阅读说明：本技术 一种国六柴油机用可拆卸式尿素混合结构 (Detachable urea mixed structure for national six diesel engine ) 是由 许二丰 赵宜斌 吴鹏 徐敬明 王牧苏 王滨滨 韩永哲 于 2021-08-19 设计创作，主要内容包括：本发明公开了一种国六柴油机用可拆卸式尿素混合结构,包括进气法兰、混合器筒体、进气隔板、不锈钢缠绕网总成、出气隔板和出气法兰；所述进气法兰和所述出气法兰安装在混合器筒体的两端；所述进气隔板和所述出气隔板均为中部向外隆起的圆形片状结构,所述进气隔板和所述出气隔板径向安装在混合器筒体的中部并形成混合腔体；所述不锈钢缠绕网总成安装在混合腔体中部,将混合腔体分为两个部分；在混合腔体处的混合器筒体外侧安装有喷嘴座；所述混合器筒体上安装有温度传感器底座和压差取气底座。本发明结构紧凑,适用于对结构空间要求比较高的后处理器,可保证尿素与汽车尾气充分混合,明显的降低排气污染物浓度,对于抗尿素结晶方面有显著的效果。(The invention discloses a detachable urea mixing structure for a national six-diesel engine, which comprises an air inlet flange, a mixer barrel, an air inlet partition plate, a stainless steel winding net assembly, an air outlet partition plate and an air outlet flange; the air inlet flange and the air outlet flange are arranged at two ends of the mixer barrel; the air inlet partition plate and the air outlet partition plate are both of circular sheet structures with the middle parts protruding outwards, and the air inlet partition plate and the air outlet partition plate are radially arranged in the middle of the mixer barrel to form a mixing cavity; the stainless steel winding net assembly is arranged in the middle of the mixing cavity and divides the mixing cavity into two parts; a nozzle seat is arranged on the outer side of the mixer cylinder at the mixing cavity; and the mixer barrel is provided with a temperature sensor base and a differential pressure gas taking base. The invention has compact structure, is suitable for the post-processor with higher requirement on structural space, can ensure that urea and automobile exhaust are fully mixed, obviously reduces the concentration of exhaust pollutants, and has obvious effect on the aspect of resisting urea crystallization.)

1. A detachable urea mixing structure for a national six-diesel engine comprises an air inlet flange, a mixer barrel, an air inlet partition plate, a stainless steel winding net assembly, an air outlet partition plate and an air outlet flange; the method is characterized in that: the air inlet flange and the air outlet flange are arranged at two ends of the mixer barrel; the air inlet partition plate and the air outlet partition plate are both of circular sheet structures with the middle parts protruding outwards, and the air inlet partition plate and the air outlet partition plate are radially arranged in the middle of the mixer barrel to form a mixing cavity; the stainless steel winding net assembly is arranged in the middle of the mixing cavity and divides the mixing cavity into two parts; a nozzle seat is arranged on the outer side of the mixer cylinder at the mixing cavity; and the mixer barrel is provided with a temperature sensor base and a differential pressure gas taking base.

2. The detachable urea mixing structure for the six diesel engines in China according to claim 1, characterized in that: the air inlet partition plate and the air outlet partition plate are respectively provided with a plurality of air inlets and air outlets for air inlet and air outlet turbulence.

3. The detachable urea mixing structure for the six diesel engines in China according to claim 1, characterized in that: the edge of the air inlet partition plate and the edge of the air outlet partition plate are provided with flanges, so that the air inlet partition plate and the air outlet partition plate can be conveniently welded with a mixer cylinder.

4. The detachable urea mixing structure for the six diesel engines in China according to claim 1, characterized in that: the stainless steel winding net assembly is composed of a stainless steel wire winding net and an outer layer fixing pipe, and the stainless steel wire winding net is formed by winding a cylindrical stainless steel wire net after wavy indentations.

Technical Field

The invention belongs to the technical fields of automobile engine exhaust emission purification technology and energy conservation and consumption reduction, and particularly relates to a detachable urea mixing structure for a national six-diesel engine.

Background

The current mainstream technical route of the national heavy diesel engine is formed by combining an oxidation catalytic unit (DOC), a particle trapping unit (DPF), a selective catalytic reduction conversion unit (SCR) and an ammonia oxidation catalytic unit (ASC) in series, the structural arrangement is compact, and the urea mixing distance is short, so that the national heavy diesel engine is more complex in post-treatment compared with the national heavy diesel engine in the prior art, and has higher requirement on urea crystallization resistance. In order to meet the requirements of the diesel vehicle in China, a mixing structure which is relatively smaller in structure volume and more uniform in urea mixing needs to be designed.

Disclosure of Invention

The invention provides a detachable urea mixing structure for a national six-diesel engine, which has a compact structure, is widely suitable for arrangement of a national six-postprocessor, particularly, can ensure that urea and automobile exhaust are fully mixed, obviously reduces the concentration of exhaust pollutants, and has a remarkable effect on the aspect of resisting urea crystallization.

The technical scheme adopted by the invention is as follows: a detachable urea mixing structure for a national six-diesel engine comprises an air inlet flange, a mixer barrel, an air inlet partition plate, a stainless steel winding net assembly, an air outlet partition plate and an air outlet flange; the air inlet flange and the air outlet flange are arranged at two ends of the mixer barrel; the air inlet partition plate and the air outlet partition plate are both of circular sheet structures with the middle parts protruding outwards, and the air inlet partition plate and the air outlet partition plate are radially arranged in the middle of the mixer barrel to form a mixing cavity; the stainless steel winding net assembly is arranged in the middle of the mixing cavity and divides the mixing cavity into two parts; a nozzle seat is arranged on the outer side of the mixer cylinder at the mixing cavity; and the mixer barrel is provided with a temperature sensor base and a differential pressure gas taking base.

Furthermore, a plurality of air inlets and air outlets are respectively arranged on the air inlet clapboard and the air outlet clapboard and are used for air inlet and air outlet turbulence.

Furthermore, the edges of the air inlet partition plate and the air outlet partition plate are provided with flanges, so that the air inlet partition plate and the air outlet partition plate can be conveniently welded with a mixer cylinder.

Further, stainless steel winding net assembly comprises stainless steel wire winding net and outer fixed pipe, stainless steel wire winding net is twined after the wave indentation by columniform stainless steel wire net and forms.

The invention has the following beneficial effects:

1. the air inlet partition plate and the air outlet partition plate can be processed by the same set of die, so that the economy is good;

2. the assembly structure is simple, the air inlet and outlet partition plate and the stainless steel winding net assembly can be integrally plugged into the cylinder after being welded, and the production efficiency is improved;

3. the occupied space is small, the application range is wide, and the device can be suitable for arrangement of various post-processors by adjusting the diameters of the cylinder and the mixing cavity;

4. the urea is mixed more uniformly, the crystallization risk is lower, and the conversion efficiency of nitrogen oxides in tail gas is higher;

5. convenient disassembly and good maintainability.

Drawings

The invention is further described below with reference to the accompanying drawings.

FIG. 1 is a general schematic view of the intake direction of a hybrid structure;

FIG. 2 is a general schematic view of the air outlet direction of the hybrid structure;

FIG. 3 is a schematic internal view of a hybrid architecture;

FIG. 4 is a schematic view of the structure of the inlet end of the mixing chamber;

FIG. 5 is a schematic view of the structure of the outlet end of the mixing chamber;

FIG. 6 is an isometric view of a mixing chamber;

FIG. 7 is a schematic structural view of a stainless steel wound mesh assembly;

FIG. 8 is a side cross-sectional view of a stainless steel wound mesh assembly;

in the figure: 1-an air inlet flange, 2-an air inlet baffle plate, 3-a stainless steel winding net assembly, 4-a mixer barrel, 5-an air outlet baffle plate, 6-an air outlet flange, 7-a nozzle seat, 8-a differential pressure air taking base, 9-a temperature sensor base, 10-a stainless steel wire winding net and 11-an outer layer fixing pipe.

Detailed Description

The invention is further described with reference to the following figures and specific embodiments.

As shown in fig. 1 and 2, the invention provides a detachable urea mixing structure for a national diesel engine, the mixing structure is arranged at the rear end of a particle trap and at the front end of a selective catalytic reduction converter, and tail gas directly enters a mixer after passing through the particle trap to be mixed with urea spray.

As shown in fig. 3, the mixer includes an air inlet flange 1, an air inlet partition plate 2, a stainless steel winding net assembly 3, a mixer cylinder 4, an air outlet partition plate 5, an air outlet flange 6, a nozzle holder 7, a differential pressure air intake base 8 and a temperature sensor base 9.

Air inlet flange 1 and air outlet flange 6 are welded respectively at the both ends of blender barrel 4, and air inlet flange 1 and air outlet flange 6 are detachable flanges, the later stage of being convenient for is dismantled and is maintained. The air inlet partition plate 2 and the air outlet partition plate 5 are circular sheet structures with the middle parts bulging outwards, the air inlet partition plate 2 and the air outlet partition plate 5 are radially assembled in the middle of the mixer barrel 4 to form a cylindrical mixing cavity, and flanges are arranged at the edges of the air inlet partition plate 2 and the air outlet partition plate 5 and are convenient to weld in the mixer barrel 4 as shown in fig. 6. As shown in fig. 4 and 5, the air inlet partition 2 and the air outlet partition 5 are respectively provided with two air inlets and two air outlets for air inlet turbulent flow and air outlet turbulent flow. The differential pressure gas taking base 8 and the temperature sensor base 9 are arranged on the mixer cylinder 4, so that the rear end pressure of the particle catcher can be conveniently tested, the exhaust temperature can be conveniently monitored, and the urea injection amount can be better controlled.

As shown in fig. 7 and 8, the stainless steel winding net assembly 3 is formed by welding a stainless steel wire winding net 10 and an outer layer fixing pipe 11 by a brazing process, and the stainless steel wire winding net 10 is formed by winding a cylindrical stainless steel wire net after wavy indentations. The outer side of the outer layer fixing pipe 11 is welded, and the stainless steel winding net assembly 3 is fixed in the mixing cavity, so that the mixing cavity is divided into two parts. Meanwhile, the stainless steel wire winding net 10 can be replaced by a high-porosity structure such as a foam metal, a metal carrier and the like.

The nozzle holder 7 is arranged on the outer side of the mixer barrel 4 at the mixing cavity, and after the mixing cavity is integrally pressed into the mixer barrel 4, the central line of the mixing cavity is coincided with the central line of the nozzle holder 7. The differential pressure gas taking base 8 and the temperature sensor base 9 are welded on the mixer barrel 4; after the air outlet clapboard, a spoiler can be added according to the requirement to improve the uniformity of the flow field.

When the device is used, tail gas passes through the particle catcher, is divided into two parts through the upper air inlet hole of the air inlet partition plate 2 and enters the mixing cavity, and the tail gas is mixed with urea solution sprayed by a nozzle arranged on the nozzle seat 7 in the mixing cavity and passes through the stainless steel wire winding net 10 together. When the mist passes through stainless steel wire winding net 10, the stainless steel winding net of high temperature makes further breakage of liquid urea solution, evaporation, hydrolyzes to the ammonia, tail gas and ammonia mix the back and at the vortex of mixing chamber below, and the venthole reposition of redundant personnel to both sides of giving vent to anger baffle 5 below is walked around out, and the mixing distance of multiplicable tail gas of this mode and ammonia to make liquid spraying and gaseous state tail gas intensive mixing back by the end of giving vent to anger and arrange the selectivity catalytic reduction conversion unit to the rear end, carry out follow-up catalytic reaction.

It should be noted that the above-mentioned embodiments illustrate rather than limit the technical solutions of the present invention, and that equivalent substitutions or other modifications made by persons skilled in the art according to the prior art are included in the scope of the claims of the present invention as long as they do not exceed the spirit and scope of the technical solutions of the present invention.