembly arranged in the mixing cavity shell, wherein the mixing cavity shell is provided with a first opening communicated with a first post-processing carrier assembly, a second opening communicated with a second post-processing carrier assembly, a first cavity communicated with the first opening and a second cavity communicated with the second opening; the mixing tube assembly comprises a swirl tube located in the first cavity and a connecting tube located in the second cavity; the cyclone tube is provided with a first inner cavity, a plurality of cyclone plates and an airflow inlet corresponding to the cyclone plates, the first inner cavity is communicated with the first cavity through the airflow inlet, the connecting tube is provided with a second inner cavity communicated with the first inner cavity, and the second inner cavity is communicated with the second cavity; the method is characterized in that: the mixing cavity assembly further comprises a rotational flow device which is located in the second cavity and connected with the connecting pipe, the rotational flow device comprises a rotational flow cavity, and the connecting pipe is at least partially inserted into the rotational flow cavity.

2. The mixing chamber assembly of claim 1, wherein: the cyclone device comprises a top wall, the top wall is provided with a mounting hole communicated with the cyclone cavity, and the connecting pipe is partially inserted into the mounting hole.

3. The mixing chamber assembly of claim 2, wherein: the top wall includes a first side and a second side opposite the first side, and the swirling device includes a connecting wall extending downward from the second side and toward near the first side.

4. The mixing chamber assembly of claim 3, wherein: the connecting wall is provided with an arc-shaped inner wall surface.

5. The mixing chamber assembly of claim 3, wherein: the swirling device comprises an airflow outlet between the connecting wall and the first side.

6. The mixing chamber assembly of claim 1, wherein: the mixing chamber assembly further includes a perforated plate located on a side of the swirling device adjacent the second aftertreatment carrier assembly.

7. The mixing chamber assembly of claim 6, wherein: the perforated plate is fixed to the mixing chamber assembly and is suspended in the second cavity.

8. The mixing chamber assembly of claim 1, wherein: and a plurality of airflow perforations are arranged on the pipe wall of the connecting pipe in the rotational flow cavity.

9. The mixing chamber assembly of claim 1, wherein: mix the pipe assembly and still including being located just partial encirclement in the first cavity the arc of spinning disk to make tail gas need walk around the arc just can be followed air inlet gets into the cyclone tube, the transversal C shape of personally submitting of arc.

10. An exhaust aftertreatment package comprising a first aftertreatment carrier component, a second aftertreatment carrier component, a third aftertreatment carrier component located upstream of the first aftertreatment carrier component, and a mixing chamber component connecting the first aftertreatment carrier component with the second aftertreatment carrier component, wherein the first aftertreatment carrier component is a diesel particulate trap, the second aftertreatment carrier component is a selective catalytic reduction agent, the third aftertreatment carrier component is a diesel oxidation catalyst, characterized in that: the mixing chamber assembly of any one of claims 1 to 9.