阅读说明：本技术 一种静态混风器 (Static air mixer ) 是由 孙瑞胜 张效伟 于 2019-11-22 设计创作，主要内容包括：本申请公开了一种静态混风器,利用文丘里结构引入回配风和助燃风,并在文丘里效应的作用下将二者进行完全混合,并时刻保持完全汇入状态,配合螺旋混风通道,使气流不断被揉合、混匀,达到均匀掺混降低氧含量并输出的效果,利用文丘里结构引入回配风和助燃风,并在文丘里效应的作用下将二者进行完全混合,并时刻保持完全汇入状态,配合螺旋混风通道,使气流不断被揉合、混匀,达到均匀掺混降低氧含量并输出的效果。(The application discloses static air mixer, utilize the venturi structure to introduce return air-distribution and combustion-supporting wind, and carry out the complete mixing with the two under the effect of venturi effect, and constantly keep the complete influx state, cooperation spiral air mixing channel, make the air current constantly kneaded, the mixing, reach the effect that even mixing reduced oxygen content and exported.)

1. The utility model provides a static air mixer which characterized in that, includes the trunk line, trunk line one end is detachable flange joint of blind flange. Be equipped with trompil and welded connection on the blind flange, cooperation trunk line forms the venturi structure, the venturi structure is with inside accepting room, mixing chamber and the diffusion chamber that divide into the axial and communicate in proper order of trunk line, accepting the room and being located the one end that the trunk line is close to the blind flange, the air-supply line is used for accepting the room with combustion-supporting wind input, and the intercommunication has the air distribution pipe on the trunk line lateral wall that the accepting room corresponds for in accepting the room with the back distribution wind input, the mixing chamber is received the back distribution wind and the combustion-supporting wind of diffusion chamber and is exported in the diffusion chamber after mixing it.

2. The static air mixer according to claim 1, further comprising a static air mixing structure, wherein the static air mixing structure has an air mixing channel inside, an air mixing unit is disposed in the air mixing channel for disturbing the air flow in the air mixing channel to form a turbulent effect, and one end of the diffusion chamber, which is far away from the mixing chamber, is communicated with the air mixing channel to discharge the mixed air in the diffusion chamber through the air mixing channel.

3. The static air mixer of claim 2, wherein the static air mixing structure comprises a plurality of left-handed units and a plurality of right-handed units for left-handed flow and right-handed flow of the air, respectively, and the left-handed units and the right-handed units are alternately arranged along the axial direction of the air mixing channel.

4. The static air mixer according to claim 3, wherein the air mixing unit is provided with a left helical blade and a right helical blade, the left helical blade is matched with the inner wall of the air mixing channel to form a left-handed unit, and the right helical blade is matched with the inner wall of the channel to form a right-handed unit.

5. The static air mixer according to any one of claims 2-4, wherein the static air mixing structure is in butt joint with the main pipeline through a flange, and the air mixing channel is arranged coaxially with the main pipeline.

6. The static air mixer of claim 1 wherein a nozzle is attached to one end of said air inlet duct, said nozzle extending into said receiving chamber, said nozzle being a conical nozzle opening into said mixing chamber.

7. The static air mixer according to claim 6, wherein the air distribution pipes are arranged along the radial direction of the main pipeline, the axes of the air distribution pipes are perpendicular to the axis of the main pipeline, the axes of the air distribution pipes are positioned between the nozzle openings and the air inlet pipes, and one ends of the air distribution pipes communicated with the receiving chamber face to the generatrix surface of the conical nozzles.

8. The static mixer of claim 1, wherein the mixing chamber communicates at one end with the receiving chamber through a first reducer section and communicates at the other end with the diffuser chamber through a second reducer section for forming an hourglass-shaped passage that contracts and then expands.

9. The static mixer of claim 8, wherein an axial length of the first reducer section is less than an axial length of the second reducer section.

Technical Field

The present application relates to a static air mixer.

Background

In practical engineering implementation, the situation of exhaust gas recirculation is often encountered, that is, exhaust gas with low oxygen content after combustion is mixed into combustion-supporting air in proportion to reduce the oxygen content of the combustion-supporting air, and the temperature of a combustion chamber is reduced to reduce the generation amount of thermal nitrogen oxides, that is, the so-called low-nitrogen combustion requires that the exhaust gas is uniformly mixed with the combustion-supporting air in proportion to effectively reduce the generation of NOx.

The inventor finds that the waste gas recirculation rate required by low-nitrogen combustion generally accounts for 15-20% of the over-fired air, and the waste gas is pressurized by a booster fan and then flows into a main combustion air pipeline; however, if the wind is directly merged, the two wind streams interfere with each other, the requirement of completely merging in proportion is difficult to achieve due to inconsistent pressure, even if the pressure is adjusted to be merged in a balanced manner as much as possible, the complete merging is difficult to achieve and the complete merging state is kept constantly due to the fluctuation of a pressure head of the centrifugal fan; as shown in fig. 1, in the conventional mixing method, after mixing, the mixed air flows in a laminar flow manner and cannot be uniformly mixed with combustion-supporting air, and due to fluctuation of return air flow and non-uniformity of a flow field, the low-nitrogen combustion effect is greatly reduced, so that the generation of NOx is difficult to effectively reduce, and the requirement of low-nitrogen combustion cannot be met.

Disclosure of Invention

The utility model aims at the defect that prior art exists, provide a static air mixer, utilize the venturi structure to introduce return air-distribution and combustion-supporting wind to mix the two completely under the effect of venturi effect, and keep constantly mixing the state completely, the cooperation spiral mixes the wind passageway, makes the air current constantly kneaded, the mixing, reaches the effect that even mixing reduces oxygen content and export.

In order to realize the purpose, the following technical scheme is adopted:

the utility model provides a static air mixer, includes the trunk line, trunk line one end is detachable flange cover flange joint, go up behind the trompil with air-supply line welded connection on the flange cover, the air-supply line stretches into and accepts room one end welding nozzle structure for make gas spray after accelerating get into and accept the room and cooperate the trunk line to form the venturi structure. Venturi structure is with inside accepting room, mixing chamber and the diffusion chamber that divide into the axial and communicate in proper order of trunk line, the accepting room is located the one end that the trunk line is close to the blind flange, the air-supply line is used for accepting the room with combustion-supporting wind input, and the intercommunication has the air distribution pipe on the trunk line lateral wall that the accepting room corresponds for in accepting the room with the return air input, the mixing chamber receives return air distribution and the combustion-supporting wind of diffusion chamber and exports the diffusion chamber in with it mixes the back.

Further, still include static structure of mixing wind, static structure of mixing wind inside has the passageway of mixing wind, be equipped with the unit of mixing wind in the passageway of mixing wind for the gas flow that disturbs in the passageway of mixing wind forms the torrent effect, the one end intercommunication passageway of mixing wind of mixing chamber is kept away from to the diffusion chamber, discharges the mist in the diffusion chamber through the passageway of mixing wind.

Furthermore, the static air mixing structure comprises a plurality of left-handed units and a plurality of right-handed units which are respectively used for enabling air to flow in a left-handed mode and flow in a right-handed mode, and the left-handed units and the right-handed units are alternately arranged along the axial direction of the air mixing channel.

Furthermore, the wind mixing unit is provided with a left helical blade and a right helical blade, the left helical blade is matched with the inner wall of the wind mixing channel to form a left-handed unit, and the right helical blade is matched with the inner wall of the channel to form a right-handed unit.

Further, the static air mixing structure is in butt joint with the main pipeline through a flange, and the air mixing channel is coaxially arranged with the main pipeline.

Furthermore, one end of the air inlet pipe is connected with a nozzle, the nozzle extends into the receiving chamber, the nozzle is a conical nozzle, and the opening of the nozzle faces the mixing chamber. So that the combustion air is accelerated at the nozzle and is injected into the receiving chamber at a higher speed, creating a venturi effect.

Furthermore, the air distribution pipes are arranged along the radial direction of the main pipeline, the axes of the air distribution pipes are perpendicular to the axis of the main pipeline, the axes of the air distribution pipes are positioned between the nozzle openings and the air inlet pipe, and one end of each air distribution pipe communicated with the receiving chamber faces to the generatrix surface of the conical nozzle.

Furthermore, one end of the mixing chamber is communicated with the receiving chamber through a first reducing section, the other end of the mixing chamber is communicated with the diffusion chamber through a second reducing section, the mixing chamber is used for forming an hourglass-shaped channel which is contracted and expanded firstly, and the axial length of the first reducing section is smaller than that of the second reducing section.

Compared with the prior art, the application has the advantages and positive effects that:

(1) the flange cover flange is detachably connected with the closed main pipeline to form a Venturi structure, so that combustion-supporting air and return air are completely input into the receiving chamber, then gas in the mixing chamber formed after the section is sharply contracted is compressed and gradually expanded in the diffusion section, and the mixing of the combustion-supporting air and the return air is accelerated by firstly contracting and then expanding, so that compared with the traditional mixing structure, the effects of keeping complete and continuous mixing and improving the mixing uniformity are achieved;

(2) the return air distribution outlet is vertical to the main pipe axis and enters the receiving chamber, the return air distribution and the combustion-supporting air cannot interfere with each other, and a negative pressure area is formed near the nozzle after the combustion-supporting air is injected at a high speed, so that the return air distribution is ensured to be continuously mixed through the air distribution pipe, and the return air distribution and the combustion-supporting air are ensured to be stably converged in proportion;

(3) the conical nozzle structure is adopted, the initial speed of combustion-supporting air entering the receiving chamber is increased, the combustion-supporting air faces a mixing chamber channel, the flowing speed is increased, a negative pressure area is formed near the nozzle, and the influx of return air is promoted;

(4) one or more static wind mixing structures are adopted to accelerate the mixing of the two, and by utilizing the structure that the left-handed units and the right-handed units are alternately arranged, gas is reflected when flowing through a cavity formed by the helical blades and the static wind mixing structures, and vortex is generated. The laminar flow structure of the two gases is broken, and the two gases are continuously mixed by the turbulent flow effect; the left-right rotating alternating structure enables the gas flow direction to be changed continuously, the turbulent flow effect is further intensified, two gas flows form the turbulent flow effect when passing through the air mixing channel, and the two gas flows are kneaded and uniformly mixed continuously, so that the two gas flows are mixed together completely and uniformly; this turbulence effect will increase with increasing helix angle, but the drag will also increase; generally, the pitch is increased to increase the length of the air mixing chamber, and the air mixing chamber is not too large and too large, and can be completely and uniformly mixed after passing through 3-8 groups of left and right rotary air mixing units; the mixture is supplied to a combustion chamber, thereby realizing the effects of reducing the oxygen content and reducing the generation amount of thermal NOx;

(5) two sections of variable-diameter sections with different axial lengths are adopted to form a variable-diameter section channel with a shorter front part and a longer rear part, so that the mixed air generates a turbulent flow effect in the variable-diameter sections at the two ends, and the effect of the uniform degree of mixing is improved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate embodiments of the application and, together with the description, serve to explain the application and are not intended to limit the application.

FIG. 1 is a schematic view of a conventional wind mixing structure as indicated in the background art;

fig. 2 is a schematic overall structure diagram of a static air mixer in embodiment 1 of the present application.

The device comprises an air inlet pipe 1, an air inlet pipe 2, a nozzle 3, a mixing chamber 4, a diffusion chamber 5, a right-handed unit 6, a left-handed unit 7, a static air mixing structure 8, an air distribution pipe 9, a receiving chamber 10, a negative pressure area 11, a butt flange 12 and a flange plate.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments according to the present application. As used herein, the singular forms "a", "an", and/or "the" are intended to include the plural forms as well, and it should be understood that when the terms "comprises" and/or "comprising" are used in this specification, they specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof;

for convenience of description, the words "up", "down", "left" and "right" in this application, if any, merely indicate correspondence with the directions of up, down, left and right of the drawings themselves, and do not limit the structure, but merely facilitate the description of the invention and simplify the description, and do not indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the application.

The terms "mounted", "connected", "fixed", and the like in the present application should be understood broadly, and for example, the terms "mounted", "connected", and "fixed" may be fixedly connected, detachably connected, or integrated; the two components can be connected mechanically or electrically, directly or indirectly through an intermediate medium, or connected internally or in an interaction relationship, and the terms used in the present invention should be understood as having specific meanings to those skilled in the art.

As introduced in the background art, in the prior art, the pressurized air is converged into a main combustion air pipeline through a booster fan; however, if the wind is directly merged, the two wind streams interfere with each other, the requirement of completely merging in proportion is difficult to achieve due to inconsistent pressure, even if the pressure is adjusted to be merged in a balanced manner as much as possible, the complete merging is difficult to achieve and the complete merging state is kept constantly due to the fluctuation of a pressure head of the centrifugal fan; as shown in fig. 1, in the conventional mixing manner, after mixing, the air flows in a laminar flow manner and cannot be uniformly mixed with combustion-supporting air, and due to fluctuation of return air flow and nonuniformity of a flow field, the low-nitrogen combustion effect is greatly reduced, so that the generation of NOx is difficult to effectively reduce, and the requirement of low-nitrogen combustion cannot be met.