CN106030064B - In-line arrangement current divider - Google Patents

Abstract

It is a kind of for reduce the discharge gas processing system of the emission of engine to include exhaust manifolds, which is adapted to exhaust stream being supplied to exhaust gas treatment device from the engine.The conduit includes aperture.Reagent is ejected through the aperture and enters the exhaust stream by injector.Flow regulator is in the injector located upstream in exhaust manifolds.The flow regulator includes current divider, and the current divider is for increasing speed of pre-position of the discharge gas in conduit relative to the reagent sprayed.

Description

In-line shunt

technical field

The present disclosure relates to exhaust gas treatment systems. More specifically, an exhaust gas flow regulator is provided upstream of the reagent injector to enhance immobilization and distribution of reagent in the engine exhaust stream.

Background technique

This section provides background information related to the present disclosure which is not necessarily prior art.

In order to reduce the amount of undesirable particulate matter and _NOx emitted to the atmosphere during operation of internal combustion engines, various exhaust aftertreatment systems have been developed. Exhaust gas aftertreatment systems are especially required when implementing diesel combustion processes.

One method for reducing _NOx emissions from internal combustion engines is known as selective catalytic reduction (SCR). SCR may involve injecting a reagent into the engine's exhaust stream to form a mixture of reagent and exhaust gas, which is then passed over a catalyst containing a catalyst such as activated carbon or a catalyst such as platinum, vanadium, or tungsten that reduces the concentration of NO _x in the presence of the reagent. and other metals) reactors.

Aqueous urea is known to be an effective reagent in SCR systems for diesel engines. However, there may be disadvantages to using aqueous solutions and other reagents. Urea is highly corrosive and attacks the mechanical parts of the SCR system. Urea is also prone to solidification upon prolonged exposure to high temperatures as encountered in diesel exhaust systems. There is a concern because agents that generate deposits are not used to reduce _NOx .

Furthermore, if the reagent is not properly mixed with the exhaust gases, the reagent is not used efficiently, inhibiting the action of the catalyst and thereby reducing the effectiveness of the SCR system. High reagent injection pressures have been used as a way to minimize the problem of insufficient atomization of the urea mixture. However, high injection pressures may cause excessive penetration of the injected spray plume into the exhaust flow, thereby causing the plume to impinge on the inner surface of the exhaust pipe opposite the injector. Excessive breakthrough results in inefficient use of the urea mixture and may reduce the range over which the vehicle can operate with reduced NOx emissions. Only a limited amount of reagents can be carried in the vehicle. Efficient use of stored reagents is desirable to maximize vehicle range and reduce the need for refills.

It would be advantageous to provide methods and apparatus for injecting reagent into the exhaust flow of an internal combustion engine to minimize reagent deposition and improve mixing of the reagent with the exhaust gas.

Contents of the invention

This section provides a general overview of the disclosure rather than a comprehensive disclosure of its full scope or all of its features.

An exhaust gas treatment system for reducing emissions of an engine includes an exhaust conduit adapted to supply an exhaust flow from the engine to an exhaust treatment device. The conduit includes an orifice. An injector injects reagent through the orifice and into the exhaust stream. A flow regulator is positioned within the exhaust conduit upstream of the injector. The flow regulator includes a flow splitter for increasing the velocity of the exhaust gas relative to the injected reagent at a predetermined location within the conduit.

An exhaust gas flow regulator is provided for an exhaust gas treatment system including an exhaust conduit and an injector for injecting a reagent into the exhaust flow. The flow regulator includes a mounting joint adapted to secure the injector to the conduit. The mounting section includes an orifice through which reagent is sprayed. A flow splitter is coupled to one of the mounting node and the conduit, adapted to be positioned within the conduit, and offset from an inner surface of the conduit. The splitter is positioned upstream of the reagent injection orifice and is angled to increase the velocity of the exhaust gas at a predetermined location within the conduit and reduce the impact of the reagent on the inner surface of the conduit.

The present disclosure also provides an exhaust gas treatment system for reducing emissions from an engine. The system includes: an exhaust gas treatment device; an exhaust conduit adapted to supply an exhaust flow from the engine to the exhaust treatment device, the conduit including an orifice; an injector for for injecting reagent through the orifice and into the exhaust stream; and a flow regulator positioned within the exhaust conduit adjacent the injector. The flow conditioner includes a plate having a first end and a second end secured to opposite sides of the exhaust conduit so as to suspend the plate within the exhaust conduit, and the plate includes a plurality of Shutters that direct the exhaust flow in a direction toward or away from the injector.

Other applicability will be apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the disclosure.

Description of drawings

The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure.

1 depicts a schematic diagram of an exemplary internal combustion engine equipped with an emissions control system of a pre-injection exhaust gas flow regulator in accordance with the present teachings;

2 is an exploded perspective view of an exhaust gas treatment device including a pre-injection exhaust gas flow regulator;

3 is a partial cross-sectional side view of the exhaust gas treatment device;

Figure 4 is a graph depicting the exhaust gas velocity profile through a conduit not equipped with a pre-injection regulator;

Figure 5 depicts a computational fluid dynamics model of the mass fraction of reagent in a conduit without a flow regulator;

6 is a computational fluid dynamics contour plotting simulated spray concentrations of reagent droplets injected within a conduit without a pre-injection exhaust flow regulator;

Figure 7 depicts a computational fluid dynamics model of the mass fraction of reagent in a conduit with a flow regulator;

8 is a computational fluid dynamics contour plotting simulated spray concentrations of reagent droplets injected within a conduit with a pre-injection exhaust flow regulator;

Figure 9 is a partial perspective view of a semi-conical flow regulator;

Fig. 10 is a partial perspective view of a wedge-shaped flap flow regulator;

Figure 11 is a partial perspective view of another alternative pre-injection flow regulator;

Figure 12 is a cross-sectional side view of the flow regulator depicted in Figure 11;

Figure 13 is an end view of the flow regulator depicted in Figure 11;

14 is a graph depicting the velocity profile of exhaust gas flowing through a conduit equipped with a flow regulator as shown in FIG. 11;

Figure 15 is a plan view of another alternative flow regulator;

Figure 16 is a partial cross-sectional side view of the flow regulator shown in Figure 15;

17 is a partial cross-sectional side view of an exhaust conduit including a flow regulator located in an upper portion of the conduit in accordance with principles of the present disclosure;

18 is a partial cross-sectional side view of an exhaust conduit including a flow regulator located in a lower portion of the conduit in accordance with principles of the present disclosure;

19 is a front view of the exhaust conduit shown in FIG. 17 including a flow regulator; and

20 is a perspective view of the exhaust conduit shown in FIG. 17 including a flow regulator.

Corresponding reference characters indicate corresponding parts throughout the several views of the drawings.

Detailed ways

Example embodiments will now be described more fully with reference to the accompanying drawings.

It should be understood that while the present teachings may be described in connection with a diesel engine and reduction of NOx emissions, multiple exhaust streams such as from (by way of non-limiting example) diesel, gasoline, turbine, fuel cell , jet aircraft, or any other power source that outputs an exhaust stream) using this teaching. Furthermore, the present teachings may be used in connection with reducing any of a variety of undesired emissions. For example, injection of hydrocarbons for diesel particulate filter regeneration is also within the scope of the present disclosure. For additional clarification, attention should be paid to commonly assigned U.S. Patent No. 8,047,452, issued November 1, 2011, entitled "Method And Apparatus For Injecting Atomized Fluids" by Incorporated by reference.

Referring to the drawings, there is provided a pollution control system 8 for reducing NOx emissions from the exhaust of a diesel engine 21 . In FIG. 1 , the solid lines between the elements of the system represent fluid lines for reagents, and the dashed lines represent electrical connections. A system of the present teachings may include a reagent tank 10 for containing reagents, and a delivery module 12 for delivering reagents from tank 10 . The agent may be a urea solution, a hydrocarbon, an alkyl ester, an ethanol, an organic compound, water, etc., and may be a blend or combination thereof. It should also be understood that one or more reagents may be used in the system and may be used alone or in combination. Tank 10 and delivery module 12 may form an integrated reagent tank/delivery module. Also provided as part of the system 8 are an electronic injection controller 14 , a reagent injector 16 and an exhaust system 19 . The exhaust system 19 includes an exhaust conduit 18 supplying an exhaust flow to at least one catalyst bed 17 .

The delivery module 12 may comprise a pump that supplies reagents from the tank 10 through the supply line 9 . Reagent tank 10 may be polypropylene, epoxy coated carbon steel, PVC, or stainless steel and is sized according to the application (eg, vehicle size, intended use of the vehicle, etc.). A pressure regulator (not shown) may be provided for maintaining the system at a predetermined pressure set point (eg, a relatively low pressure of about 60-80 psi, or in some embodiments a pressure of about 60-150 psi) , and may be located in return line 35 from reagent injector 16 . A pressure sensor may be provided in the supply line 9 leading to the reagent injector 16 . The system can also incorporate multiple freeze protection strategies to thaw frozen reagents or prevent reagents from freezing. During system operation, regardless of whether the injector is releasing reagent into the exhaust gas, reagent may be continuously circulated between the tank 10 and the reagent injector 16 to cool the injector and increase the residence time of the reagent in the injector. Reduce to a minimum so that the reagents remain cool. Continuous reagent circulation may be necessary for temperature sensitive reagents, such as aqueous urea solutions, which tend to solidify when exposed to elevated temperatures of 300°C to 650°C, such as those experienced in engine exhaust systems.

Additionally, it may be desirable to keep the reagent mixture below 140°C, and preferably within the lower operating range of 5°C and 95°C, to ensure that the reagents are prevented from curing. The cured reagent (if allowed to form) can then contaminate moving parts and injector openings.

The amount of reagent required may vary with load, exhaust gas temperature, exhaust gas flow, engine fuel injection timing, desired NOx reduction, barometer pressure, relative humidity, EGR ratio, and engine coolant temperature. A NO _x sensor or meter 25 is positioned downstream of the catalyst bed 17 . The NO _x sensor 25 is operable to output a signal indicative of the exhaust NO _x content to the engine control unit 27 . All or some of the engine operating parameters may be provided to the reagent electronic injection controller 14 from the engine control unit 27 via the engine/vehicle data bus. The reagent electronic injection controller 14 may also be included as part of the engine control unit 27 . Exhaust gas temperature, exhaust gas flow and exhaust back pressure as well as other vehicle operating parameters can be measured by means of corresponding sensors.

Referring now to FIGS. 2-8 , an exhaust gas treatment assembly 100 is defined including an exhaust conduit 18 and an injector 16 . Exhaust conduit 18 includes a substantially cylindrical tube 102 that defines an exhaust passage 104 . Cylindrical tube 102 includes an inner surface 106 and an outer surface 108 .

Injector 16 includes a body 150 defining a cylindrical chamber 152 that receives an axially translatable valve member 154 . The body 150 includes an outlet hole 156 as a discharge location for the injected reagent. A valve seat 146 is formed adjacent to outlet aperture 156 and selectively engages valve member 154 to control injection of reagent into the exhaust gas flow path. Valve member 154 is translatable along reagent injection axis 158 .

Mounting section 160 is secured to body 150 and includes a radially outwardly extending flange 162 . A flow conditioner 164 extends radially inward from mounting nub 160 into tube 102 to redirect the flow of exhaust gas through exhaust passage 104 . Clamps (not shown) or other suitable coupling means secure mounting section 160 to tube 102 .

The flow regulator 164 includes a radially inwardly extending post 166 having a first end 168 secured to a mounting segment 160 and an opposite end 170 secured to a substantially planar diverter plate 172 . Splitter plate 172 is positioned at an oblique angle to the direction of exhaust flow through tube 102 . In the embodiment depicted in FIG. 2 , splitter plate 172 includes an elongated oval shape.

Flow regulator 164 and mounting section 160 are shown as a one-piece component that can be easily secured to tube 102 using typical injector mounting hardware. It is also contemplated that flow regulator 164 may be spaced from mounting section 160 , positioned within exhaust passage 104 , and separately secured to cylindrical tube 102 . In the version depicted in FIG. 2 , tube 102 includes keyhole slot 173 shaped to receive flow regulator 164 .

Flow regulator 164 is positioned upstream of reagent injection axis 158 . The flow regulator 164 is sized, shaped and positioned within the passageway 104 to vary the velocity profile of the exhaust gas in a cross-sectional plane taken along the reagent injection axis 158 . In the absence of a flow regulator, the exhaust flow velocity profile through tube 102 exhibits a substantially symmetrical curved trajectory, increasing to a maximum velocity at the center of passageway 104 and minimum velocity at inner surface 106, as shown in FIG. The velocity of the exhaust gas near the inner surface 106 is substantially lower than the velocity of the exhaust gas at the center of the tube 102 . When the exhaust gas flow rate is relatively low, such as when the internal combustion engine is idling, the injected reagent tends to pass through the exhaust gas and impinge on the inner surface 106 along the lower half of the tube 102 ( FIG. 3 ). As previously mentioned, it is desirable to mix reagents with the exhaust gas and supply the mixture to an exhaust treatment device, such as an SCR catalyst. Reagents impinging on inner surface 106 may tend to adhere to tube 102, causing undesirable pooling, corrosion, and possible reagent solidification.

Figure 5 depicts CFD contours showing that for an exhaust system without a flow regulator, at a relatively low exhaust flow rate of about 380 kg/hour, the reagent is injected at about 4.2 grams per minute Mass fraction distribution in the process. Figure 6 also provides a simulated reagent spray concentration contour map at the same exhaust flow rate and reagent injection rate. Both Figure 5 and Figure 6 plots relate to exhaust flow and reagent injection in a cylindrical tube without a flow regulator.

FIG. 7 depicts reagent mass fraction contours for the same exhaust flow and reagent injection rate for a system equipped with a flow regulator shaped as splitter plate 172 . Figure 8 shows the corresponding reagent spray concentration contours. Comparing the contours produced without the flow splitter to that with the inclusion of the splitter plate 172 demonstrates the effect of increasing the exhaust velocity near the reagent outlet orifice 156 . By increasing velocity in the region where the reagent is initially sprayed, the reagent droplet is forced to move up and/or further downstream before traversing the tube and impacting the inner surface 106 opposite the injector 16 .

Additional calculated estimates are generated regarding the concentration of injected reagent throughout passage 106 . Specifically, the amount of reagent deposited on the lower half of the tube wall surface was estimated when the exhaust gas flow rate was 380 kg/hour and the reagent injection rate was about 4.2 g/min. By installing the flow regulator 164, the mass fraction of reagent deposited on the lower half of the inner surface 106 is reduced by more than 50%.

A further review of the computational fluid dynamics data reflects that the splitter plate 172 induces flow splitting at the leading edge 174 , causing the exhaust flow to accelerate towards the injector 16 . At the trailing edge 176 of the splitter plate 172 , the exhaust flow velocity increases by 25% in the area between the splitter plate 172 and the injector 16 . The result is enhanced mixing and reduced reagent shock.

FIG. 9 depicts an alternative flow regulator 200 . As previously discussed with respect to flow regulator 164 , flow regulator 200 may be affixed to the injector mounting joint or may be spaced separately from injector 16 and coupled to tube 102 . Flow regulator 200 includes a post 202 having a substantially planar shape extending radially into passage 104 . The semi-conical flap 204 is fixed to the column 202 . The semi-conical flap 204 includes a partially conical outer surface 206 spaced from a partially conical inner surface 208 . The semi-conical flap 204 ends at a first edge 210 and a second edge 212 . First edge 210 is spaced from second edge 212 to allow post 202 to pass therebetween. The axis of rotation 216 of the conical outer surface 206 extends at an angle relative to the direction of exhaust gas flow through the passageway 104 so as to increase the velocity of the exhaust gas flow in the vicinity of the injector 16 . CFD analysis indicated favorable reagent to exhaust mixing and reduced impact of the reagent on the inner surface 106 opposite the injector 16 .

As shown in FIG. 10 , another alternative flow regulator is identified at reference numeral 300 . The flow conditioner 300 includes a wedge-shaped flap 302 upstream of the injector 16 that projects inwardly from the inner surface 106 . The wedge-shaped flap 302 includes a conical wall 304 starting at a point 306 and ending at a substantially planar face plate 308 . The wedge flap 302 is also used to adjust the discharge gas velocity profile upstream of the injector 16 to enhance mixing and reduce reagent impact on the inner surface 106 .

Another type of flow regulator, identified at reference numeral 500, is depicted in FIGS. 11-13. The flow conditioner 500 is shaped as a substantially planar plate 502 secured within a substantially cylindrical tube 504 . The plate 502 is inclined in a direction opposite to the direction of the splitter plate 172 . Specifically, the upstream edge 508 of the plate 502 is positioned closer to the injector 16 than the downstream edge 510 of the plate 502 . The exhaust flow is split as it crosses the leading edge 508 such that the top of the flow will expand and slow down slightly, while the bottom of the flow will compress and cause an increase in velocity. The increased velocity in the lower part of the tube will blow away the reagent droplets that reach the lower part of the tube before they evaporate. Thus, flow regulator 500 will reduce tubing wetting due to reagent impingement.

If the angle of the plate 502 within the tube 504 is steep enough, the top of the tube will experience boundary layer slippage, causing turbulence to help reagent and exhaust mix. In one embodiment, an afterspray mixer such as that described in US Patent No. 8,141,353, which is incorporated herein by reference, may be included. Turbulent flow into the mixer will enhance the ability of the mixer to distribute the reagents throughout the exhaust gas. In this way, the mixing length can be shortened. Alternatively, by properly positioning the plate 502 upstream of the injector 16, the after-spray mixer can be eliminated.

FIG. 14 presents the velocity curves of the exhaust at four different axial positions downstream of the inclined plate 502 . A first velocity profile at the trailing edge 510 of the plate 502 is plotted. As seen in FIG. 14 , the next profile on the right depicts the exhaust gas velocity profile at an axial distance of one inch downstream from trailing edge 520 . Velocity distributions at offset distances of six inches and offset distances of twelve inches are also shown. Based on computational fluid dynamics modeling, injector 16 may be beneficially placed at an axial location aligned with, or within about 1 inch of, trailing edge 510 to take advantage of the increased speed curve.

It should also be understood that the plate 502 may be fixed within the tube 504, or may be movably mounted therein. For a movably mounted version, it is contemplated that the plate 502 may be pivotally coupled to the tube 504 in a manner similar to the snap action valves described in US Patent No. 7,434,570, incorporated herein by reference. Additional movable valves are described in US Patent Nos. 7,775,322, 8,215,103, and 8,468,813, also incorporated herein by reference. Each of the cited references includes a torsion spring and a passively actuated valve that rotates with respect to the exhaust pressure acting thereon. It is also contemplated that the present flow regulator may be actively controlled through the use of an actuator (not shown) operable to position the plate 502 substantially parallel to the direction of exhaust flow as previously discussed. Rotate between tilted positions.

15 and 16 depict biased flow regulator 600 pivotally coupled to tube 602 . The flow regulator 600 is movable between a deployed position and a retracted position to minimize restriction of higher exhaust flow rate flow. When the exhaust flow rate through tube 102 is sufficiently high, additional flow adjustment is not required to obtain adequate reagent mixing and avoid reagent shock. At these higher exhaust gas flow rates, it may be beneficial to retract the flow regulator from its deployed position.

Torsion spring 604 biases flap 606 toward the deployed position depicted in the figure. The flap 606 is curved to deflect the flow of exhaust gas away from the injector 16 and to increase the velocity of the exhaust gas attached at the inner surface 608 opposite the injector 16 . When the exhaust flow rate reaches a predetermined magnitude, the force on the upstream surface 610 of the flow regulator 600 overcomes the biasing force of the spring 604 , thereby causing the flap 606 to move toward the retracted position adjacent the inner surface 608 . When the flow regulator 600 is in the retracted position, restriction to exhaust flow is minimized. Any increase in back pressure due to use of the flow regulator 600 will be minimized.

FIG. 17 illustrates another flow regulator 700 in accordance with the principles of the present disclosure. The flow conditioner 700 is a curved plate 702 including a first edge 704 and a second edge 706 secured to an exhaust pipe 708 such that the plate 702 is suspended over the exhaust at a location upstream of the injector 16. inside the tube 708 . Although the plate 702 is shown as being curved, the plate 702 may be substantially planar without departing from the scope of this disclosure. A plurality of louvers 710 may be formed in the plate 702 to direct the exhaust flow in a desired direction. In the illustrated embodiment, the flow regulator is secured to the exhaust pipe 708 at its upper portion 712 (ie, on the same side of the pipe 708 as the injector 16). As the exhaust flow approaches the flow regulator 700 , the shutter 710 will direct the exhaust flow in a downward direction away from the injector 16 . In this manner, droplets of the reagent exhaust treatment fluid may be prevented from reaching the lower portion 713 of the tube 708 and pooling or forming deposits thereon.

Alternatively, the flow regulator 700 may be secured to the exhaust pipe 708 at its lower portion 713 (FIG. 18). The shutter 710 will then direct the exhaust flow up and towards the injector 16 . Regardless of where the flow regulator 700 is positioned, the increase in velocity and swirl caused by the shutter 710 will cause the reagent exhaust treatment fluid to mix with the exhaust flow such that deposit formation is prevented or at least substantially minimized. Further, it should be understood that, whether positioned in the upper portion 712 or the lower portion 713, the flow regulator 700 may include the shutter 710 oriented in the opposite configuration to that shown. That is, when the flow regulator 700 is positioned in the upper portion 712 of the tube 708 , the shutter 710 may be oriented to direct the flow of exhaust toward the injector 16 . Alternatively, the shutter 710 may be oriented to direct the exhaust flow away from the injector 16 when the flow regulator 700 is positioned in the lower portion 712 of the tube 708 . Another alternative is to orient the shutter 710 in either direction, regardless of whether the flow regulator 700 is positioned in the upper portion 712 or the lower portion 713 of the tube 708 .

The shutter 710 can be adjusted as desired. For example, the shroud 710 may be in the form of a tab 714 protruding from the plate 702 . Tabs 714 may each include a different length, which allows for tailoring of the non-uniform target flow distribution of the exhaust. Alternatively, the shutter 710 may have any shape desired by those skilled in the art. For example, shutter 710 may be oval, circular, triangular, etc. without departing from the scope of this disclosure. Additionally, the shroud 710 may be slightly helically twisted to induce a greater amount of swirl in the exhaust flow that assists in mixing the reagent exhaust treatment fluid with the exhaust. As best shown in FIG. 20 , the shutters 710 are staggered on the plate 702 , which allows for increased exhaust flow redirected by the flow conditioner 700 .

Flow regulator 700 should not be limited to being positioned upstream of injector 16 . Instead, flow regulator 700 may be positioned directly below injector 16 , or may be positioned downstream of injector 16 . When flow regulator 700 is positioned directly below injector 16 , large droplets of reagent exhaust treatment fluid that are not immediately atomized and mix with the exhaust may impinge on plate 702 . Although large droplets may impact the plate 702, because the flow conditioner 700 can be suspended within the tube 708, the droplets are subject to higher velocity exhaust flow, which generally causes the droplets to sublimate rather than form deposits things.

Furthermore, it should be understood that the flow regulator 700 should not be limited to use with the injector 16 . In contrast, it should be understood that the injector 16 could be replaced with, for example, a NOx sensor 25, a temperature sensor, a pressure sensor, and the like. The use of the flow regulator 700 in conjunction with the sensor allows for non-uniform flow of exhaust gas, which can provide more accurate readings of exhaust gas temperature, NOx concentration, etc. due to its proximity to the sensor.

The foregoing description of these embodiments has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit this disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment even not explicitly shown or described. It can also be varied in various ways. Such variations are not to be regarded as a departure from this disclosure, and all such modifications are intended to be included within the scope of this disclosure.

Claims (25)

1. a kind of discharge gas processing system for reducing the emission of engine, the discharge gas processing system include：

Exhaust gas treatment device；

Exhaust manifolds, the exhaust manifolds are adapted for exhaust stream being supplied to the exhaust gas treatment device from the engine, should Exhaust manifolds include aperture；

Injector, the injector are used to reagent being ejected through the aperture and enter the exhaust stream；

Flow regulator, the flow regulator are located in adjacent to the injector in the exhaust manifolds,

The discharge gas processing system is characterized in that,

The flow regulator includes the twisted plate having a first end and a second end, which is fixed to the exhaust and leads The opposite side of pipe is the twisted plate to be suspended in the exhaust manifolds, which includes multiple shields, these shields are with direction Or the direction far from the injector guides the exhaust stream.

2. discharge gas processing system as described in claim 1, wherein these shields are the contact pin by being pierced by from the twisted plate It is formed.

3. discharge gas processing system as described in claim 1, wherein these shields are screw twisteds.

4. discharge gas processing system as described in claim 1, wherein the flow regulator is located in the upper of the injector Trip.

5. discharge gas processing system as described in claim 1, wherein the flow regulator be suspended in the exhaust manifolds with The identical side of the injector.

6. discharge gas processing system as described in claim 1, wherein the flow regulator be suspended in the exhaust manifolds with The opposite side of the injector.

7. discharge gas processing system as described in claim 1, wherein these shields are to be staggered in the one side of the twisted plate 's.

8. discharge gas processing system as described in claim 1, wherein these shields include respectively different height.

9. a kind of discharge gas processing system for reducing the emission of engine, the discharge gas processing system include：

Exhaust gas treatment device；

Exhaust manifolds, the exhaust manifolds are adapted for exhaust stream being supplied to the exhaust gas treatment device from the engine；

Sensor, the sensor are connected with the exhaust manifolds；

Flow regulator, the flow regulator are located in adjacent to the sensor in the exhaust manifolds,

The discharge gas processing system is characterized in that,

The flow regulator includes the plate having a first end and a second end, which is fixed to the exhaust manifolds For opposite side the plate to be suspended in the exhaust manifolds, which includes multiple shields, these shields are with towards the non-of the sensor Unified direction guides the exhaust stream.

10. discharge gas processing system as claimed in claim 9, wherein the plate is bending.

11. discharge gas processing system as claimed in claim 9, wherein these shields are the contact pin shapes by being pierced by from the plate At.

12. discharge gas processing system as claimed in claim 9, wherein these shields are screw twisteds.

13. discharge gas processing system as claimed in claim 9, wherein the flow regulator is located in the upper of the sensor Trip.

14. discharge gas processing system as claimed in claim 9, wherein the flow regulator is suspended in the exhaust manifolds Side identical with the sensor.

15. discharge gas processing system as claimed in claim 9, wherein the flow regulator is suspended in the exhaust manifolds The side opposite with the sensor.

16. discharge gas processing system as claimed in claim 9, wherein these shields are staggered in the one side of the plate.

17. discharge gas processing system as claimed in claim 9, wherein these shields include respectively different height.

18. a kind of discharge gas processing system for reducing the emission of engine, the discharge gas processing system include：

Exhaust gas treatment device；

Exhaust manifolds, the exhaust manifolds are adapted to exhaust stream being supplied to the exhaust gas treatment device, the exhaust from the engine Conduit includes aperture；

Injector, the injector are used to reagent being ejected through the aperture and enter the exhaust stream；

Flow regulator, the flow regulator are located in adjacent to the injector in the exhaust manifolds, which includes more A shield, these shields guide the exhaust stream with the direction towards or away from the injector,

The discharge gas processing system is characterized in that,

The flow regulator includes the twisted plate having a first end and a second end, which is fixed to the exhaust and leads The opposite side of pipe is the twisted plate to be suspended in the exhaust manifolds, and these shields extend out from the twisted plate.

19. discharge gas processing system as claimed in claim 18, wherein these shields are to be staggered in the one side of the plate 's.

20. discharge gas processing system as claimed in claim 18, wherein these shields are connect by what is be pierced by from the twisted plate What piece was formed.

21. discharge gas processing system as claimed in claim 18, wherein these shields are screw twisteds.

22. discharge gas processing system as claimed in claim 18, wherein the flow regulator is located in the upper of the injector Trip.

23. discharge gas processing system as claimed in claim 18, wherein the flow regulator is suspended in the exhaust manifolds Side identical with the injector.

24. discharge gas processing system as claimed in claim 18, wherein the flow regulator is suspended in the exhaust manifolds The side opposite with the injector.

25. discharge gas processing system as claimed in claim 18, wherein these shields include respectively different height.