CN110953045A - Mixer assembly for a ship's aircraft exhaust aftertreatment system - Google Patents

Mixer assembly for a ship's aircraft exhaust aftertreatment system Download PDF

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Publication number
CN110953045A
CN110953045A CN201911259735.5A CN201911259735A CN110953045A CN 110953045 A CN110953045 A CN 110953045A CN 201911259735 A CN201911259735 A CN 201911259735A CN 110953045 A CN110953045 A CN 110953045A
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CN
China
Prior art keywords
exhaust pipe
mixer
wall
exhaust
guide vanes
Prior art date
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Pending
Application number
CN201911259735.5A
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Chinese (zh)
Inventor
陈霍
蒋得刚
王智晶
华晨
马纪权
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Suzhou Nse Automotive Electronics Co ltd
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Suzhou Nse Automotive Electronics Co ltd
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Publication date
Application filed by Suzhou Nse Automotive Electronics Co ltd filed Critical Suzhou Nse Automotive Electronics Co ltd
Priority to CN201911259735.5A priority Critical patent/CN110953045A/en
Publication of CN110953045A publication Critical patent/CN110953045A/en
Pending legal-status Critical Current

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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/18Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control
    • F01N3/20Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by methods of operation; Control specially adapted for catalytic conversion ; Methods of operation or control of catalytic converters
    • F01N3/2066Selective catalytic reduction [SCR]
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N3/00Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust
    • F01N3/24Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous by thermal or catalytic conversion of noxious components of exhaust characterised by constructional aspects of converting apparatus
    • F01N3/28Construction of catalytic reactors
    • F01N3/2892Exhaust flow directors or the like, e.g. upstream of catalytic device
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2570/00Exhaust treating apparatus eliminating, absorbing or adsorbing specific elements or compounds
    • F01N2570/14Nitrogen oxides
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01NGAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL COMBUSTION ENGINES
    • F01N2610/00Adding substances to exhaust gases
    • F01N2610/02Adding substances to exhaust gases the substance being ammonia or urea

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  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Health & Medical Sciences (AREA)
  • Toxicology (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Exhaust Gas After Treatment (AREA)

Abstract

The invention discloses a mixer assembly for a ship engine exhaust aftertreatment system, which comprises a first exhaust pipe, a second exhaust pipe, a nozzle, a primary mixer and a secondary mixer, wherein the first exhaust pipe is communicated with the second exhaust pipe; a nozzle is arranged on the side wall of the front end of the first exhaust pipe, a second exhaust pipe is arranged at the rear end of the first exhaust pipe, and urea solution is atomized by the nozzle and then sprayed into the first exhaust pipe to be mixed with tail gas, and then enters the second exhaust pipe; a first-stage mixer and a second-stage mixer are sequentially arranged in the second exhaust pipe from the front end to the rear end, and the first-stage mixer is used for guiding the fluid in the second exhaust pipe to the periphery of the inner wall of the second exhaust pipe; the secondary mixer is used to direct the advancing fluid into a rotational motion. The mixer assembly for the ship engine exhaust aftertreatment system disclosed by the invention is reasonable in design, compact in structure and good in uniformity of mixing of the reactant and the tail gas.

Description

Mixer assembly for a ship's aircraft exhaust aftertreatment system
Technical Field
The invention relates to the technical field of marine diesel engine tail gas treatment, in particular to a mixer assembly for a marine engine exhaust aftertreatment system.
Background
Selective Catalytic Reduction (SCR) is a treatment process for NOx in exhaust gas emission of diesel engines, namely, under the action of a catalyst, a reducing agent ammonia or urea solution is sprayed to reduce NOx in the exhaust gas into N2 and H2O. Specifically, tail gas of the diesel engine enters an exhaust mixing pipe after coming out of a turbine, a urea metering injection device is installed on the mixing pipe, urea aqueous solution is injected, urea is hydrolyzed and pyrolyzed at high temperature to generate NH3, NOx is reduced on the surface of a catalyst of an SCR system by NH3, N2 is discharged, and redundant NH3 is oxidized into N2.
At present, SCR has the advantages of good economic benefit, small change on a diesel engine, high NOx conversion rate, insensitivity to sulfur, wide application range and the like, and is considered to be the most feasible NOx emission control post-treatment technology of the diesel engine, and the key influencing factor of the SCR is the mixing uniformity degree of NH3 and tail gas except for a catalyst, so an air inlet pipeline of an SCR system is particularly important in the whole pipeline system.
However, the existing exhaust mixing structure for the exhaust aftertreatment of the marine diesel engine has the problems of unreasonable structural design and poor mixing uniformity of a reactant and the exhaust.
Disclosure of Invention
Therefore, the invention provides a mixer assembly for a ship engine exhaust aftertreatment system, which aims to solve the problems that in the prior art, the design of an exhaust mixing structure for ship engine diesel engine exhaust aftertreatment is unreasonable, and the mixing uniformity of a reactant and exhaust is poor.
In order to achieve the above purpose, the invention provides the following technical scheme:
the invention provides a mixer assembly for a ship engine exhaust aftertreatment system, which comprises a first exhaust pipe, a second exhaust pipe, a nozzle, a primary mixer and a secondary mixer, wherein the first exhaust pipe is communicated with the second exhaust pipe;
a nozzle is arranged on the side wall of the front end of the first exhaust pipe, a second exhaust pipe is arranged at the rear end of the first exhaust pipe, and urea solution is atomized by the nozzle and then sprayed into the first exhaust pipe to be mixed with tail gas, and then enters the second exhaust pipe;
a first-stage mixer and a second-stage mixer are sequentially arranged in the second exhaust pipe from the front end to the rear end, and the first-stage mixer is used for guiding the fluid in the second exhaust pipe to the periphery of the inner wall of the second exhaust pipe; the secondary mixer is used to direct the advancing fluid into a rotational motion.
Preferably, the first-stage mixer comprises a set of first fins comprising a first fixed bracket and first guide vanes; the first fixing support is arranged along the radial direction of the second exhaust pipe, and two ends of the first fixing blade are respectively fixed on the inner wall of the second exhaust pipe; the two first guide vanes are respectively fixed on two sides of the first fixing support and extend towards the inner wall of the second exhaust pipe, an included angle is formed between each first guide vane and the first fixing support, and the two first guide vanes guide fluid in the second exhaust pipe to the periphery of the inner wall of the second exhaust pipe;
or the first-stage mixer comprises a plurality of groups of first fins, each group of first fins comprises a first fixed support and first guide vanes, the first fixed supports are arranged along the radial direction of the second exhaust pipe, two ends of each first fixed vane are respectively fixed on the inner wall of the second exhaust pipe, and the first fixed supports are fixedly arranged along the axis of the second exhaust pipe in a crossed manner; every two ends of the first fixing support are respectively fixed with two first guide vanes extending towards the inner wall of the second exhaust pipe, the two first guide vanes are respectively positioned on two sides of the first fixing support and form included angles with the first fixing support, and the first guide vanes guide fluid in the second exhaust pipe to the periphery of the inner wall of the second exhaust pipe.
Preferably, the primary mixer comprises four sets of first fins or six sets of first fins.
Preferably, the first guide vane is provided with a plurality of openings;
or the outer surface of the first guide vane is provided with a drainage groove.
Preferably, the included angle between the first guide vane and the first fixing support is 30-60 degrees, and the length of one end, close to the first fixing support, of the first guide vane is greater than the length of one end, far away from the first fixing support, of the first guide vane.
Preferably, the second-stage mixer includes a plurality of second guide vanes, and is a plurality of second guide vane all is fixed in the inner wall of second blast pipe and to the axis of second blast pipe extends, and is a plurality of second guide vane follows the circumference of the inner wall of second blast pipe distributes and with the axis of second blast pipe is the contained angle, second guide vane guides the fluid that moves forward and takes place rotary motion.
Preferably, the included angle between the second guide vane and the axis of the second exhaust pipe is 30-60 °.
Preferably, the second-stage mixer further includes a plurality of second fixing brackets, the plurality of second fixing brackets and the plurality of second guide vanes are arranged in a one-to-one correspondence manner, and each of the second guide vanes is fixed to the inner wall of the second exhaust pipe through the corresponding second fixing bracket.
Preferably, the second fixing bracket is welded to an inner wall of the second exhaust pipe.
Preferably, a space is arranged between the first-stage mixer and the second-stage mixer.
The invention has the following advantages:
the invention provides a mixer assembly for a ship engine exhaust aftertreatment system, which comprises a first exhaust pipe, a second exhaust pipe, a nozzle, a primary mixer and a secondary mixer. Firstly, tail gas passes through a first exhaust pipe, and meanwhile, urea solution is sprayed into the first exhaust pipe after being atomized by a nozzle to be evaporated and is preliminarily mixed with the tail gas; secondly, the exhaust in the second exhaust pipe is dispersed to the periphery of the second exhaust pipe through the primary mixer, so that mutual collision and enlargement among liquid drops are avoided, the mixing uniformity of urea and tail gas is preliminarily improved, the crystallization risk can be reduced, and meanwhile, a part of liquid drops are crushed when colliding with the first guide fin, so that the evaporation of the urea liquid drops can be accelerated; secondly, the exhaust gas in the second exhaust pipe can be fully mixed and evaporated when passing through a pipeline between the first-stage mixer and the second-stage mixer; and then, the exhaust gas forms strong rotational flow through the second guide vanes, and the rest part of liquid drops collide and are crushed with the second vanes again, so that the urea particles are further promoted to be evaporated and pyrolyzed quickly, the risk of generating a large-area liquid film and generating crystallization is avoided, and the mixing uniformity of the urea and the tail gas is further improved.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below. It should be apparent that the drawings in the following description are merely exemplary, and that other embodiments can be derived from the drawings provided by those of ordinary skill in the art without inventive effort.
The structures, ratios, sizes, and the like shown in the present specification are only used for matching with the contents disclosed in the specification, so that those skilled in the art can understand and read the present invention, and do not limit the conditions for implementing the present invention, so that the present invention has no technical significance, and any structural modifications, changes in the ratio relationship, or adjustments of the sizes, without affecting the functions and purposes of the present invention, shall fall within the scope covered by the technical contents disclosed in the present invention.
FIG. 1 is a schematic illustration of a first exhaust pipe of a mixer assembly for an exhaust aftertreatment system of a marine vessel according to an embodiment of the invention;
FIG. 2 is a schematic diagram of a second exhaust pipe of a mixer assembly for an exhaust aftertreatment system of a marine vessel according to an embodiment of the invention;
FIG. 3 is a front view of FIG. 2;
FIG. 4 is a rear view of FIG. 2;
FIG. 5 is a schematic structural diagram of a primary mixer and a secondary mixer of a mixer assembly for an exhaust aftertreatment system of a ship engine according to an embodiment of the invention;
FIG. 6 is a schematic block diagram of an alternate view of a primary mixer and a secondary mixer of a mixer assembly for an exhaust aftertreatment system of a marine vessel according to an embodiment of the invention;
FIG. 7 is a schematic flow diagram of a fluid in a first mixer section of a mixer assembly for a marine exhaust aftertreatment system according to an embodiment of the invention;
FIG. 8 is a schematic flow diagram of a fluid in a two-stage mixer section of a mixer assembly for a marine exhaust aftertreatment system according to an embodiment of the invention;
FIG. 9 is a cross-sectional swirl flow schematic of the aft end of a first exhaust pipe of a mixer assembly for a marine exhaust aftertreatment system in accordance with an embodiment of the present invention;
in the figure: 1. a first exhaust pipe; 2. a second exhaust pipe; 3. a nozzle; 4. a first-stage mixer; 41. a first fin; 401. a first fixed bracket; 402. a first guide vane; 5. a secondary mixer; 51. a second guide vane 52 and a second fixed bracket.
Detailed Description
The present invention is described in terms of particular embodiments, other advantages and features of the invention will become apparent to those skilled in the art from the following disclosure, and it is to be understood that the described embodiments are merely exemplary of the invention and that it is not intended to limit the invention to the particular embodiments disclosed. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
As shown in fig. 1 to 6, the present embodiment provides a mixer assembly for a ship engine exhaust gas after-treatment system, which includes a first exhaust pipe 1, a second exhaust pipe 2, a nozzle 3, a primary mixer 4, and a secondary mixer 5.
Specifically, a nozzle 3 is installed on the side wall of the front end of the first exhaust pipe 1, a second exhaust pipe 2 is installed at the rear end of the first exhaust pipe 1, and urea solution is atomized by the nozzle 3 and sprayed into the first exhaust pipe 1 to be mixed with tail gas, and then enters the second exhaust pipe 2. It should be noted that the nozzle 3 is preferably a porous gas-assisted nozzle 3 which can atomize the urea solution. The nozzle 3 needs to extend into the first exhaust pipe 1 and spray the atomized urea solution into the axis of the first exhaust pipe 1, so that the urea solution and the tail gas can be conveniently mixed and flow to the second exhaust pipe 2.
More specifically, a first-stage mixer 4 and a second-stage mixer 5 are sequentially arranged in the second exhaust pipe 2 from the front end to the rear end, and the first-stage mixer 4 is used for guiding the fluid in the second exhaust pipe 2 to the periphery of the inner wall of the second exhaust pipe 2; the secondary mixer 5 is used to direct the advancing fluid into a rotational motion.
Preferably, the primary mixer 4 comprises a set of first fins 41, the first fins 41 comprising first fixing brackets 401 and first guide vanes 402; the first fixing bracket 401 is arranged along the radial direction of the second exhaust pipe 2, and both ends of the first fixing blade are respectively fixed to the inner wall of the second exhaust pipe 2; two first guide vanes 402 are fixed on two sides of the first fixing bracket 401 respectively and extend towards the inner wall of the second exhaust pipe 2, an included angle is formed between the first guide vanes 402 and the first fixing bracket 401, and the two first guide vanes 402 guide the fluid in the second exhaust pipe 2 to the periphery of the inner wall of the second exhaust pipe 2, so that the urea and the tail gas are mixed uniformly primarily when being guided to the periphery of the inner wall of the second exhaust pipe 2 by the first guide vanes 402.
In another preferred embodiment, the first-stage mixer 4 includes multiple sets of first fins 41, each set of first fins 41 includes a first fixing bracket 401 and a first guide vane 402, the first fixing bracket 401 is disposed along the radial direction of the second exhaust pipe 2, two ends of the first fixing vane are respectively fixed to the inner wall of the second exhaust pipe 2, and the multiple first fixing brackets 401 are fixedly disposed along the axis of the second exhaust pipe 2 in a crossed manner; two ends of each first fixing bracket 401 are respectively fixed with two first guide vanes 402 extending to the inner wall of the second exhaust pipe 2, and the two first guide vanes 402 are respectively located at two sides of the first fixing bracket 401 and form an included angle with the first fixing bracket 401, and the plurality of first guide vanes 402 guide the fluid in the second exhaust pipe 2 to the periphery of the inner wall of the second exhaust pipe 2, referring to fig. 7, so that the urea and the tail gas are primarily mixed uniformly when being guided to the periphery of the inner wall of the second exhaust pipe 2 by the first guide vanes 402.
In this embodiment, the primary mixer 4 includes four sets of first fins 41 or six sets of first fins 41, which enables the exhaust gas and the urea to be mixed more sufficiently, and the mixing effect is better.
Preferably, the first guide vane 402 is provided with a plurality of openings; alternatively, the outer surface of the first guide vane 402 is provided with a drainage groove, which facilitates further thorough mixing of urea and exhaust gas.
Further preferably, an included angle between the first guide vane 402 and the first fixing bracket 401 is 30 ° to 60 °, and a length of one end of the first guide vane 402 close to the first fixing bracket 401 is greater than a length of one end of the first guide vane 402 away from the first fixing bracket 401, which facilitates a flow of the fluid in the second exhaust pipe 2 and a flow of the fluid to the periphery of the inner wall of the second exhaust pipe 2.
Referring to fig. 8 and 9, the second-stage mixer 5 includes a plurality of second guide vanes 51, the plurality of second guide vanes 51 are all fixed to the inner wall of the second exhaust pipe 2 and extend towards the axis of the second exhaust pipe 2, the plurality of second guide vanes 51 are distributed along the circumferential direction of the inner wall of the second exhaust pipe 2 and form an included angle with the axis of the second exhaust pipe 2, the second guide vanes 51 guide the forward fluid to rotate, urea and tail gas pass through the first-stage mixer 4 and the second-stage mixer 5, urea is pyrolyzed and hydrolyzed to produce NH3, the tail gas and NH3 are fully mixed, the mixed tail gas enters the purifier, NOx reacts with NH3 to produce N2 and H2O. The exhaust gas forms strong rotational flow through the second guide vanes 51, and the rest part of liquid drops collide and are crushed with the second vanes again, so that the urea particles are further promoted to be evaporated and pyrolyzed quickly, the risk of generating a large-area liquid film and generating crystallization is avoided, and the mixing uniformity of the urea and the tail gas is further improved.
Referring to fig. 6, the second guide vane 51 forms an angle of 30 ° to 60 ° with the axis of the second exhaust pipe 2, which facilitates the exhaust gas to form strong swirling flow through the second guide vane 51.
It should be noted that characteristic parameters of the first-stage mixer 4 and the second-stage mixer 5, such as the fin angle, the number of swirl blades, the distance between the two, and the like, can be adjusted according to the internal arrangement space of the second exhaust pipe 2. Meanwhile, the primary mixer 4 and the secondary mixer 5 can be formed by punching from a plate material.
Preferably, the second-stage mixer 5 further includes a plurality of second fixing brackets 52, the plurality of second fixing brackets 52 and the plurality of second guide vanes 51 are disposed in a one-to-one correspondence, each second guide vane 51 is fixed to the inner wall of the second exhaust pipe 2 through the corresponding second fixing bracket 52, and the second fixing bracket 52 facilitates the fixing of the second guide vane 51.
Further preferably, the second fixing bracket 52 is welded to the inner wall of the second exhaust pipe 2, which makes the fixing of the second fixing bracket 52 to the second exhaust pipe 2 more stable.
In this embodiment, a distance is provided between the first-stage mixer 4 and the second-stage mixer 5, and the arrangement distance between the first-stage mixer 4 and the second-stage mixer 5 needs to take a reasonable value according to the whole arrangement and the flow condition, so that the first-stage mixer 4 and the second-stage mixer 5 can fully mix urea and tail gas.
It should be noted that CFD, a comprehensive fluid dynamics in english, is a branch of fluid dynamics, and is abbreviated as CFD. CFD is the product of a combination of modern hydrodynamics, numerical mathematics and computer science, a powerful cross-science. The method uses an electronic computer as a tool, applies various discretized mathematical methods, and performs numerical experiments, computer simulation and analytical research on various problems of fluid mechanics to solve various practical problems. As shown in fig. 7 to 9, the CFD calculation shows that both the two mixer sections and the downstream section have stronger swirling flow. Through the enhancement of the rotational flow of the first-stage mixer 4 and the second-stage mixer 5, the downstream of the second-stage mixer 5 still has strong rotational flow effect.
It is emphasized that, because the diameter of the exhaust pipe of the ship is relatively large, the uniformity of the ammonia gas around the exhaust pipe is poor, and the secondary mixer 5 is needed to enhance the evaporative pyrolysis of the spray and improve the uniformity of the ammonia gas.
According to the mixer assembly for the ship engine exhaust aftertreatment system, firstly, tail gas passes through the first exhaust pipe 1, and meanwhile, urea solution is sprayed into the first exhaust pipe 1 after being atomized by the nozzle 3 to be evaporated and is primarily mixed with the tail gas; secondly, the exhaust in the second exhaust pipe 2 is dispersed to the periphery of the second exhaust pipe 2 through the primary mixer 4, so that mutual collision and enlargement among liquid drops are avoided, the mixing uniformity of urea and tail gas is preliminarily improved, the crystallization risk can be reduced, and meanwhile, a part of liquid drops are crushed when colliding with the first guide fins, so that the evaporation of the urea liquid drops can be accelerated; secondly, the exhaust gas in the second exhaust pipe 2 can be fully mixed and evaporated when passing through a pipeline between the first-stage mixer 4 and the second-stage mixer 5; and then, the exhaust gas forms strong rotational flow through the second guide vanes 51, and the rest part of liquid drops collide and are crushed with the second vanes again, so that the urea particles are further promoted to be evaporated and pyrolyzed quickly, the risk of generating a large-area liquid film and generating crystallization is avoided, and the mixing uniformity of the urea and the tail gas is further improved. The mixing through the first-stage mixer 4 and the second-stage mixer 5 greatly improves the mixing effect, effectively solves the problem of ammonia nonuniformity, and effectively reduces the risk of urea crystallization.
Therefore, the mixer assembly for the ship engine exhaust aftertreatment system provided by the embodiment has the advantages of reasonable design, compact structure and convenience in installation, is beneficial to crushing and evaporating urea solution spray, improves the uniformity of the inlet end face of the catalyst carrier of the reducing agent, and can keep lower back pressure of a mixing section.
Although the invention has been described in detail above with reference to a general description and specific examples, it will be apparent to one skilled in the art that modifications or improvements may be made thereto based on the invention. Accordingly, such modifications and improvements are intended to be within the scope of the invention as claimed.

Claims (10)

1. A mixer assembly for a marine engine exhaust aftertreatment system, the mixer assembly comprising a first exhaust pipe, a second exhaust pipe, a nozzle, a primary mixer, and a secondary mixer;
a nozzle is arranged on the side wall of the front end of the first exhaust pipe, a second exhaust pipe is arranged at the rear end of the first exhaust pipe, and urea solution is atomized by the nozzle and then sprayed into the first exhaust pipe to be mixed with tail gas, and then enters the second exhaust pipe;
a first-stage mixer and a second-stage mixer are sequentially arranged in the second exhaust pipe from the front end to the rear end, and the first-stage mixer is used for guiding the fluid in the second exhaust pipe to the periphery of the inner wall of the second exhaust pipe; the secondary mixer is used to direct the advancing fluid into a rotational motion.
2. The mixer assembly for a marine engine exhaust aftertreatment system of claim 1 wherein the primary mixer includes a set of first fins including a first stationary bracket and first guide vanes; the first fixing support is arranged along the radial direction of the second exhaust pipe, and two ends of the first fixing blade are respectively fixed on the inner wall of the second exhaust pipe; the two first guide vanes are respectively fixed on two sides of the first fixing support and extend towards the inner wall of the second exhaust pipe, an included angle is formed between each first guide vane and the first fixing support, and the two first guide vanes guide fluid in the second exhaust pipe to the periphery of the inner wall of the second exhaust pipe;
or the first-stage mixer comprises a plurality of groups of first fins, each group of first fins comprises a first fixed support and first guide vanes, the first fixed supports are arranged along the radial direction of the second exhaust pipe, two ends of each first fixed vane are respectively fixed on the inner wall of the second exhaust pipe, and the first fixed supports are fixedly arranged along the axis of the second exhaust pipe in a crossed manner; every two ends of the first fixing support are respectively fixed with two first guide vanes extending towards the inner wall of the second exhaust pipe, the two first guide vanes are respectively positioned on two sides of the first fixing support and form included angles with the first fixing support, and the first guide vanes guide fluid in the second exhaust pipe to the periphery of the inner wall of the second exhaust pipe.
3. The mixer assembly for a marine engine exhaust aftertreatment system of claim 2 wherein the primary mixer includes four sets of first fins or six sets of first fins.
4. The mixer assembly for a marine exhaust aftertreatment system according to claim 2 wherein said first guide vane is provided with a plurality of openings;
or the outer surface of the first guide vane is provided with a drainage groove.
5. The mixer assembly for a marine engine exhaust aftertreatment system according to claim 2 wherein the first guide vane is angled from the first mounting bracket by between 30 ° and 60 ° and the length of the end of the first guide vane adjacent the first mounting bracket is greater than the length of the end of the first guide vane distal the first mounting bracket.
6. The mixer assembly for a marine exhaust aftertreatment system of claim 1 wherein said secondary mixer includes a plurality of second guide vanes, each of said plurality of second guide vanes being fixed to an inner wall of a second exhaust pipe and extending toward an axis of said second exhaust pipe, said plurality of second guide vanes being circumferentially spaced about said inner wall of said second exhaust pipe and being angled with respect to said axis of said second exhaust pipe, said second guide vanes guiding the forward moving fluid in a rotational motion.
7. The mixer assembly for a marine exhaust aftertreatment system according to claim 6 wherein the second guide vane is angled from 30 ° to 60 ° relative to the axis of the second exhaust pipe.
8. The mixer assembly for a marine vessel engine exhaust aftertreatment system of claim 6 wherein said secondary mixer further comprises a plurality of second mounting brackets, said plurality of second mounting brackets being disposed in one-to-one correspondence with a plurality of second guide vanes, each of said second guide vanes being secured to an inner wall of said second exhaust pipe by a corresponding said second mounting bracket.
9. The mixer assembly for a marine exhaust aftertreatment system of claim 8 wherein said second mounting bracket is welded to an inner wall of said second exhaust pipe.
10. The mixer assembly for a marine engine exhaust aftertreatment system of claim 1 wherein a gap is provided between the primary mixer and the secondary mixer.
CN201911259735.5A 2019-12-10 2019-12-10 Mixer assembly for a ship's aircraft exhaust aftertreatment system Pending CN110953045A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201911259735.5A CN110953045A (en) 2019-12-10 2019-12-10 Mixer assembly for a ship's aircraft exhaust aftertreatment system

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Application Number Priority Date Filing Date Title
CN201911259735.5A CN110953045A (en) 2019-12-10 2019-12-10 Mixer assembly for a ship's aircraft exhaust aftertreatment system

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112523843A (en) * 2020-11-17 2021-03-19 江苏大学 Control device and method for actively regulating and controlling working environment of diesel engine SDPF system
CN112814767A (en) * 2020-12-31 2021-05-18 保定市屹马汽车配件制造有限公司 Ammonia mixer of automobile exhaust system

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112523843A (en) * 2020-11-17 2021-03-19 江苏大学 Control device and method for actively regulating and controlling working environment of diesel engine SDPF system
CN112523843B (en) * 2020-11-17 2022-03-22 江苏大学 Control device and method for actively regulating and controlling working environment of diesel engine SDPF system
CN112814767A (en) * 2020-12-31 2021-05-18 保定市屹马汽车配件制造有限公司 Ammonia mixer of automobile exhaust system
CN112814767B (en) * 2020-12-31 2022-05-10 保定市屹马汽车配件制造有限公司 Ammonia mixer of automobile exhaust system

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