WO2020019463A1 - 一种应用于尾气处理的扰流结构以及复合式scr混合器 - Google Patents

一种应用于尾气处理的扰流结构以及复合式scr混合器 Download PDF

Info

Publication number
WO2020019463A1
WO2020019463A1 PCT/CN2018/106921 CN2018106921W WO2020019463A1 WO 2020019463 A1 WO2020019463 A1 WO 2020019463A1 CN 2018106921 W CN2018106921 W CN 2018106921W WO 2020019463 A1 WO2020019463 A1 WO 2020019463A1
Authority
WO
WIPO (PCT)
Prior art keywords
spoiler
peripheral wall
spoiler structure
wall
gas treatment
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2018/106921
Other languages
English (en)
French (fr)
Inventor
张超锋
孙川
候晓澄
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.)
Jiangnan University
Original Assignee
Jiangnan University
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Jiangnan University filed Critical Jiangnan University
Publication of WO2020019463A1 publication Critical patent/WO2020019463A1/zh
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust 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
    • F01N3/18—Exhaust 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
    • F01N3/20—Exhaust 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
    • F01N3/206—Adding periodically or continuously substances to exhaust gases for promoting purification, e.g. catalytic material in liquid form, NOx reducing agents
    • F01N3/2066—Selective catalytic reduction [SCR]
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01N—GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR MACHINES OR ENGINES IN GENERAL; GAS-FLOW SILENCERS OR EXHAUST APPARATUS FOR INTERNAL-COMBUSTION ENGINES
    • F01N3/00—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust
    • F01N3/08—Exhaust or silencing apparatus having means for purifying, rendering innocuous, or otherwise treating exhaust for rendering innocuous
    • F01N3/10—Exhaust 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
    • F01N3/24—Exhaust 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
    • F01N3/28—Construction of catalytic reactors
    • F01N3/2892—Exhaust flow directors or the like, e.g. upstream of catalytic device
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00—Road transport of goods or passengers
    • Y02T10/10—Internal combustion engine [ICE] based vehicles
    • Y02T10/12—Improving ICE efficiencies

Definitions

  • the invention relates to the technical field of exhaust aftertreatment of diesel engines, in particular to a spoiler structure and a composite SCR mixer applied to exhaust gas treatment.
  • the mixer can fully mix the vapor phase and the liquid phase, accelerate the pyrolysis of the urea aqueous solution, thereby improving the conversion efficiency of the catalyst and reducing the risk of crystallization on the wall.
  • the indicators for measuring the mixer mainly include: carrier velocity uniformity, ammonia uniformity, back pressure loss and anti-crystallization performance under low temperature operation of the engine.
  • the static mixing unit fixed in the pipe is used to change the flow state of the exhaust gas, so that the fluid is in the pipeline. The flow impacts various types of plate elements, thereby breaking the spray droplets.
  • Existing mixers are divided into two categories: grid baffle structure and spiral leaf structure.
  • the grid baffle structure mixer uses grid-shaped blades staggered up and down as a mixing unit, and the inclination angle of each blade is generally 45 degrees.
  • Rotary blade structure mixers usually use several blades with a certain angle with the horizontal plane, which are divided into single-layer arrangement type and double-layer arrangement type.
  • the former mixer structure can get better velocity uniformity of the front end of the carrier, but the ammonia uniformity is relatively low, and the latter is just the opposite.
  • the grid baffle structure can effectively prevent the formation of block crystals in the middle of the mixer, while the rotary leaf structure mixer can effectively suppress the formation of crystals on the tube wall of the catalyst.
  • the object of the present invention is to provide a spoiler structure and a compound SCR mixer for tail gas treatment, and the rotary blade of the second spoiler can effectively increase the gas flow velocity near the tube wall and improve the component homogenization effect.
  • the temperature of the pipe wall is increased to reduce the risk of crystal formation on the pipe wall; and the grids and baffles of the first spoiler are densely arranged, which can improve the uniformity of the speed of the airflow; the structure of each part of the first spoiler and the second spoiler
  • the functions can be mutually promoted to achieve the effect of maximizing the functions of the hybrid accessories in a limited space.
  • a spoiler structure applied to exhaust gas treatment includes a first spoiler, including a grille, a baffle, and a first peripheral wall;
  • the baffle is disposed on the grille, and the first peripheral wall is disposed on the periphery of the grille;
  • a second spoiler the second spoiler includes a rotary blade and a second peripheral wall, The second peripheral wall is disposed on the periphery of the first peripheral wall, and the spiral leaf is interposed between the second peripheral wall and the first peripheral wall.
  • the grid includes a horizontal substrate and a vertical substrate, and the horizontal substrate and the vertical substrate are intersected.
  • the plane N formed by the horizontal substrate and the vertical substrate is arranged at a certain angle with the baffle.
  • the baffle is divided into a first facing body and a second facing body, and the first facing body and The second facing bodies are arranged adjacently, and the adjacent first facing bodies and the second facing bodies are staggered in opposite directions.
  • the first facing body and the second facing body are both disposed on the vertical substrate.
  • the first peripheral wall and the second peripheral wall are both annular structures.
  • the spiral blade includes a first end surface, a second end surface, a third end surface, and a fourth end surface.
  • the first end face, the second end face, the third end face, and the fourth end face are connected end to end in sequence;
  • the second end surface and the fourth end surface are both arc-shaped structures, and the second end surface is disposed on the periphery of the fourth end surface.
  • connection points of the first end face, the second end face, the third end face, and the fourth end face are sequentially One intersection n, second intersection n, third intersection n and fourth intersection n;
  • first intersection edge n and the second intersection edge n are respectively connected to both ends of the first peripheral wall
  • the third intersection n and the fourth intersection n are respectively connected to both ends of the second peripheral wall.
  • a compound CSR mixer is based on the compound according to claims 1 to 8 Application of spoiler structure
  • the mixer further includes a mixing accessory, and the spoiler structure is disposed in the mixing accessory.
  • the mixing accessories include a carrier and a spraying member, and the spraying member is embedded in and arranged at a certain angle. Inside the carrier
  • the nozzle of the spraying member faces the grille of the spoiler structure.
  • the present invention has reasonable design, compact spoiler structure, and the rotating blades of the second spoiler can effectively increase the gas flow velocity near the tube wall, increase the component homogenization effect, and simultaneously increase the tube wall temperature and reduce the tube.
  • the risk of wall crystal formation; and the dense arrangement of the grille and baffle of the first spoiler can improve the uniformity of the velocity of the airflow; the structural functions of the first spoiler and the second spoiler can promote each other, achieving In the limited space, the effect of the maximum function of the hybrid accessories is exerted; at the same time, under the premise of ensuring high mixing uniformity, the back pressure loss is the lowest compared to traditional hybrid accessories, which meets the needs of use.
  • FIG. 1 is a schematic structural view of the spoiler structure applied to the exhaust gas treatment of the present invention and the front view of the spoiler structure of the first embodiment of the composite SCR mixer.
  • FIG. 2 is a schematic view of a rear view of a spoiler structure applied to exhaust gas treatment according to the present invention and a spoiler structure according to the first embodiment of the composite SCR mixer.
  • FIG. 3 is a schematic view of a spoiler structure applied to exhaust gas treatment according to the present invention and the structure of a rotary blade according to the first embodiment of the composite SCR mixer.
  • FIG. 4 is a schematic diagram of the structure of a spoiler structure applied to exhaust gas treatment according to the present invention and a compound SCR mixer according to a second embodiment of the compound SCR mixer.
  • FIG. 5 is a spoiler structure applied to exhaust gas treatment according to the present invention and a, b, c, and d of a third embodiment of the composite SCR mixer, which respectively represent four types of grid plate type, baffle type, rotary blade type, and composite type. Schematic diagram of the spoiler structure.
  • FIG. 6 is a velocity field cloud diagram of four spoiler structures a, b, c, and d of the third embodiment of the composite SCR mixer according to the spoiler structure applied to the exhaust gas treatment of the present invention.
  • FIG. 7 is a schematic diagram of the velocity distribution within 10 cm of the front surface of the four spoiler structures a, b, c, and d of the third embodiment of the composite SCR mixer according to the spoiler structure applied to the exhaust gas treatment of the present invention.
  • FIG. 8 is a schematic diagram of the front-end surface velocity distribution cloud diagram of the four spoiler structures a, b, c, and d of the third embodiment of the composite SCR mixer according to the spoiler structure applied to the exhaust gas treatment of the present invention.
  • FIG. 9 is a schematic diagram of the ammonia distribution within 10 cm of the front end surface of the four spoiler structures a, b, c, and d of the third embodiment of the composite SCR mixer according to the spoiler structure applied to the exhaust gas treatment of the present invention.
  • FIG. 10 is a schematic diagram of an ammonia distribution cloud at the front end surface of the four spoiler structures a, b, c, and d of the third embodiment of the composite SCR mixer according to the spoiler structure applied to the exhaust gas treatment of the present invention.
  • FIG. 11 is a schematic diagram of the liquid film temperature distribution of the agitator structure of four types of agitator structure a, b, c, and d of the composite SCR mixer according to the third embodiment of the present invention applied to exhaust gas treatment.
  • FIG. 12 is a liquid film thickness distribution diagram of a turbulent structure applied to exhaust gas treatment according to the present invention, and a, b, c, and d four turbulent structure mixers of the third embodiment of the composite SCR mixer.
  • FIG. 13 is a schematic diagram of a radial temperature distribution downstream of the four spoiler structures a, b, c, and d of the third embodiment of the composite SCR mixer according to the spoiler structure applied to the exhaust gas treatment of the present invention.
  • FIG. 14 is a spoiler structure applied to exhaust gas treatment according to the present invention, and a, b, c, and d four types of spoiler structures of the third embodiment of the composite SCR mixer. Distribution diagram.
  • FIG. 15 is a turbulent structure applied to the exhaust gas treatment of the present invention and a liquid film distribution diagram on the side of the tube wall of the four turbulent structures a, b, c, and d of the third embodiment of the composite SCR mixer.
  • FIG. 16 is a liquid film distribution diagram of the bottom surface of the tube wall of the four types of spoiler structures a, b, c, and d of the third embodiment of the composite SCR mixer according to the spoiler structure applied to the exhaust gas treatment of the present invention.
  • FIG. 17 is a schematic view of the turbulent structure applied to the exhaust gas treatment of the present invention and the distribution of crystals upstream of the four turbulent structure a, b, c, and d mixers of the third embodiment of the composite SCR mixer.
  • FIG. 18 is a schematic view of a crystalline structure downstream of four turbulent structures a, b, c, and d of the third embodiment of the composite SCR mixer according to the turbulent structure applied to the exhaust gas treatment of the present invention.
  • FIG. 19 is a schematic diagram showing the weighing quality of the four spoiler structures a, b, c, and d of the third embodiment of the compound SCR mixer according to the present invention, which is used for exhaust gas treatment.
  • FIG. 20 is a schematic diagram of the spoiler structure applied to the exhaust gas treatment of the present invention and the pressure loss of the four spoiler structures a, b, c, and d of the third embodiment of the composite SCR mixer.
  • an embodiment or “an embodiment” referred to herein refers to a particular feature, structure, or characteristic that can be included in at least one implementation of the present invention.
  • the appearances of "in one embodiment” in various places in this specification do not all refer to the same embodiment, nor are they separate or selectively mutually exclusive embodiments.
  • a first embodiment of the present invention provides a turbulent structure applied to exhaust gas treatment and a schematic diagram of the overall structure of a composite SCR mixer.
  • a turbulence applied to exhaust gas treatment is provided.
  • the flow structure and the composite SCR mixer include a spoiler structure 100 including a first spoiler 101 including a grille 101a, a baffle 101b, and a first peripheral wall 101c.
  • the baffle 101b is provided on the grille 101a, and the first periphery
  • the wall 101c is provided on the periphery of the grille 101a; and, the second spoiler 102 includes a spiral blade 102a and a second peripheral wall 102b, and the second peripheral wall 102b is provided on the periphery of the first peripheral wall 101c.
  • the rotary blade 102a is interposed between the second peripheral wall 102b and the first peripheral wall 101c.
  • the main structure of the present invention includes a spoiler structure applied to exhaust gas treatment.
  • the spoiler structure 100 includes a first spoiler 101 and a second spoiler 102.
  • the structural functions of the two components can promote each other to achieve In the limited space, the effect of the maximum function of the mixing accessories is exerted.
  • the back pressure loss is the lowest compared to traditional mixing accessories.
  • the first spoiler 101 includes the grille 101a.
  • the baffle 101b and the first peripheral wall 101c cooperate with each other, so that under forced convection, vortex diffusion and molecular diffusion are achieved, so that the gas and liquid phases are fully mixed, and the speed and the uniformity of ammonia distribution are simultaneously improved.
  • the baffle 101b is disposed on the grille 101a, and the first peripheral wall 101c is wrapped around the periphery of the grille 101a.
  • the grille 101a, the baffle 101b, and the first peripheral wall 101c are integrated structures.
  • the second spoiler 102 divides the airflow into a large-scale vortex, so that the airflow is rotated near the wall surface of the bearing member 201 to generate a vortex, which promotes mass transfer at the bearing member, and includes a rotating blade 102a and a second periphery.
  • the second peripheral wall 102b is disposed on the periphery of the first peripheral wall 101c, and the two are connected by the rotary blade 102a, so the rotary blade 102a is interposed between the second peripheral wall 102b and the first peripheral wall 101c, and the rotary blade 102a is generated
  • the near-wall surface swirls which creates a surface coupling effect with the middle airflow, improves the wall heat distribution, reduces the risk of liquid film accumulation at the pipe wall, and can effectively reduce the probability of crystal formation.
  • the first spoiler 101 and the second The spoiler 102 is an integrated structure and is made of cast iron or stainless steel.
  • the grid 101a includes a horizontal substrate 101a-1 and a vertical substrate 101a-2, and the horizontal substrate 101a-1 and the vertical substrate 101a-2 are intersected, wherein the number of the horizontal substrate 101a-1 and the vertical substrate 101a-2 is at least There are two (the number in the figure is for reference only), where the plane N formed by the horizontal substrate 101a-1 and the vertical substrate 101a-2 and the baffle 101b are arranged at a certain angle, and the angle and Yes, in this embodiment, the plane N formed by the horizontal substrate 101a-1 and the vertical substrate 101a-2 is arranged at an angle of 45 ° with the baffle plate 101b; and the horizontal substrate 101a-1 and the vertical substrate 101a-2 are perpendicular to each other. Settings.
  • the baffle 101b is divided into a first facing body 101b-1 and a second facing body 101b-2, and the first facing body 101b-1 and the second facing body 101b-2 are disposed adjacent to each other, and adjacent to the first facing body 101b-1 and second orientation body 101b-2 are staggered in reverse, which can create turbulence on the exhaust gas and promote rapid pyrolysis of droplets.
  • the first orientation body 101b-1 and the second orientation body 101b-2 Both are trapezoidal structures; it should be noted that the first facing body 101b-1 and the second facing body 101b-2 are both disposed on the vertical substrate 101a-2.
  • first peripheral wall 101c and the second peripheral wall 102b are both annular structures, and the two are concentric rings; the first peripheral wall 101c is disposed inside the second peripheral wall 102b.
  • the rotary blade 102a includes a first end surface 102a-1 and a second end surface 102a.
  • Both the second end surface 102a-2 and the fourth end surface 102a-4 are arc-shaped structures, and the second end surface 102a-2 is disposed on the periphery of the fourth end surface 102a-4; it should be noted that the first end surface 102a-1, the second end surface The junctions of the end faces 102a-2, the third end face 102a-3, and the fourth end face 102a-4 are, in order, the first intersection n1, the second intersection n2, the third intersection n3, and the fourth intersection n4; A cross edge n1 and a second cross edge n2 are connected to both ends of the first peripheral wall 101c; wherein a third cross edge n3 and a fourth cross edge n4 are connected to both ends of the second
  • a second embodiment of the present invention is different from the first embodiment in that the composite SCR mixer includes a spoiler structure 100, and further includes a mixing accessory 200, a spoiler structure 100 and a hybrid
  • the fittings 200 cooperate with each other to achieve the maximum function of the mixed fittings 200 in a limited space and the process of discharging.
  • the back pressure loss is the lowest compared to the traditional mixing fittings 200, which meets Usage requirements.
  • the main structure includes a spoiler structure 100 including a first spoiler 101 and a second spoiler 102, and the structural functions of the two components can promote each other to achieve the maximum performance of the hybrid accessories in a limited space.
  • the first spoiler 101 includes a grille 101a, a baffle 101b, and a first periphery.
  • the wall 101c and the three cooperate with each other, so that they can be fully mixed by the vortex diffusion and molecular diffusion under forced convection, and the purpose of simultaneously improving the speed and the uniformity of ammonia distribution is achieved.
  • the baffle 101b It is arranged on the grille 101a, and the first peripheral wall 101c is wrapped around the periphery of the grille 101a.
  • the grille 101a, the baffle 101b, and the first peripheral wall 101c are an integrated structure; the second spoiler 102,
  • the airflow is divided into large-scale vortices, so that the airflow rotating near the wall surface of the carrier 201 generates vortices, which promotes mass transfer at the carrier, and includes a rotating blade 102a and a second peripheral wall 102b.
  • the second peripheral wall 102b is provided at The periphery of a peripheral wall 101c, the two are connected by a rotating blade 102a, so the rotating blade 102a is located between the second peripheral wall 102b and the first peripheral wall 101c.
  • the near-wall surface swirl generated by the spiral blade 102a and the middle airflow Generate surface coupling effect, improve the wall heat distribution, reduce the risk of liquid film accumulation at the wall of the tube, and effectively reduce the probability of crystal formation.
  • the first spoiler 101 and the second spoiler 102 are integrated structures. Made of cast iron or stainless steel.
  • the composite SCR mixer also includes a mixing part 200.
  • the mixing part 200 includes a carrier 201 and a sprinkler 202.
  • the sprinkler 202 is embedded in the carrier 201 by welding at a certain angle, and the spoiler structure 100 is disposed in the carrier 201
  • the two can be made by bolts or welding.
  • the spraying part 202 uses a three-hole nozzle
  • the carrier 201 is a cylindrical shell and is made of cast iron
  • the nozzle of the spraying part 202 faces the turbulence in the same direction as the exhaust gas flow direction.
  • the grille 101a of the structure 100 provides such a better mixing.
  • both ends of the bearing member 201 are provided with a first connection flange 201a and a second connection flange 201b.
  • the first connection flange 201a is connected to the exhaust exhaust pipe by a bolt
  • the second connection flange 201b is connected to the exhaust pipe by a bolt. Exhaust gas inlet pipe connection.
  • the flow structure 100 is a composite structure.
  • the spoiler structure 100 is installed in a suitable mixing fitting 200, which can make the composite SCR mixer significantly improve the flow field distribution, make the vapor phase meet the liquid phase to be fully mixed, and accelerate the pyrolysis of the urea aqueous solution, thereby improving the composite SCR mixing.
  • the conversion efficiency of the device reduces the risk of crystallization on the wall surface of the carrier 201.
  • the indicators for measuring the compound SCR mixer mainly include: carrier velocity uniformity, ammonia uniformity, back pressure loss and anti-crystallization performance under low temperature operation of the engine.
  • the mixing process generally uses a static mixing unit fixed in the carrier tube to change the flow state of the exhaust gas, so that the fluid flows in the pipeline to impact various types of plate elements, so that the spray droplets are completely broken.
  • (A) of FIG. 5 is a grid plate type spoiler structure, in which each baffle unit is at an angle of 45 ° to the horizontal plane, and 6 rows and 7 rows are staggered.
  • the dead corners of crystals may be generated at the reverse staggering of the blades, and improve the heat transfer efficiency on the wall surface;
  • the large plate structure at 70 ° to the horizontal plane, with the outer blades facing down and the middle part facing up, can create turbulence for the exhaust gas division, and promote rapid pyrolysis of the droplets.
  • the spoiler structure is designed as a double-layered spiral blade structure (Figure 5 (c)), which constitutes a spiral-blade-type spoiler structure.
  • each layer consists of 9 blades. Structure, the first layer is arranged counterclockwise, and the second layer is arranged counterclockwise; the droplets first hit the wall surface of the spoiler structure to complete the crushing, and then the swirl created by the blade is fully mixed with the exhaust gas, so that the droplets quickly Pyrolysis.
  • the traditional spoiler structure usually does not consider the crystallization of the wall surface. Therefore, based on the traditional grid plate spoiler structure (Figure 5 (a)), 8 blades with inclined angles are designed on the outside of the grid plate ( Figure 5 (d) )), Which constitutes the preferred composite spoiler structure, which generates swirling near-wall surface through these blades, and generates a coupling effect with the middle airflow, thereby improving the uniformity of airflow while improving the heat distribution on the wall.
  • the test bench mainly includes a VM28 (97KW) diesel engine (such as Table 1), an SCR aftertreatment system, an electric dynamometer and its control system, a fuel supply and fuel consumption measurement system, an intercooler, and a multi-component gas analyzer.
  • VM28 97KW diesel engine
  • the above-mentioned four spoiler components are respectively welded to the flange, and then installed at a distance of 10 cm from the rear end of the spray member 202.
  • ESC European Steady-State Cycle
  • ETC European Unsteady-State Cycle
  • the uneven flow velocity distribution for a long time will cause excessive air velocity and temperature at the higher flow velocity of the carrier, which will cause the radial temperature gradient of the catalyst to be too large, which will generate thermal stress gradients, cause thermal fatigue damage, accelerate the catalyst's degradation and reduce its Service life.
  • the uneven distribution of reducing agent will cause local excessive or insufficient ammonia distribution, resulting in reduced SCR catalytic efficiency and ammonia gas leakage, uneven catalyst aging, and affecting the overall catalytic performance.
  • the performance of the rate must make the UWS distributed as evenly as possible on the front surface of the carrier. Its uniformity coefficient is expressed as follows:
  • Vi is the normal velocity of the unit carrier
  • Vmean is the normal average velocity of the end face of the carrier air inlet
  • A is the cross-sectional area of the unit
  • Ai is the total number of interface meshes.
  • the velocity field distribution of the four spoiler structures is shown in Figure 6.
  • the airflow in the middle of the downstream of the inlet pipe with the grid channel plate spoiler structure is relatively smooth.
  • the axial speed in the tube 201 is stable and the uniformity of the speed in the tube is better ( Figure 6 (a)).
  • the velocity uniformity of the UWS in the axial distance in front of the spoiler structure carrier is directly related to the utilization of the catalyst.
  • the velocity uniformity of the axial cross sections in the range of 10 cm in length of the front surface of the carrier under different spoiler structures is shown in Figure 7; the velocity uniformity of Case1 and Case2 at 8 cm in the mixing cavity suddenly decreases, and the lowest values are respectively 0.64 and 0.72; the overall velocity uniformity is significantly lower than Case3 and Case4; although Case3 has the highest uniformity index at 0 to 8 cm away from the carrier, there is also a sudden decrease in velocity uniformity in Case 3 at 9 cm Compared with case1 and case2, the minimum value is increased to 0.79; Case4 is the only test piece that does not show a sudden decrease in velocity uniformity, which makes its uniformity index in the area 10cm in front of the carrier reaches more than 8.3, which significantly improves the velocity distribution in the mixing cavity. Uniformity can effectively eliminate dead angles in low-speed flow areas.
  • the reducing agent uniformity index in the mixing chamber is an important index to measure whether the mixer can continuously obtain the maximum denitration rate and the minimum ammonia leakage.
  • Figure 9 shows the uniform exponential distribution of ammonia in the axial section at 10 cm in front of the carrier when different spoiler structures are loaded.
  • the plate-like blade spoiler structure of case1 and case2 can produce axially stable laminar flow, but it cannot overcome the disturbance of the airflow by the mixing plate, which leads to a significant exponential drop near the mixing plate at 8cm in both scenarios. Zone, ammonia uniformity is lowest at 0.53 and 0.57.
  • case3 and case4 spoiler structure with spiral blade structure effectively eliminates the sudden decrease in the ammonia uniformity index caused by the mixing plate by manufacturing a circumferential rotating airflow, and at the same time ensures that the axial ammonia concentration distribution index in the mixing chamber is always Keep above 0.75, which is nearly 1.5 times that of case1 and case2.
  • Table 2 reflects the velocity uniformity and ammonia uniformity index at 1 cm inside the carrier. From the table we can see that traditional case1 has advantages in speed uniformity, while case3 has advantages in ammonia uniformity.
  • the new composite spoiler structure designed in this paper not only combines the advantages of case1 and case3, but also improves the speed uniformity and ammonia uniformity to 0.993 and 0.924, respectively.
  • For component homogenization and mass transfer when the exhaust gas enters the intake pipe, the airflow passing through the outer blades of the spoiler structure is divided into large-scale vortices, so that the near-surface airflow rotates to generate vortices, which promotes mass transfer at the pipe wall.
  • the swirling flow at the wall of the tube drives the airflow stretched and sheared through the middle grid baffle to rotate, so that it can diffuse through the vortex and molecular diffusion under the force of convection, thereby achieving the purpose of sufficient mixing of gas and liquid phases.
  • the purpose of simultaneously improving the speed and the uniformity of ammonia distribution is achieved.
  • the temperature of the wall film is the main factor that determines the chemical properties of the relevant sediments.
  • the temperature of the wall film is between about 160 ° C and 170 ° C. Once crystals are formed in low temperature conditions, not only will the exhaust pipe be blocked and the back pressure will be increased, but the flow field distribution will be changed and the working efficiency of the mixer will be reduced.
  • the liquid film temperature distribution of the spoiler structure is shown in Figure 11.
  • case1 there is a large area of low temperature in the lower part of the blade (T ⁇ 133 °C), and the maximum temperature difference of the liquid film of the spoiler structure is 102 ⁇ 110 °C ( Figure 11 (a)).
  • case2 there is a low temperature region (T ⁇ 155 ° C) at the third and third row of baffles ( Figure 11 (b)).
  • the temperature distribution of the other baffles is uniform and the temperature is mostly above 200 ° C. It can be seen that the large blade structure can be used. Improve the temperature of the liquid film on the wall to a certain extent.
  • the spiral leaf-like spoiler structure case3 is located at the tip of the blade where the nozzle is directly sprayed and there is an obvious low-temperature liquid film aggregation area at the second layer of spiral leaves (Figure 11 (c)).
  • the temperature distribution of case4 is better than the other three schemes.
  • the grid plate area in the middle of the spoiler structure is evenly heated.
  • the low temperature area is mainly distributed on the three blades at the junction of the spoiler structure and the bottom of the pipe wall ( Figure 11 (d)). There may be liquid film deposition on the leaves.
  • the liquid film temperature determines the liquid film thickness distribution of the spoiler structure and the location of the sediment to a certain extent.
  • the probability of liquid film accumulation in regions with a temperature below 156 ° C is significantly higher than in other parts.
  • Figure 13 shows the radial temperature distribution in the downstream direction of the turbulent structure perpendicular to the tube wall (tube wall diameter 8cm).
  • the abscissa axis 0 is the upper edge near the nozzle
  • 8 is the contact portion between the lower edge and the bottom of the tube wall
  • the right end is the disturbance.
  • the flow structure contacts the pipe wall. It can be observed from the figure that when the spray particles first came into contact with the wall of the spoiler structure, the temperature of the upper area of case1 was 172 ° C, which was about 30 ° C lower than the other three types, and the difference in the temperature distribution of the grid plate was small. A significant temperature decrease was observed at 6cm in the middle and lower part of case2.
  • FIG 14 shows the temperature distribution at the axial 14cm downstream of the contact point between the spoiler structure and the bottom of the wall.
  • the left end of the abscissa axis is the contact point between the spoiler structure and the pipe wall, and the right end is 14cm away from this point.
  • the temperature range of case1 is 195 ⁇ 207 °C, the fluctuation range is small, and the temperature distribution is ideal.
  • the average temperature of the wall area of case2 is the lowest of the four schemes, and there is a continuous low temperature region at 6-9cm, and the lowest temperature is reduced to 153 ° C, which is relatively easy to form crystals.
  • Case3 Although the wall temperature of Case3 decreased significantly at 5-9 cm, the overall temperature range was 174-214 ° C, and the lowest value was still higher than the high sediment formation risk temperature (T ⁇ 170 ° C).
  • T ⁇ 170 ° C The temperature distribution of Case4 ranges from 189 to 211 ° C, and the overall temperature is maintained at a relatively high level.
  • the heat transfer effect of the composite spoiler structure on the downstream pipe wall is significantly better than that of case2 and case3.
  • Case2 has a small area of liquid film deposition along the circumference of the tube wall ( Figure 15 (a)), and most of the sediment is concentrated at the bottom of the tube wall ( Figure 16 (a)). This part has a great risk of crystallization.
  • the deposition area of case3 is mainly concentrated in the circumferential area ( Figure 15 (c)) where the spoiler structure contacts the bottom of the tube wall, and no obvious liquid film aggregation area is observed at the bottom of the wall ( Figure 16 (c)).
  • Case3 spiral-blade spoiler structure produces severe crystallization at the blade interlayer.
  • Figure 17 (c) The formation of massive crystals is due to the larger liquid film area of the blade under the spoiler structure.
  • Figure 12 (c) resulting in accumulation effects.
  • the uneven heating of the blades at the bottom of the spoiler structure can't make the reducing agent pyrolyze quickly.
  • Case4 has the least crystals on the composite spoiler structure, and the amount of crystals at the tube wall is significantly lower than that of case1. This is mainly because the outer blades make the airflow rotate to increase the airflow velocity near the wall, which improves the heat and mass transfer at the wall. The situation makes the liquid film hard to accumulate here, and effectively reduces the risk of crystallization on the wall surface.
  • the spoiler structure only has a small amount of crystals attached in the middle and lower part of the grid baffle, the amount of crystals is significantly less than that of case 1, and no block crystals are generated to block the pipeline.
  • Figure 17 (d) This is because the outer swirling flow causes the airflow at the central grid plate to move in a circumferential direction, reducing the residence time of the droplets on the wall surface, and effectively reducing the risk of forming a liquid film deposition area.
  • the parts loaded with the four spoiler structures were disassembled and weighed, as shown in Figure 19, and the weight of the sediment was obtained by comparing the weight difference of the system before and after the experiment (the measurement accuracy is ⁇ 0.01 g). It is found from the figure that the crystal weight of the spoiler structure gradually increases from case1 to case3, and the minimum crystal weight of case4 is 2.31g, which are respectively 34.7%, 22.6%, and 16.7% of case1, case2, and case3.
  • the experimental data show that although the double-layer spiral leaf structure can obtain better ammonia uniformity, it is very easy to form large crystals at low temperature conditions.
  • the spoiler structure with a grid channel plate can effectively improve the structure. Crystallization performance of the mixer under low temperature conditions.
  • FIG 20 shows the back pressure loss of the four spoiler structures. It can be seen from the figure that the back pressure loss of the case 4 composite spoiler structure is similar to the back pressure loss of case 1, but the ammonia uniformity of the former is 6.7% higher than that of the latter. . At the same time, when the ammonia uniformity of case4 and case3 is close, the pressure loss of the former is effectively reduced by 139Pa compared with the latter. In summary, the spoiler structure of case 4 has better comprehensive performance.
  • this study proposes a new composite spoiler structure in combination with the existing spoiler structure.
  • the new spoiler structure significantly reduces the amount of crystals under low temperature conditions, which significantly improves the mixer's resistance to crystal formation under low temperature conditions.
  • the ammonia uniformity index is increased by 6.7%, 3.1%, and 0.07% compared to case1, case2, and case3, respectively. Moreover, in the case of obtaining the same ammonia uniformity (compared to case 3), the exhaust back pressure is reduced by 7.8%.
  • the installation of a rotating blade structure on the spoiler structure can effectively increase the gas flow velocity near the tube wall, improve the component homogenization effect, increase the tube wall temperature, and reduce the risk of crystal formation on the tube wall.
  • the dense grid baffle structure can improve the velocity uniformity of the airflow.

Landscapes

  • 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

一种应用于尾气处理的扰流结构以及复合式SCR混合器，所述扰流结构（100）包括，第一扰流件（101），包括格栅（101a）、挡板（101b）和第一外围壁（101c），所述挡板（101b）设置于所述格栅（101a）上，所述第一外围壁（101c）设置于所述格栅（101a）的外围；以及，第二扰流件（102），所述第二扰流件（102）包括旋叶（102a）和第二外围壁（102b），所述第二外围壁（102b）设置于第一外围壁（101c）的外围，所述旋叶（102a）介于所述述第二外围壁（102b）和第一外围壁（101c）之间。该扰流结构结构紧凑，第二扰流件（102）的旋叶（102a）可有效增加气体在近管壁处流速提高组份均化效果，同时提升管壁温度，降低管壁结晶物形成风险；而第一扰流件（101）的格栅（101a）和挡板（101b）密集设置，可以提高气流的速度均匀性。

Description

一种应用于尾气处理的扰流结构以及复合式SCR混合器 技术领域
本发明涉及的柴油发动机排气后处理技术领域，尤其涉及一种应用于尾气处理的扰流结构以及复合式SCR混合器。
背景技术
以往的研究结果表明，SCR混合器中安装合适的混合器可以显著改善流场分布。混合器可以使汽相遇液相充分混合，加速尿素水溶液热解，从而提高催化器的转化效率，减小壁面结晶风险。衡量混合器的指标主要包括：载体速度均匀性、氨均匀性、背压损失与发动机低温运行下抗结晶性能混合过程一般利用固定在管内的静态混合单元改变废气的流动状态，使流体在管线中流动冲击各种类型板元件，从而使喷雾液滴完成破碎。已有的混合器分为网格挡板结构和旋叶结构两大类。
网格挡板结构混合器采用上下交错排布呈网格状叶片作为混合单元，各叶片倾斜角度一般为45度。旋叶结构混合器通常采用与水平面有一定夹角的若干叶片，分为单层排布型和双层排布型。前者混合器结构可获得较好的载体前端面速度均匀性，但是氨均匀性相对较低，后者则刚好相反。在抗结晶性能方面，网格挡板式结构可有效防止混合器中部产生块状结晶物，而旋叶结构混合器则能有效抑制催化器管壁结晶物的生成。
发明内容
本部分的目的在于概述本发明的实施例的一些方面以及简要介绍一些较佳实施例。在本部分以及本申请的说明书摘要和发明名称中可能会做些简化或省略以避免使本部分、说明书摘要和发明名称的目的模糊，而这种简化或省略不能用于限制本发明的范围。
鉴于上述现有应用于尾气处理的扰流结构以及复合式SCR混合器存在的问题，提出了本发明。
因此，本发明目的是提供一种应用于尾气处理的扰流结构以及复合式SCR混合器，其第二扰流件的旋叶可有效增加气体在近管壁处流速提高组份均化效果，同时提升管壁温度，降低管壁结晶物形成风险；而第一扰流件的格栅和挡板密集设置，可以提高气流的速度均匀性；第一扰流件和第二扰流件各部结构功能可相互促进，达到了在有限空间内发挥混合配件最大功能的效果。
为解决上述技术问题，本发明提供如下技术方案：一种应用于尾气处理的扰流结构，所述扰流结构包括，第一扰流件，包括格栅、挡板和第一外围壁，所述挡板设置于所述格栅上，所述第一外围壁设置于所述格栅的外围；以及，第二扰流件，所述第二扰流件包括旋叶和第二外围壁，所述第二外围壁设置于第一外围壁的外围，所述旋叶介于所述述第二外围壁和第一外围壁之间。
作为本发明所述应用于尾气处理的扰流结构以及复合式SCR混合器的一种优选方案，其中：所述格栅包括横基板和纵基板，所述横基板与纵基板交叉设置。
作为本发明所述应用于尾气处理的扰流结构以及复合式SCR混合器的一种优选方案，其中：所述横基板与纵基板构成的平面N与所述挡板呈一定夹角排布。
作为本发明所述应用于尾气处理的扰流结构以及复合式SCR混合器的一种优选方案，其中：所述挡板区分为第一朝向体和第二朝向体，所述第一朝向体和第二朝向体相邻设置，且相邻的第一朝向体和第二朝向体反向交错设置。
作为本发明所述应用于尾气处理的扰流结构以及复合式SCR混合器的一种优选方案，其中：所述第一朝向体和第二朝向体均设置于所述纵基板上。
作为本发明所述应用于尾气处理的扰流结构以及复合式SCR混合器的一种优选方案，其中：所述第一外围壁和第二外围壁均为圆环结构。
作为本发明所述应用于尾气处理的扰流结构以及复合式SCR混合器的一种优选方案，其中：所述旋叶包括第一端面、第二端面、第三端面和第四端面，所述第一端面、第二端面、第三端面和第四端面首尾依次连接；
其中，所述第二端面与第四端面均为弧形结构，所述第二端面设置于所述第四端面的外围。
作为本发明所述应用于尾气处理的扰流结构以及复合式SCR混合器的一种优选方案，其中：所述第一端面、第二端面、第三端面和第四端面的连接处依次为第一交边n、第二交边n、第三交边n和第四交边n；
其中，所述第一交边n和第二交边n分别与所述第一外围壁的两端边连接；
其中，所述第三交边n和第四交边n分别与所述第二外围壁的两端边连接。
作为本发明所述应用于尾气处理的扰流结构以及复合式SCR混合器的一种优选方案，其中：一种复合式CSR混合器，所述混合器依托于如权利要求 1～8所述的扰流结构应用，
其中，所述混合器还包括混合配件，所述扰流结构设置于所述混合配件内。
作为本发明所述应用于尾气处理的扰流结构以及复合式SCR混合器的一种优选方案，其中：所述混合配件包括承载件和喷洒件，所述喷洒件呈一定角度嵌入设置于所述承载件内；
其中，所述喷洒件的喷口朝向所述扰流结构的格栅。
本发明的有益效果：本发明设计合理，扰流结构结构紧凑，第二扰流件的旋叶可有效增加气体在近管壁处流速提高组份均化效果，同时提升管壁温度，降低管壁结晶物形成风险；而第一扰流件的格栅和挡板密集设置，可以提高气流的速度均匀性；第一扰流件和第二扰流件各部结构功能可相互促进，达到了在有限空间内发挥混合配件最大功能的效果；同时，在保证高混合均匀性的前提下，背压损失相较于传统混合配件最低，满足使用需求。
附图说明
为了更清楚地说明本发明实施例的技术方案，下面将对实施例描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动性的前提下，还可以根据这些附图获得其它的附图。其中：
图1为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第一个实施例的扰流结构正视的结构示意图。
图2为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第一个实施例所述的扰流结构后视结构示意图。
图3为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第一个实施例的所述的旋叶结构示意图。
图4为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第二个实施例复合式SCR混合器结构示意图。
图5为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d分别表示网格板式、挡板式、旋叶式、复合式四种扰流结构示意图。
图6为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构的速度场云图。
图7为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构载体前端面10cm内速度分布示意图。
图8为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构载体前端面速度分布云图示意图。
图9为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构载体前端面10cm内氨分布示意图。
图10为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构载体前端面氨分布云示意图。
图11为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构混合器液膜温度分布示意图。
图12为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构混合器液膜厚度分布图。
图13为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的沿a、b、c、d四种扰流结构下游径向温度分布示意图。
图14为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构混合器与壁面底部接触点下游处轴向14cm温度分布示意图。
图15为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构管壁侧面液膜分布图。
图16为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构管壁底面液膜分布图。
图17为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构混合器上游结晶物分布示意图。
图18为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构下游结晶物分布示意图。
图19为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构结晶物称重质量示意图。
图20为本发明应用于尾气处理的扰流结构以及复合式SCR混合器第三个实施例的a、b、c、d四种扰流结构压力损失示意图。
具体实施方式
为使本发明的上述目的、特征和优点能够更加明显易懂，下面结合说明书附图对本发明的具体实施方式做详细的说明。
在下面的描述中阐述了很多具体细节以便于充分理解本发明，但是本发明还可以采用其他不同于在此描述的其它方式来实施，本领域技术人员可以在不违背本发明内涵的情况下做类似推广，因此本发明不受下面公开的具体实施例的限制。
其次，此处所称的“一个实施例”或“实施例”是指可包含于本发明至少一个实现方式中的特定特征、结构或特性。在本说明书中不同地方出现的“在一个实施例中”并非均指同一个实施例，也不是单独的或选择性的与其他实施例互相排斥的实施例。
再其次，本发明结合示意图进行详细描述，在详述本发明实施例时，为便于说明，表示器件结构的剖面图会不依一般比例作局部放大，而且所述示意图只是示例，其在此不应限制本发明保护的范围。此外，在实际制作中应包含长度、宽度及深度的三维空间尺寸。
参照图1和2，为本发明第一个实施例，提供了一种应用于尾气处理的扰流结构以及复合式SCR混合器的整体结构示意图，如图1，一种应用于尾气处理的扰流结构以及复合式SCR混合器包括扰流结构100包括，第一扰流件101，包括格栅101a、挡板101b和第一外围壁101c，挡板101b设置于格栅101a上，第一外围壁101c设置于格栅101a的外围；以及，第二扰流件102，第二扰流件102包括旋叶102a和第二外围壁102b，第二外围壁102b设置于第一外围壁101c的外围，旋叶102a介于述第二外围壁102b和第一外围壁101c之间。
具体的，本发明主体结构包括一种应用于尾气处理的扰流结构，扰流结构100包括，第一扰流件101和第二扰流件102，两者各部结构功能可相互促进，达到了在有限空间内发挥混合配件最大功能的效果；同时，在保证高混合均匀性的前提下，背压损失相较于传统混合配件最低，需说明的是，第一扰流件101包括格栅101a、挡板101b和第一外围壁101c，三者相互配合，使其在强制对流作用下通过涡流扩散和分子扩散，进而达到气液相充分混合的，实现了同时提高速度和氨分布均匀性的目的，进一步的，挡板101b设置于格栅101a上，而第一外围壁101c包裹于格栅101a的外围，较好的，格栅101a、挡板101b和第一外围壁101c为一体式结构；第二扰流件102，将气流被分割形成大尺度的涡旋， 使得近承载件201壁面气流旋转产生涡流，促进承载件处传质，其包括旋叶102a和第二外围壁102b，第二外围壁102b设置于第一外围壁101c的外围，两者通过旋叶102a连接，故旋叶102a介于述第二外围壁102b和第一外围壁101c之间，旋叶102a产生的近壁面旋流，与中间的气流产生面耦合效应，改善壁热量分布，减少管壁处液膜积聚风险，可有效降低结晶物生成几率，较好的，第一扰流件101和第二扰流件102为一体式结构，采用铸铁或不锈钢材料制成。
进一步的，格栅101a包括横基板101a-1和纵基板101a-2，横基板101a-1与纵基板101a-2交叉设置，其中，横基板101a-1和纵基板101a-2个数均至少设置有2个(图中个数仅作参考)，其中，横基板101a-1与纵基板101a-2构成的平面N与挡板101b呈一定夹角排布，其中夹角与，需说明的是，本实施例图示中，横基板101a-1与纵基板101a-2构成的平面N与挡板101b成45°夹角排布；而横基板101a-1与纵基板101a-2为垂直设置。
进一步的，挡板101b区分为第一朝向体101b-1和第二朝向体101b-2，第一朝向体101b-1和第二朝向体101b-2相邻设置，且相邻第一朝向体101b-1和第二朝向体101b-2反向交错设置，可对废气分割制造湍流，促进液滴迅速热解；其图示中，第一朝向体101b-1和第二朝向体101b-2均为梯形结构；需说明的是，第一朝向体101b-1和第二朝向体101b-2均设置于纵基板101a-2上。
进一步的，第一外围壁101c和第二外围壁102b均为圆环结构，且两者为同心圆环；第一外围壁101c设置于第二外围壁102b的内侧。
进一步的，参照图3，旋叶102a至少设置有2个，2个旋叶102a顺时针排列，(图中个数仅作参考)，旋叶102a包括第一端面102a-1、第二端面102a-2、第三端面102a-3和第四端面102a-4，第一端面102a-1、第二端面102a-2、第三端面102a-3和第四端面102a-4首尾依次连接；其中，第二端面102a-2与第四端面102a-4均为弧形结构，第二端面102a-2设置于第四端面102a-4的外围；需说明的是，第一端面102a-1、第二端面102a-2、第三端面102a-3和第四端面102a-4的连接处依次为第一交边n1、第二交边n2、第三交边n3和第四交边n4；其中，第一交边n1和第二交边n2分别与第一外围壁101c的两端边连接；其中，第三交边n3和第四交边n4分别与第二外围壁102b的两端边连接；具体的，第四交边n4设置于相邻旋叶102a下方，相邻旋叶102a呈局部层叠设置，即整体呈现螺旋状结构。
参照图4，为本发明的第二个实施例，该实施例不同于第一个实施例的是：复合式SCR混合器包括扰流结构100，还包括混合配件200，扰流结构100和混合配件200相互配合，可达到了在有限空间内发挥混合配件200最大功能的效果以及排放的过程；同时，在保证高混合均匀性的前提下，背压损失相较于传统混合配件200最低，满足使用需求。具体的，参见图1，其主体结构包括扰流结构100包括，第一扰流件101和第二扰流件102，两者各部结构功能可相互促进，达到了在有限空间内发挥混合配件最大功能的效果；同时，在保证高混合均匀性的前提下，背压损失相较于传统混合配件最低，需说明的是，第一扰流件101包括格栅101a、挡板101b和第一外围壁101c，三者相互配合，使其在强制对流作用下通过涡流扩散和分子扩散，进而达到气液相充分混合的，实现了同时提高速度和氨分布均匀性的目的，进一步的，挡板101b设置于格栅101a上，而第一外围壁101c包裹于格栅101a的外围，较好的，格栅101a、挡板101b和第一外围壁101c为一体式结构；第二扰流件102，将气流被分割形成大尺度的涡旋，使得近承载件201壁面气流旋转产生涡流，促进承载件处传质，其包括旋叶102a和第二外围壁102b，第二外围壁102b设置于第一外围壁101c的外围，两者通过旋叶102a连接，故旋叶102a介于述第二外围壁102b和第一外围壁101c之间，旋叶102a产生的近壁面旋流，与中间的气流产生面耦合效应，改善壁热量分布，减少管壁处液膜积聚风险，可有效降低结晶物生成几率，较好的，第一扰流件101和第二扰流件102为一体式结构，采用铸铁或不锈钢材料制成。而复合式SCR混合器还包括混合配件200，混合配件200包括承载件201和喷洒件202，喷洒件202呈一定角度通过焊接嵌入设置于承载件201内，扰流结构100设置于承载件201内，两者可通过螺栓或焊接制成，其中，喷洒件202采用三孔喷嘴，承载件201为圆柱型壳体，采用铸铁材料制成，而喷洒件202的喷口同废气流动方向一样朝向扰流结构100的格栅101a，如此更好混合提供了调节。
进一步的，承载件201的两端均设置有第一连接法兰201a和第二连接法兰201b，第一连接法兰201a通过螺栓与尾气排气筒连接，第二连接法兰201b通过螺栓与废气入气管连接。
参照图5～20，为本发明的第三个实施例，该实施例不同于以上实施例的是：通过一系列对比实验来证明本扰流结构100最优性能，需说明的是，本扰流结构100为复合式结构。具体的，扰流结构100安装在合适的混合配件200中，可使 复合式SCR混合器以显著改善流场分布，使汽相遇液相充分混合，加速尿素水溶液热解，从而提高复合式SCR混合器的转化效率，减小承载件201壁面结晶风险。衡量复合式SCR混合器的指标主要包括：载体速度均匀性、氨均匀性、背压损失与发动机低温运行下抗结晶性能。
混合过程一般利用固定在承载件管内的静态混合单元改变废气的流动状态，使流体在管线中流动冲击各种类型板元件，从而使喷雾液滴完成破碎。图5的(a)为网格板式扰流结构，其中各挡板单元与水平面呈45°夹角，采用6列7排交错排布。
为消除(图5(a))网格板式扰流结构叶片反向交错处可能产生结晶的死角，提升壁面传热效率；图5(b)为挡板室式扰流结构，其中采用四排与水平面成70°的大板结构，外侧叶片向下，中部向上，可对废气分割制造湍流，促进液滴迅速热解。
为了使流体进一步混合以达到与雾化颗粒充分混合，将扰流结构设计成双层旋叶结构(图5(c))，构成旋叶式扰流结构，具体的由每层由9个叶片构成，第一层逆时针排布，第二层呈顺时针反向排布；液滴首先撞击扰流结构叶片壁面完成破碎，而后通过叶片制造的旋流充分与废气混合，从而使液滴快速热解。
传统扰流结构结构通常不考虑壁面结晶问题，因此在传统网格板式扰流结构(图5(a))的基础上，在网格板外侧设计了8个带倾角的叶片(图5(d))，即构成了本优选的复合式扰流结构，其通过这些叶片来产生近壁面旋流，与中间的气流产生耦合效应，从而在改善壁面热量分布的同时提高整体的气流均匀性。
对以上四种扰流组件作如下实验以及分析：
试验台架主要包括VM28(97KW)柴油发动机(如表1)、SCR后处理系统、电力测功机及其控制系统、燃油供给及油耗测量系统、中冷器、多组分气体分析仪等。
将上述四种扰流组件分别焊接在法兰上，然后安装在距离喷洒件202后端10cm处。在带尿素喷射的情况下分别进行一遍ESC(欧洲稳态循环)和ETC(欧洲非稳态循环)循环。接着依据结晶规范进行一个循环340s，总时间为20个小时的结晶试验。试验完成后，将扰流组件拆解下来称重并将SCR混合器前端剖 开，查看具体结晶分布情况。
Table1发动机参数
Figure PCTCN2018106921-appb-000001
结果及讨论：
1、均匀性
影响催化剂催化效率的主要因素有两种，一是气体流速均匀性，二是氨蒸汽分布均匀程度。长时间的流速分布不均匀会造成载体流速较高处产生过高的气流速度和温度，致使催化剂径向温度梯度过大，从而产生热应力梯度，引发热疲劳破坏，使催化剂加速劣化，降低其使用寿命。而还原剂分布不均将造成氨分布局部过量或者不足，导致SCR催化效率降低和氨气泄漏，使催化剂老化不均，影响整体催化性能，为在SCR混合器中获得最大脱硝率和最小氨泄漏率的性能，必须使得UWS在载体前端面尽可能均匀分布。其均匀性系数表示如下：
Figure PCTCN2018106921-appb-000002
式中，Vi为单元载体法向速度，Vmean为载体进气口端面法向平均速度，A为单元截面积，Ai为界面网格总数。
1.1、速度均匀性
4种扰流结构结构的速度场分布如图6所示。加装网格通道板扰流结构进气管下游中部的气流较为平顺，承载件201管内轴向速度稳定，管内速度均匀性表现较好(图6(a))；由于中部大叶片结构的存在，导致扰流结构下游生成两排低速区域，而挡板缝隙下游处速度较高，管内速度分布极不均衡(图6(b))； 双层旋叶结构可以有效加速气流的周向旋转使管壁处产生强劲的旋流，进而促进汽液混合，但混合管中部气体流速相对较低(图6(c))；在复合式扰流结构中部加装的第一扰流件101明显改善了单纯使用旋叶结构的速度均匀性(图6(d))；在扰流结构近壁面处不仅制造了较强劲的旋流，而且还使得管壁处气流速度明显高于未装有旋转叶片结构。废气在承载件201管内的轴向速度强度同时也获得较好的持续性。
UWS在扰流结构载体前气流沿轴向距离的速度均匀性直接关系到催化剂的利用率。不同扰流结构下的载体前端面10厘米长度范围内轴向各截面速度均匀性如图7所示；Case1和Case2在混合腔内8厘米处的速度均匀性出现了骤减现象，最低值分别为0.64和0.72；整体速度均匀性明显低于Case3和Case4；虽然Case3在离载体0～8厘米处均匀性指数最高，但在9厘米处Case3中也出现了速度均匀性骤减现象，但相较case1和case2最低值提高至0.79；Case4是唯一未出现速度均匀性骤减现象的试件，这使得其在载体前10cm区域内均匀性指数达到了8.3以上，显著提高了混合腔内速度分布均匀性，可有效消除低速流速区域的死角。
为进一步明确载体端面外界气流对载体内部稳定性的影响，我们对载体内部1cm处的速度分布均匀性进行监测，如图8所示。从整体来看，四种结构的速度差别并不明显。当扰流结构为网格式结构时(图8(a)、(d))，扰流结构中部对气流扰动影响较小，废气在经由扰流结构处获得了较为强劲的湍动能，其速度均匀性较好。当扰流结构结构为挡板式和双层旋叶式时，存在大片低速区域，径向速度梯度较大，载体端面的速度均匀性变差(图8(b)、(c))。这将导致载体前端受热不均，会在一定程度上降低其使用寿命。
1.2氨均匀性
混合腔内的还原剂均匀指数是衡量混合器能否持续获得最大脱硝率和最小氨泄漏量的重要指标。图9为加载不同扰流结构时载体前方10cm处轴向截面氨均匀指数分布。case1和case2的板状叶片扰流结构结构可以产生轴向稳定的层流运动，但无法克服混合板对其气流的扰动，这导致了两方案均在8cm处混合板附近存在明显的指数突降区域，氨均匀性最低至0.53和0.57。而带有旋叶结构的case3和case4扰流结构通过制造周向旋转气流的方式，有效的消除了混合板所造成的氨均匀指数骤减现象，同时保证混合腔内轴向氨浓度分布指数始终保 持在0.75以上，是case1和case2的近1.5倍。
同样，我们也对载体前端面1cm内氨均匀性分布进行了检测(图10)；Case1整体氨分布较为均匀，但在左下方可观察到存在高浓度区域(图10(a))；Case2，因其混合挡板大都与水平面夹角为70°且方向向下，这使得氨蒸汽分布下多上少，而且存在严重的偏心现象(端面左下方红色区域)，不利于整体催化性能(图10(b))；双层旋叶结构有效的解决了case1与case2中左下方的高浓度区域集中问题，但由于case3扰流结构中部为旋流能量集中区域，高浓度区域上移至端面近圆心处(图10(c))。复合式扰流结构所产生的耦合效应显著改善了其他三种方案中氨浓度局部过高的问题，其还原剂分布均匀性明显好于其他三种方案(图10(d))。
Table2反应了载体内部1cm处速度均匀性以及氨均匀性指数。从表中我们可以看出，传统的case1在速度均匀性上具有优势，而case3则在氨均匀性上具有优势。本文设计的新型复合式扰流结构不但较好的结合了case1和case3的优点，而且速度均匀性和氨均匀性还同时得到了一定的提高，分别提升到了0.993和0.924。对于组份均化和传质来说，当废气进入进气管时，经由扰流结构外侧叶片的气流被分割形成大尺度的涡旋，使得近壁面气流旋转产生涡流，促进管壁处传质。同时，在管壁处的旋流带动经由中部网格挡板拉伸、剪切过的气流旋转，使其在强制对流作用下通过涡流扩散和分子扩散，进而达到气液相充分混合的目的，实现了同时提高速度和氨分布均匀性的目的。
Table2载体内1cm处均匀性指数
Figure PCTCN2018106921-appb-000003
2结晶性能
在尿素喷射过程中，大量液滴由于惯性与扰流结构及和管壁产生碰撞冲击，壁面温度随碰撞的激烈程度升高而降低，当壁面温度低于莱顿佛瑞斯特点(Leidenfrost point)后，碰壁液滴会在壁面沉积形成液膜。液膜在气流影响下 会持续蒸发、剥落、脱离，当此过程进行不完全时壁面结晶物得以形成。
结合现有研究可知，壁膜温度水平是决定相关沉积物化学性质的主要因素。有三种主要形式：易产生尿素结晶(T≤133℃)，尿素缓慢热解(133℃<T<163℃)和快速尿素分解同时伴有二次反应(T≥163℃)，高沉积风险区域的壁膜温度在大约160℃和170℃之间，结晶一旦在低温工况中形成，不但会造成排气管堵塞背压升高，而且将改变流场分布，降低混合器工作效率。
2.1扰流结构液膜温度分布
扰流结构液膜温度分布如图11。在case1中下部分叶片存在大面积低温区域(T<133℃)，扰流结构液膜最大温差在102～110℃(图11(a))。case2中，中下部第三排挡板处存在低温区域(T<155℃)(图11(b))，其他部分挡板温度分布均匀且温度大都在200℃以上，由此可见采用大叶片结构可在一定程度上改善壁面液膜温度。旋叶状扰流结构case3位于喷嘴直喷部位的叶片末端与第二层旋叶处存在明显低温液膜聚集区域(图11(c))。case4温度分布情况要好于其他三种方案，扰流结构中部网格板区域受热均匀，低温区域主要分布于扰流结构与管壁底部连接处的三个叶片上(图11(d))，此处叶片可能产生液膜沉积现象。
2.2扰流结构液膜厚度分布
当依附于壁面的液膜蒸发、分解速率持续低于新形成的液膜时便会产生液膜沉积现象。四种扰流结构在尿素喷射下液膜厚度分布如图12所示，case1中液膜主要聚集在扰流结构最下方两排壁面处图12(a))，且范围较广，沉积比较严重。case2的第三层外侧叶片及中部叶片存在片状液膜堆积(图12(b))，在此部位存在较大结晶风险。旋叶状扰流结构中央处(图12(c))可观察到大片带状液膜。(图12(d))case4中扰流结构液膜液厚度范围，还原剂在壁面上无片状沉积带形成，仅在底部旋叶上能观察到少许斑点状沉积带。
通过对比图11和图12发现，液膜温度在一定程度上决定了扰流结构液膜厚度分布以及生成沉积物部位。在温度低于156℃区域的发生液膜积聚现象的几率要明显高于其他部位。同时，我们可以观察到虽然在case3和case4旋叶部分存在大范围温度较低区域，但是液膜沉积部位要远小于低温区域的面积。这是因为较高的近壁面处空气流速，使得液滴无法在旋叶上长时间停留聚集，从而降低沉积物形成风险。
2.3扰流结构及管壁温度分布
如图13为垂直于管壁的扰流结构下游方向径向温度分布(管壁直径8cm)，横坐标轴0为上边缘靠近喷嘴处，8为下边缘与管壁底部接触部位，右端为扰流结构接触管壁部位。从图中可观察到喷雾颗粒刚开始接触到扰流结构壁面时，case1的上部区域温度为172℃，相较其他三种类型要低30℃左右，网格板部位温度分布差异较小。在case2中下部6cm可观察到明显降温，此现象持续到扰流结构与壁面接触部位，最终降低至178℃，case3在底部7cm处开始也发生此现象，温度降至182℃，在此形成低温区域将导致液滴无法迅速热解，致使结晶风险升高。此现象在case4中得到了明显改善，使得扰流结构下游温度保持在195℃以上。
尽可能高的温度分布有利于加速液滴热解，降低扰流结构下游管壁形成沉积物几率。图14为扰流结构与壁面底部接触点下游处轴向14cm温度分布，横坐标轴左端为扰流结构与管壁接触点，右端为距离此点14cm处位置。case1温度区间为195～207℃，波动幅度小，温度分布较为理想。case2壁面区域温度均值在四种方案中最低，且在6～9cm处存在连续低温区域，温度最低降至153℃，比较容易形成结晶。Case3虽然在5～9厘米处管壁温度显著降低，但整体温度区间为174～214℃，最低值仍大于高沉积物形成风险温度(T<170℃)。Case4温度分布范围为189～211℃，整体保持在较高的温度水平，复合式扰流结构对于下游管壁的传热效果要明显优于case2和case3。
2.4管壁液膜分布
观察下列管壁液膜分布图可知，case1在管壁侧翼图15(a)与图16(a)管壁底部气流行进方向存在大面积液膜沉积。case2沿管壁周向液膜沉积区域较小(图15(a))，沉积物大部分集中于管壁底部(图16(a))，此部分存在极大结晶风险。case3的沉积区域主要集中于扰流结构与管壁接触底部沿周向区域(图15(c))，管壁底部(图16(c))未观察到明显液膜聚集区。case4中可观察到管壁底部存在少许液膜(图16(d))，而管壁周向液膜形成区域面积最小(图15(d))，这说明外侧旋叶结构使管壁周向结晶风险得到显著降低，但是轴向存在一定的结晶风险。
2.5实验结果
扰流结构上游和下游结晶试验沉积物分布分别如图17和图18所示。从这 2个图可看出扰流结构上游和下游结晶沉积物几乎呈现对称现象。
Case1网格式扰流结构的结晶物主要集中在喷嘴直喷部分(图17(a))，这与仿真分析的结果大致保持一致图11(a)。其主要原因是该区域由于低温而造成液膜积聚，乃至形成结晶物。同理，由于大量的液膜沉积图15(a)导致了最终在壁面处形成较多结晶物图18(a)。
Case2从扰流结构中下部第三排挡板开始的液膜沉积区域图12(b)结晶物开始形成(图12(b))，聚集成块堵塞排气管道。同样，扰流结构下游液膜分布处图16(b)壁面有大量结晶物附着图18(图(b))。
case3旋叶式扰流结构在叶片夹层处产生严重的结晶图17(c)，块状结晶物的形成是由于扰流结构下方叶片液膜区域较大图12(c)，从而产生积聚效应导致扰流结构底部叶片受热不均无法使还原剂快速热解。扰流结构下游管壁部位较少，壁面光滑洁净图18(c)。
Case4复合式扰流结构上结晶物最少，管壁处结晶量相较于case1显著降低，这主要是由于外围叶片使得气流旋转增加近壁面气流流速，较好的改善了壁面处传热和传质情况，使得液膜不易在此积聚，有效降低了壁面结晶风险。扰流结构只在网格挡板中下部有少量结晶物依附，结晶量明显少于case1，且未产生块状结晶物堵塞管道图17(d)。这是因为外侧旋流使中部网格板处气流进行周向运动，减少液滴在此部分壁面停留时间，有效降低液膜沉积区域的形成风险。2.6结晶物重量
将加载四种扰流结构的部位拆卸进行称重，如图19，通过比较实验前后体系的重量差来获得沉积物重量(测量精度为±0.01g)。从图中发现，扰流结构结晶重量从case1到case3逐渐增加，而case4的结晶重量最小为2.31g，分别是case1、case2、case3的34.7％、22.6％、16.7％。实验数据表明，双层旋叶结构虽然可以获得较好的氨均匀性，但是极易在低温工况下形成大块结晶物，带有网格通道板这种几何结构的扰流结构可有效改善混合器在低温工况下的结晶性能。
3、背压损失
背压增大会增大排气阻力，降低发动机动力和燃油经济性。混合器在进行结构优化设计时尽可能在获得较高均匀性指数的同时，降低混合器对排气系统的背压损失。图20为四种扰流结构背压损失情况，从图中可看出case4复合式 扰流结构的背压损失近似于case1的背压损失，但前者的氨均匀性较后者提高了6.7％。同时，case4与case3在氨均匀性比较接近的情况下，前者的压力损失相较于后者有效降低了139Pa。综上所述，case4的扰流结构具有较好的综合性能。
结论
本研究通过仿真和实验的手段对所设计的新型扰流结构结构的低温工况下还原剂混合均匀性及结晶性能进行了分析和验证，其主要结果如下所示：
(1)基于改善低温排放下尿素液滴蒸发特性，本研究结合现有扰流结构结构提出新型复合式扰流结构结构。通过对四种不同扰流结构进行喷雾模拟，较为准确的预测了扰流结构及壁面结晶形成部位。新型扰流结构在低温工况下结晶量大幅降低，显著提高了混合器在低温工况下的抗结晶形成性能。
(2)通过结构优化设计，使得氨均匀性指数分别比case1、case2、case3提高6.7％、3.1％、0.07％。而且在获得相同氨均匀性的情况下(与case3相比)，使排气背压降低7.8％。
(3)在扰流结构上加装旋叶结构可有效增加气体在近管壁处流速提高组份均化效果，同时提升管壁温度，降低管壁结晶物形成风险。而密集的网格挡板结构可以提高气流的速度均匀性。
应说明的是，以上实施例仅用以说明本发明的技术方案而非限制，尽管参照较佳实施例对本发明进行了详细说明，本领域的普通技术人员应当理解，可以对本发明的技术方案进行修改或者等同替换，而不脱离本发明技术方案的精神和范围，其均应涵盖在本发明的权利要求范围当中。

Claims (10)

  1. 一种应用于尾气处理的扰流结构，其特征在于：所述扰流结构(100)包括，
    第一扰流件(101)，包括格栅(101a)、挡板(101b)和第一外围壁(101c)，所述挡板(101b)设置于所述格栅(101a)上，所述第一外围壁(101c)设置于所述格栅(101a)的外围；以及，
    第二扰流件(102)，所述第二扰流件(102)包括旋叶(102a)和第二外围壁(102b)，所述第二外围壁(102b)设置于第一外围壁(101c)的外围，所述旋叶(102a)介于所述述第二外围壁(102b)和第一外围壁(101c)之间。
  2. 如权利要求1所述的应用于尾气处理的扰流结构，其特征在于：所述格栅(101a)包括横基板(101a-1)和纵基板(101a-2)，所述横基板(101a-1)与纵基板(101a-2)交叉设置。
  3. 如权利要求2所述的应用于尾气处理的扰流结构，其特征在于：所述横基板(101a-1)与纵基板(101a-2)构成的平面(N)与所述挡板(101b)呈一定夹角排布。
  4. 如权利要求1～3任一所述的应用于尾气处理的扰流结构，其特征在于：所述挡板(101b)区分为第一朝向体(101b-1)和第二朝向体(101b-2)，所述第一朝向体(101b-1)和第二朝向体(101b-2)相邻设置，且相邻的第一朝向体(101b-1)和第二朝向体(101b-2)反向交错设置。
  5. 如权利要求4所述的应用于尾气处理的扰流结构，其特征在于：所述第一朝向体(101b-1)和第二朝向体(101b-2)均设置于所述纵基板(101a-2)上。
  6. 如权利要求4或5所述的应用于尾气处理的扰流结构，其特征在于：所述第一外围壁(101c)和第二外围壁(102b)均为圆环结构。
  7. 如权利要求6所述的应用于尾气处理的扰流结构，其特征在于：所述旋叶(102a)包括第一端面(102a-1)、第二端面(102a-2)、第三端面(102a-3)和第四端面(102a-4)，所述第一端面(102a-1)、第二端面(102a-2)、第三端面(102a-3)和第四端面(102a-4)首尾依次连接；
    其中，所述第二端面(102a-2)与第四端面(102a-4)均为弧形结构，所述第二端面(102a-2)设置于所述第四端面(102a-4)的外围。
  8. 如权利要求7所述的应用于尾气处理的扰流结构，其特征在于：所述第一端面(102a-1)、第二端面(102a-2)、第三端面(102a-3)和第四端面(102a-4) 的连接处依次为第一交边(n1)、第二交边(n2)、第三交边(n3)和第四交边(n4)；
    其中，所述第一交边(n1)和第二交边(n2)分别与所述第一外围壁(101c)的两端边连接；
    其中，所述第三交边(n3)和第四交边(n4)分别与所述第二外围壁(102b)的两端边连接。
  9. 一种复合式SCR混合器，其特征在于：所述混合器依托于如权利要求1～8所述的扰流结构(100)应用，
    其中，所述混合器还包括混合配件(200)，所述扰流结构(100)设置于所述混合配件(200)内。
  10. 如权利要求9所述的复合式SCR混合器，其特征在于：所述混合配件(200)包括承载件(201)和喷洒件(202)，所述喷洒件(202)呈一定角度嵌入设置于所述承载件(201)内；
    其中，所述喷洒件(202)的喷口朝向所述扰流结构(100)的格栅(101a)。
PCT/CN2018/106921 2018-07-27 2018-09-21 一种应用于尾气处理的扰流结构以及复合式scr混合器 Ceased WO2020019463A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201810844570.7A CN108843432A (zh) 2018-07-27 2018-07-27 一种应用于尾气处理的扰流结构以及复合式scr混合器
CN201810844570.7 2018-07-27

Publications (1)

Publication Number Publication Date
WO2020019463A1 true WO2020019463A1 (zh) 2020-01-30

Family

ID=64195744

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2018/106921 Ceased WO2020019463A1 (zh) 2018-07-27 2018-09-21 一种应用于尾气处理的扰流结构以及复合式scr混合器

Country Status (2)

Country Link
CN (1) CN108843432A (zh)
WO (1) WO2020019463A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN122230579A (zh) * 2026-05-19 2026-06-19 武汉理工大学三亚科教创新园 一种具有被动旋转扰流组件的乳化混合器

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109578116B (zh) * 2018-11-27 2020-10-27 安徽江淮汽车集团股份有限公司 一种防止尿素结晶的scr后处理系统
CN111577431A (zh) * 2020-05-11 2020-08-25 江苏科技大学 船用scr系统混合器
CN112459873A (zh) * 2020-11-12 2021-03-09 南京德普瑞克催化器有限公司 扰流预燃机构和包含其的扰流触媒催化器组件
CN112964475A (zh) * 2021-03-24 2021-06-15 柳州职业技术学院 一种用于scr混合器的导流测量装置及测试方法

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2009157995A1 (en) * 2008-06-26 2009-12-30 Tenneco Automotive Operating Company, Inc. Exhaust gas additive/treatment system and mixer for use therein
CN102027216A (zh) * 2008-04-25 2011-04-20 坦尼科汽车营业公司 排气添加剂/处理系统和用于在其中使用的混合器
CN102725056A (zh) * 2009-12-18 2012-10-10 雷诺卡车公司 用于排气后处理设备的混合系统
CN102985654A (zh) * 2010-07-08 2013-03-20 斗山英维高株式会社 用于混合尿素水溶液和发动机尾气的静态混合器
CN105715339A (zh) * 2014-12-17 2016-06-29 奥迪股份公司 具带有防粘附覆层的液体还原剂混合器的内燃机排气设备

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ITMI20050655A1 (it) * 2005-04-15 2006-10-16 Iveco Spa Miscelatore statico
CN201776091U (zh) * 2010-08-17 2011-03-30 广西玉柴机器股份有限公司 一种混合器
JP5688963B2 (ja) * 2010-12-17 2015-03-25 Ｕｄトラックス株式会社 エンジンの排気浄化装置
US9302223B2 (en) * 2014-06-13 2016-04-05 Caterpillar Inc. Mixing element
CN105201604B (zh) * 2015-10-27 2018-05-29 南京依柯卡特排放技术股份有限公司 一种scr系统尿素混合器
CN105715341A (zh) * 2016-02-15 2016-06-29 东风朝阳朝柴动力环保科技有限公司 选择性催化还原系统混合扰流器
CN105804840B (zh) * 2016-05-16 2020-08-04 天纳克（苏州）排放系统有限公司 排气处理装置

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102027216A (zh) * 2008-04-25 2011-04-20 坦尼科汽车营业公司 排气添加剂/处理系统和用于在其中使用的混合器
WO2009157995A1 (en) * 2008-06-26 2009-12-30 Tenneco Automotive Operating Company, Inc. Exhaust gas additive/treatment system and mixer for use therein
CN102725056A (zh) * 2009-12-18 2012-10-10 雷诺卡车公司 用于排气后处理设备的混合系统
CN102985654A (zh) * 2010-07-08 2013-03-20 斗山英维高株式会社 用于混合尿素水溶液和发动机尾气的静态混合器
CN105715339A (zh) * 2014-12-17 2016-06-29 奥迪股份公司 具带有防粘附覆层的液体还原剂混合器的内燃机排气设备

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN122230579A (zh) * 2026-05-19 2026-06-19 武汉理工大学三亚科教创新园 一种具有被动旋转扰流组件的乳化混合器

Also Published As

Publication number Publication date
CN108843432A (zh) 2018-11-20

Similar Documents

Publication Publication Date Title
CN108843432A (zh) 一种应用于尾气处理的扰流结构以及复合式scr混合器
CN110273734A (zh) 一种双向旋流筒式尿素混合装置
Zhang et al. Optimisation design of SCR mixer for improving deposit performance at low temperatures
US9718037B2 (en) Mixing system for aftertreatment system
KR101664494B1 (ko) 요소 수용액과 엔진 배기가스의 혼합을 위한 정적 혼합기
US20230143888A1 (en) Mixers for use in aftertreatment systems
CN106731932B (zh) 一种scr尿素溶液混合器
CN101900018A (zh) 一种尿素混合装置
CN110939530A (zh) 一种混合稳焰装置
Liao et al. Fluid dynamic comparison of AdBlue injectors for SCR applications
AU2020103469A4 (en) Detachable device for coupling cyclone type vehicle SCR mixer and nozzle
CN112084725A (zh) 一种柴油内燃机scr混合器性能的评价办法
CN113107650A (zh) 一种用于柴油机urea-SCR系统的动态混合器
WO2021018266A1 (zh) 尾气后处理装置
WO2021018265A1 (zh) 尾气后处理装置
CN105464764B (zh) 用于排气设施的混合器及scr系统
CN108180060A (zh) 混合装置以及柴油机后处理装置
CN202273735U (zh) 一种车用尿素scr系统及其静态混合器
CN103742238A (zh) 一种尿素scr系统低温加热混合装置
CN118129181A (zh) 氢气微混燃烧室
CN201972767U (zh) 一种用于柴油机尿素scr系统的混合器
Lu et al. A study on the high-efficiency mixer of the SCR system
CN211819593U (zh) 一种scr排气混合装置
CN209586477U (zh) 一种新型混合器
CN114941562B (zh) 柴油-氨双燃料发动机DeNOx用氨射流混合器及喷射方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18927496

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18927496

Country of ref document: EP

Kind code of ref document: A1