KR20110009685A - Exhaust element comprising a static means for mixing an additive into the exhaust gases - Google Patents

Abstract

The present invention is included in a line for discharging a gas of a motor vehicle having a combustion engine 1 in which a fluid composed of exhaust gas and an additive to the exhaust gas flows through the interior, and the exhaust gas and the additive It relates to an exhaust element 4 having static means 6 mounted inside the exhaust device for mixing. The fixed means 6 for mixing these exhaust gases with this additive has at least one screw having an axis extending in a direction forming a constant angle with the fluid flow direction D penetrating the exhaust device 4. A hull (helicoid) 61.

Description

EXHAUST ELEMENT COMPRISING A STATIC MEANS FOR MIXING AN ADDITIVE INTO THE EXHAUST GASES}

The present invention relates to an exhaust device installed in a line for discharging gases discharged from a motor vehicle having a combustion engine.

FIELD OF THE INVENTION The present invention relates to the field of the automotive industry, and more particularly to the field of the manufacture of a plant configured to reliably release gases from the combustion of fuel inside a combustion engine of a motor vehicle.

Such a device takes the form of an exhaust line connected to such a combustion engine on the one hand according to the flow direction of the exhaust gas of this exhaust line, on the other hand, comprises a series of exhaust elements, and on the other hand, opens to the atmosphere.

In particular, among these exhaust elements, the exhaust line comprises one or more devices for the physical and / or chemical treatment of the exhaust gas.

Such a device consists of a catalytic converter which may take the form of a catalytic converter (especially in the form of an SCR) for reducing nitrogen oxides (NOx) and has at least a means of treatment of gases configured to ensure this reduction. Such catalytic converters find particular application when cleaning of exhaust gases resulting from the combustion of diesel fuel is required.

The reduction of these exhaust gases inside such catalytic converter is greatly improved when these exhaust gases are mixed with urea containing additives prior to the introduction of the exhaust gases into such catalytic converter. In fact, upon ingress into hot exhaust gases (especially after evaporation of aqueous urea solution), urea produces its chemical conversion into ammonia (NH 3), which constitutes a powerful abatement agent. As such, the exhaust gas is reduced within the catalytic converter and in the presence of such ammonia to separate hydrogen (H 2) and nitrogen (N 2) at the outlet of the catalytic converter.

In this respect, the more uniform the mixture of the exhaust gas and the additive, the more effective this reduction of nitrogen oxides is.

In order to improve the uniformity of the mixture, it is common to use a mixer fixedly installed inside the exhaust device (usually the exhaust conduit) and upstream of the gas treatment means.

As described in WO9300990, such a mixer is arranged along a plurality of rows perpendicular to the axis of symmetry of the exhaust device, while having a plurality of deflections in the same direction within the same row and in the opposite direction of two adjacent rows. It takes the form of elements.

EP-1.514.591 also discloses an exhaust apparatus having a plurality of zigzags in the form of a curved strip of metal sheet extending from the perimeter of the exhaust element inside a fixed mixer.

These devices, of course, improve the uniformity of the mixture downstream of the mixer but have the problem of bringing upstream of this mixer a significant back pressure that is detrimental to the flow of gases in the exhaust line and its treatment and discharge.

It is an object of the present invention to provide an exhaust device which can solve the problems of the prior art device.

The present invention for achieving the above object is included in a line for discharging gas from a motor vehicle having a combustion engine in which a fluid consisting of exhaust gas flows therein and is mounted therein for mixing such exhaust gas and such additives. To an exhaust device with static means. The exhaust device comprises at least one helicoid having an axis in which a fixed means for mixing the exhaust gas and the additive extends in a direction forming a constant angle with the direction of fluid flow through the exhaust device. It is done.

An additional feature relates to the fact that the direction of extension of the helix axis forms an angle of 0 to 30 °, such as the direction of fluid flow through the exhaust.

According to another feature, the mixer comprises a plurality of helices each having an axis extending through the exhaust device in a direction in which the flow direction of the fluid forms a certain angle, in particular between 0 and 30 °, The extending direction extends in particular in the direction forming the angle between 0 and 30 °.

According to an additional feature, the two overlapping helices have the same or preferably opposite directions of rotation.

According to an additional feature, the mixer comprises a plurality of helices, which are classified into the same group in at least one set comprising at least two helices, preferably with the same direction of rotation.

According to another feature, the mixer comprises a plate arranged parallel to the direction of fluid flow through the exhaust device, on the other hand, at least one spiral or at least two pieces extending downstream of the plate. At least one module comprising a set of hulls.

Indeed, this mixer comprises at least two helices, each of which is set with a plate, while on the other hand it is assembled two by one in particular vertically via an assembly means comprised by at least one plate of at least one such module. It includes a plurality of modules.

Finally, such a module consists of one part, in particular a metal part, preferably manufactured by cutting out, boring, and in particular by folding.

Indeed, the exhaust device consists of an exhaust conduit comprising means for mixing the additives with the exhaust gas therein or includes means for mixing the additives with the exhaust gas therein and the physical and downstream of the mixture downstream of the mixer. And / or physical and / or chemical treatment of the exhaust gas comprising chemical treatment means.

The invention also relates to an exhaust line with such an exhaust device.

It is an advantage of the present invention that the exhaust device comprises a fixed mixer consisting of at least one helix installed inside the exhaust device and mixing additives and exhaust gas. By such a spiral body, the vortex motion which improves the uniformity of a mixture can be effectively given to a fluid. Another advantage of such a spiral is that the fluid downstream of the spiral has a flow such that the back pressure generated by the mixture of additives / exhaust gases is considerably lower than that generated by conventional devices.

In addition, such a mixer may also comprise a plurality of helixes which are effectively effectively arranged inside the exhaust device to match the size of the exhaust device and / or the structure which can effectively optimize the fluid flow downstream of this mixture means. have.

In addition, the number of spirals, their positioning relative to each other, can effectively achieve good results of uniformity of mixing and weakness of the back pressure downstream of the mixer (and in terms of coordination between the back pressure and loss of shear). These characteristics (rotational direction, length, pitch, diameter, and axial direction) can be easily configured.

In this respect, it should be noted that when such a mixer preferably comprises two paired helices but at least one paired helices, good results are obtained.

As an additional feature, the mixer is installed inside an exhaust conduit consisting of an exhaust conduit or a gas treatment device, in particular a catalytic converter. In this embodiment, the mixer can be positioned in an appropriate manner in the exhaust line with respect to the additive supply means and with respect to the exhaust gas treatment means.

Finally, such mixers can be produced from at least one metal sheet, in particular by cutting, boring and in particular by folding. This makes it possible to effectively provide a fixed mixer which is particularly effective for reducing manufacturing costs in particular.

Other objects and advantages of the invention will be apparent from the following description which refers only to the described embodiments by way of example only and not of limitation.

Understanding of the above description will be facilitated with reference to the accompanying drawings, in which:
1 is a schematic view of an exhaust line with an exhaust device according to the invention;
FIG. 2 is a longitudinal view of a schematic partial cross section of an exhaust device consisting of an exhaust conduit and containing an additive and exhaust gas mixing means (mixer) therein;
3 is a schematic detailed view of this mixer;
4a and 4b are schematic detailed views respectively displaying each of the two modules constituting such a mixer;
5a to 5d are schematic detailed views corresponding to a first embodiment in which such a mixer is installed in the exhaust device of FIG. 2;
6a to 6c are schematic detailed views corresponding to the first embodiment in which such a mixer is installed in the exhaust device of FIG.

The present invention relates to the field of the automobile industry, and more particularly to the field of the manufacture of a plant configured to reliably discharge gases generated from the combustion of fuel inside a combustion engine 1 of a motor vehicle.

This arrangement is in the form of an exhaust line 2, which is connected to the engine 1 and has a plurality of exhaust devices 3, 4 connected to one another along the exhaust line 2.

In particular, as shown in FIG. 1, this exhaust line 2 comprises at least one exhaust device 3 composed of a device for ensuring the physical and / or chemical treatment of gases resulting from fuel combustion of the engine 1. can do.

This treatment device 3 may be composed of a particle trap 31 (usually called a FAP) installed downstream of the engine 1.

This treatment device 3 may also consist of a catalytic converter 32 arranged downstream of the engine 1. According to the first embodiment corresponding to the standard structure of the exhaust line 2 shown in FIG. 1, the catalytic converter 32 may be installed downstream of the particle trap 31 described above. However, according to another embodiment, not shown, this catalytic converter 32 is also a more complicated exhaust device 3 (commonly referred to) having a particle trap 31 and a catalytic converter 32 of the type described above. It can be integrated into.

In practice, it consists of a catalytic converter 32, in particular and a catalytic converter for treating nitrogen oxides (NOx) contained in at least exhaust gas.

Such catalytic converters 32 for the treatment of nitrogen oxides consist of catalytic converters (commonly referred to as NOx traps) for trapping these nitrogen oxides or for example three-way catalytic converters of the TWC type or selective catalytic reduction (SCR) type. It can be composed of a catalytic converter.

In a special case of the catalytic converter 32 for reducing nitrogen oxides, the catalytic converter 32 is configured to reliably reduce nitrogen oxides contained in these exhaust gases therein (especially ceramic or similar means). It includes.

In this respect, it should be appreciated that the catalytic reduction of the nitrogen oxides contained in the exhaust gas can be promoted if these gases contain a reducing agent.

The presence of a reducing agent in these gases is within the exhaust line 2 and the precursor or reducing agent of such reducing agent which is converted to such reducing agent upstream of the treatment means is inside the exhaust line 2 and the catalytic converter 32 ) Can be identified by introducing upstream.

For this purpose, the exhaust line 2 is provided with means 5 downstream of the particle trap 31 and provided upstream of the catalytic converter 32, with the exhaust line 2 having a catalyst in the catalytic converter 32. It is configured to introduce additives (especially by injection, more particularly after pulverization or evaporation) which must be added to the exhaust gas so that the fluid is treated by abatement.

The additive thus introduced consists of a reducing agent or a precursor of the reducing agent.

Indeed, and in accordance with a preferred embodiment, this additive may consist of a solution (especially an aqueous solution) which is based on urea and has a small amount of urea, especially known under the name AdBlue (precursor of a reducing agent). This solution undergoes chemical conversion (thermolysis, hydrolysis) to be at least in the form of ammonia (NH 3) in the exhaust line 2, which is mixed with the exhaust gas inside the fluid to be treated to form a reducing agent.

The efficiency of catalyst reduction of the nitrogen oxides contained in the exhaust gas increases with an increase in the uniformity of the fluid treated by the catalytic converter 32.

In order to homogenize this fluid, the exhaust line 2 also has a fixed means 6 for mixing the additive and the exhaust gas, which is referred to as a mixer 6 for convenience in the following description.

In this case, the mixer 6 may contain a reducing agent (if introduced after conversion into an additive consisting of such a reducing agent or a precursor of such reducing agent introduced into the exhaust line 2) and / or of such reducing agent. It is configured to mix the exhaust gas with an additive which may consist of a precursor (in the case of introducing an additive consisting of a reducing agent precursor).

Indeed, as shown in the accompanying figures, the mixer 6 is installed inside along the exhaust line 2 between the means for treating the fluid and the means 5 for introducing the additive.

In this respect, according to a first embodiment, not shown, this mixer 6 is internal to the exhaust device 3 which consists of a physical and / or chemical treatment device 3 of the exhaust gas contained in the exhaust line 2. Can be installed on

The treatment device 3 comprises means 6 for mixing additives with exhaust gas therein and means for physically and / or chemically treating the mixed fluid downstream of the mixer 6.

Preferably, the exhaust gas treatment device 3 is, in this case, constituted by a catalytic converter 32 for catalytic reduction of nitrogen oxides contained in the exhaust gas or in the above-described form including such a catalytic converter 32. (Cata-FAP), a more complicated processing device 3 is constructed.

However, according to a preferred embodiment of the invention, the means 6 for mixing the additive with the exhaust gas is mounted inside the exhaust device 4 consisting of the exhaust conduit 41.

As shown in the accompanying figures, this exhaust device 4 preferably consists of an exhaust conduit 41 for connecting the particle trap 31 to the catalytic converter 32.

Indeed, as shown in FIGS. 5A-5D and 6A-6C, such conduits 41 may comprise two portions of conduits 41 in which at least one portion 411 of which receives mixer 6 therein ( 411 and 412, preferably. In this case, before the connection of this part 411 of the conduit 41 to the other part 412 of this conduit 41 (in particular complemented by an integral connection, for example by welding), the mixer 6 is connected to the open end. Is introduced into this portion 411 of the conduit 41.

Regardless of the nature (such as treatment device 3 or conduit 41) and / or structure of these exhaust devices 3, 4, the latter also allows the mixer 6 inside the exhaust devices 3, 4. Means for receiving.

In fact, as shown in FIGS. 5A-5D and 6A-6C, this receiving means 7 is preferably composed of a special structure of the exhaust devices 3, 4, in particular such exhaust devices 3, 4. It is produced by the modification of, and consists in particular of the open end of the part 411 of the conduit 41 which constitutes such an exhaust device 4.

According to the invention, the means 6 for mixing the additive and the exhaust gas consist of at least one spiral 61.

Such a spiral 61 is characterized by at least a pitch, a length, a diameter, a thickness, a width, an axis in which the spiral extends, and a direction of rotation.

In this respect, it should be appreciated that the width of this spiral 61 may be constant in the direction of fluid flow D through the exhaust devices 3, 4. However, good results have been obtained for the spiral 61 in which the width increases or preferably decreases in the direction D of the fluid flowing through the exhaust devices 3, 4.

Indeed, according to another feature of this helix 61, the latter has a width suitable for the structure of the exhaust devices 3, 4 for receiving at least one such helix 61. According to this embodiment, at least one such spiral body 61 is particularly suitable for this structure (particularly in cross-sections of such exhaust devices 3, 4) in order to occupy the entire internal volume of the exhaust devices 3, 4. ) Width can be adjusted.

In addition, and according to another feature, the spiral body 61 has an axis extending through the exhaust apparatuses 3 and 4 in a direction in which the fluid flows in a direction D and a direction angle is formed.

In this respect, it should be noted that the direction of extension of the axis of this spiral 61 forms an angle α between 0 and 30 ° with the direction D in which fluid flows through the exhaust devices 3, 4.

According to a particular, non-illustrated embodiment of the invention, the mixer 6 may consist of a single spiral 61 installed inside the exhaust conduit 41, the axis of which is parallel to the axis of this conduit 41 and In particular.

However, and according to a preferred embodiment of the present invention, this mixer 6 actually comprises a plurality of helixes 61.

By this embodiment the mixer 6 can be effectively adapted to the cross sections of the exhaust devices 3, 4 and / or can be configured to improve the quality of the homogenization of the fluid at the outlet of the mixer 6.

By way of example only, this mixer 6):

Two helices 61 for the exhaust device 3, 4 having a substantially rectangular cross section;

Three helices 61 for the exhaust device 3, 4 having a substantially triangular cross section;

Four helices 61 for the exhaust devices 3, 4 having a substantially square (FIG. 6C) or circular (FIG. 5D) cross section.

According to another feature of the invention, each of these helices 61 extends in the direction of extending the axis of the other helix or helixes 61 of the mixer 6 and in a direction forming a certain angle α '. On the other hand, it has an axis extending through the exhaust apparatuses 3 and 4 in the direction in which the fluid flows and the direction D forms a predetermined angle α.

In this respect, it should be noted that the direction of extension of the axis of the spiral 61 actually forms an angle α 'between 0 and 30 ° with the direction of extension of the axis of the other spiral or helixes 61.

In a similar case, as described above, the direction of extension of the axis of this spiral body 61 is also a constant angle α between 0 and 30 ° and the flow direction D of the fluid flowing through the exhaust devices 3, 4. ) Can be formed.

In certain embodiments (shown in the accompanying figures) the angles α and α 'are zero, so that the axis of the helix 61 is the direction of extension of the axis of the other helixes or helices 61 of the mixer 6 and the It is configured to be parallel to the direction D in which the fluid flows through the exhaust devices 3, 4. In this case, the axes of extension of the spirals 61 are parallel between them.

However, according to another structure not shown, these spirals 61 are arranged such that their extension axes diverge or converge in the flow direction D of the fluid passing through the exhaust devices 3, 4. Can be deployed.

As described above, these spirals 61 increase or decrease constantly and / or conform to the structure of the exhaust devices 3 and 4 in the flow direction D of the fluid passing through the exhaust devices 3 and 4. Has a width.

This feature is combined with the feature of the direction of extension of the axes of these spirals 61 (in particular in a convergent or expanding manner) to occupy in particular the entire internal volume of such an exhaust device 3, 4. It is possible to effectively combine these spiral bodies 61 in the structure of 3, 4) (particularly in the cross section of the exhaust device).

According to an additional feature of the invention, the axes of these helices 61 are in particular arranged in a matrix which is particularly regular with respect to the structure (rectangle, triangle, circle, or square) of the cross section of this exhaust device 3, 4. As a matrix (rectangular, triangular, circular, or square). According to this embodiment, with respect to the structure of the exhaust devices 3 and 4, it is possible to suitably position and distribute these spiral bodies 61 inside the exhaust devices 3 and 4 according to the structure.

As described above, each helix 61 has a direction of rotation. In this aspect, according to an additional feature of the present invention, even two immediately adjacent overlapping helices 61 and even the entire helixes 61 of the mixer 6 may have the same direction of rotation.

This embodiment is particularly effective when the fluid generates longitudinal turbulent motion (vortex) upstream of the mixer 6.

However, and according to a preferred embodiment of the invention (FIGS. 3, 5d, 6c), these immediately overlapping spirals 61 preferably have opposite directions of rotation (helical bodies rotating counterclockwise). By this embodiment a fluid to be treated which is suitably mixed can be obtained.

Another feature of the invention is that at least one set 611 of the inventive mixer 6 comprises a plurality of helices 61 and these helices 61 comprise at least two helices 61. 612), and are distinguished from within.

In this respect, the helices 61 of the same set 611; 612 of the helices 61 are optionally opposite (reverse rotating helices) or (preferably) identical (Figs. 3, 4a, 4b, 5d). , 6c) should have a direction of rotation.

A particular embodiment, not shown, comprises a set of at least two helicoids 61, which may in particular consist of a mixer 6 suitable for an exhaust device 4 having a rectangular or elliptical cross section.

However, and in accordance with a preferred embodiment of the present invention, the mixer 6 comprises at least one set 611 (plural sets of two (or more) spirals 61 aligned in the direction of the first set). At least two (or more) helicoids 61, including, preferably parallel), aligned in the second set of directions to form an angle (preferably right angle) with the first set of directions. Also includes at least another set 612 (a plurality of other sets, preferably parallel).

In this respect, the number of these sets 611; 612, the number of helices 61 constituting such sets 611; 612, and the arrangement and orientation of these sets 611; In order to optimize the filling of the surface imparted by the cross section of 4) it is determined in accordance with the structure of the exhaust devices 3, 4 containing the mixer 6.

According to a preferred embodiment of the invention (FIGS. 3 to 6c), the mixer 6, in particular two sets of verticals 611 and 612, of the spiral 61, each comprising a pair of spirals 61. To include them. In this embodiment, two helices 61 of the same set 611; 612 have the same direction of rotation, and two immediately overlapping helices 61 of the two different sets 611; 612 have the same direction of rotation. 3 to 6C, but may preferably have a reverse rotation direction.

Such a mixer 6 with four helixes 61 is composed of an exhaust gas treatment device 3 as described above or manufactured on the basis of a conventional (and most commonly used) design and has a circular cross section (FIG. 2). It may be arranged inside the exhaust device (3, 4) consisting of the exhaust conduit (4) having from to 6c.

In the latter case, the axes of the four helices 61 are preferably arranged according to a square matrix compared to the rounded structure of the cross section of the exhaust conduit 41.

According to the first embodiment of FIGS. 5A-5D, these four helices 61 are installed inside a portion 411 having a round cross section of the exhaust conduit 41.

However, and in accordance with a preferred embodiment of the invention shown in FIGS. 6A-6C, four helices 61 have a specific portion 411 ′ having a square cross section defined at the level of the exhaust conduit 41 having a round cross section. It is installed inside. This embodiment increases the efficiency of the mixer 6 and can reduce the cross-sectional surface of the conduit 41 which is slightly (and rarely) affected by the action of the spirals 61 in proportion to the round cross section. have.

In practice, this portion 411 ′ having a square cross section can be formed by deformation of the exhaust conduit 41 having a round cross section, in particular by expansion.

According to another feature of the invention, these helixes 61 have an inner diameter (part having a rounded cross section of the conduit 4, 411) or part of an exhaust conduit 4 which receives these helices 61. 411, 411 ') having a diameter of 25-40% (preferably 35% range) of the largest cross section (part 411' with square cross section of conduit 4).

The preferred embodiment has been described above with respect to a mixer 6 comprising two sets 611, 612 each consisting of two helices 61. The present invention, however, is in no case limited to this structure.

Furthermore, and in accordance with another embodiment not shown, the mixer 6 also comprises at least one set consisting of two or more spirals 61 (particularly three, four or more) arranged in alignment ( 611; 612. Another embodiment may also consist of a mixer 6 comprising a plurality of sets comprising at least a different number of helices 61 in certain cases.

As such, the mixer 6 comprises at least one set 611 (plural sets, preferably parallel) comprising three, four or more helices 61 aligned in the direction of the first set. At least another set 612 of at least two (or more) spirals 61 aligned in the second set of directions to form an angle (preferably right angle) with the first set of directions; It is contemplated to include on the other hand (a plurality of different sets, preferably parallel).

An additional feature is that these spirals 61 have a length between 60 and 100 mm, preferably in the range of 80 mm, in particular 82 mm.

According to another feature of the invention, the fixed means 6 for mixing the additive and the exhaust gas comprise plates 621; 622 each facing parallel to the direction of fluid flow D passing through the exhaust device. On the other hand, it includes at least one helix 61 or at least one helix 62 which extends downstream of the plates 621; 622.

In this aspect, this plate 621; 622 has two longitudinal sides, in particular at least one spiral 61 from one of said longitudinal sides (especially the downstream longitudinal side) and from its extension. Extends or extends the helix 61 of the set 611; 612 of the helix 61 that the module 62 includes.

Indeed, and according to a first embodiment not shown, this mixer 6 comprises one module 62 comprising a plate 621 and a spiral 61 or a set of at least two spirals 611. It may include.

However, and according to a preferred embodiment, the mixer 6 comprises a plate 621; 622 and at least two sets of spirals 61, 611; 612, respectively, on the other hand, at least one. It comprises a plurality of modules 62 assembled two by two in particular vertically via assembly means 63 included in at least one plate 62 of such a module 62.

In this aspect, the assembling means 63 is composed of interlocking means 631 installed on the plate 621, while on the other hand is composed of auxiliary interlocking means 632 installed on the other plate 622. You need to know that.

As shown in FIGS. 4A and 4B, this interlocking means 631 consists of a notch formed in an upstream portion of the plate 621 (especially at a level upstream of the longitudinal side of the plate 621), The interlocking means 632 consists of another notch formed corresponding to the downstream portion of the other plate 622 (in particular at a level downstream of the longitudinal side of the plate 622).

3, 5d, and 6c, the spiral 61 of the set of helices 611 is preferably inserted between the two helices 61 of another set of helices 612, but the This assembly is done such that it is horizontally offset with respect to the alignment direction of the two helices 61 of the other set 612.

Another feature is that at at least one level of the horizontal edges of the plates 621; 622 of the module 62, a wing 62 in which the module 62 is located at the extension of the plates 621; 641; 642).

In the particular case of the mixer 6 comprising one module 62, two horizontal edges of this plate 621 extend to these wings 641, 641 ′ which actually extend horizontally with respect to this plate 621. Can be extended by. These wings 641; 641 ′ are in particular accommodated by the receiving means 7 contained in the exhaust device 3, 4, so as to mount the mixer 6 inside the exhaust device 3, 4. ) Effectively

In the case of a mixer 6 comprising a plurality of modules 62, each of these modules 62 includes: the plate 621 at at least one level of the horizontal edges of the plates 621; 622 of the module 62; A wing 641 located in the extension of 622 and directed in the direction of a wing 642; 641, which is integrally formed by welding, as another wing of the plate 622; 621, which another module 62 includes; 642).

3, 4a, 4b, 5d, and 6c, the plates 621; 622 of each module 62 have an extension of this plate 621; 622 at the level of the two horizontal edges. Wings 641, 641 '; 642, 642' which are positioned and directed in the direction of the wings 641, 641 '; 642, 642', which may include other plates 622; 621, and in particular may be integrally formed by welding. ).

In this respect, the wings 641, 641 ′; 642, 642 ′ are actually accommodated by the receiving means 7 which these exhaust devices 3, 4 comprise, so that the mixers inside the exhaust devices 3, 4 are particularly effective. It should be understood that the means 8 for mounting (6) are effectively configured.

According to another feature of the present invention, the module 62 as described above is preferably composed of one part, in particular a metal part, which is produced supplemented by cutting, boring, in particular folding.

The following parts are defined at this single part level:

Plates 621; 622;

At least one helix 61 or a set 611; 612 of at least two helices 61; And,

At least one wing 641, 641 ′; 642, 642 ′, in which this module 62 comprises assembly means 63, 631, 632.

As described above, the exhaust device 3 comprising a mixer 6 having the above-described features physically mixes the mixture 6 with the means 6 for mixing additives and exhaust gas therein and downstream of the mixer 6. And / or a physical and / or chemical treatment apparatus 3 for exhaust gas comprising means for chemically treating.

This processing apparatus 3,

A catalytic converter 32, for example a three-way catalytic converter in the form of a TWC or also an SCR (optional), for example for the treatment of nitrogen oxides (NOx) contained in exhaust gases, in particular for the catalytic reduction of said nitrogen oxides (NOx). Catalytic converter) type;

Or a more complicated exhaust device 3 (commonly called cata-FAP) incorporating such a catalytic converter 32 and a particle trap 31 of the type described above.

However, and according to a preferred embodiment, the exhaust device 4 according to the invention preferably comprises an exhaust conduit 41 having therein means 6 for mixing additives with the exhaust gas having the above-described features. It is composed.

Finally, the invention also relates to a gas exhaust line 2 of a motor vehicle provided with a combustion engine 1, which is to be added to the exhaust gas on the one hand, depending on the flowing direction of the gas in the exhaust line 2. Means 5 for introducing the additive into the exhaust line 2, on the other hand fixed means 6 for mixing the additive with the exhaust gas, and on the other hand, physical and / or chemical treatment means of the mixture. Include.

According to the invention, the exhaust line 2 comprises the exhaust devices 3, 4 having the above-mentioned characteristics and comprising the means 6 for mixing the additive with the exhaust gas. The mixer 6 comprises means 5 for introducing additives into the line 2 and means for treating the mixture (especially if the exhaust device 3 consists of such a device 3, the physical properties of this mixture). And / or provided internally by the apparatus 3 for chemical treatment.

The invention will find application in the field of manufacturing facilities for discharging the gas obtained by the engine 1 of a motor vehicle and from the combustion of fuel, in particular diesel fuel, inside the engine 1.

Example embodiment ( Exemplary Embodiment )

Engine power at full load: 600kg / h at 600 ° C

Mixer (6):

Two pairs of helices 611; 612;

Two helices 61 of the same pair in the same direction of rotation;

Two helixes 61 of two different pairs in opposite directions of rotation (reverse helixes);

Pitch and length of the spirals: 82 mm

The diameter of the spirals: 21 mm

Exhaust: conduit with an internal diameter of 60 mm;

Back pressure generated downstream of the mixer: 33 mbar.

Claims (17)

An exhaust device (3; 4) included in an exhaust line (2) for discharging gas of a motor vehicle having a combustion engine (1) in which fluid composed of exhaust gas and additives flows through the exhaust device (3), A static means mounted inside the exhaust device for mixing the exhaust gas and the additive, wherein the fixing means for mixing the exhaust gas and the additive has a set angle with the fluid flow direction (D) passing through the exhaust device. and at least one spiral body (61) having an axis extending in the direction of forming (α). The method of claim 1,
The spiral body (61) is characterized in that the width of the fluid flowing through the exhaust device in the exhaust direction (D) characterized in that the exhaust device. The method of claim 1,
The spiral body (61) is characterized in that the exhaust device characterized in that the width decreases in the flow direction (D) of the fluid passing through the exhaust device. 4. The method according to any one of claims 1 to 3,
And an angle [alpha] between the fluid flow direction D passing through the exhaust device and the extending direction of the spiral axis is between 0 and 30 degrees. The method according to any one of claims 1 to 4,
The mixer 6 comprises a plurality of helices 61, each helix 61 on the one hand extending the direction of the axis of the other helix 61 and the set angle α ′, in particular 0 to 30 °. Extending in a direction forming an angle therebetween and on the other hand having an axis extending in the direction of forming a flow direction D of the fluid passing through the exhaust device and a set angle α, in particular an angle between 0 and 30 °. Characterized in that the exhaust system. The method of claim 5, wherein
And the spiral bodies (61) are arranged such that the extended shafts diverge in the flow direction of the fluid passing through the exhaust device. The method of claim 5, wherein
And said spiral bodies (61) are arranged such that extension axes converge in the direction of flow of fluid passing through said exhaust device. 8. The method according to any one of claims 5 to 7,
The axes of the spirals (61) are arranged according to a matrix, in particular a regular matrix, with respect to the cross-sectional structure of the exhaust device. The method according to any one of claims 5 to 8,
Exhaust device, characterized in that two adjacent overlapping spiral bodies (61) have the same direction of rotation. The method according to any one of claims 5 to 8,
Exhaust device, characterized in that two adjacent overlapping spiral bodies (61) have opposite directions of rotation. The method according to any one of claims 1 to 10,
The mixer 6 has a plurality of helices 61 and these helices 61 are preferably one or more sets 611 and 612 comprising two or more helices 61 having the same direction of rotation. Exhaust system characterized in that a group. The method according to any one of claims 1 to 11,
The mixer 6 is comprised of a plate 621; 622 parallel to the fluid flow direction D through the exhaust device and one or more spirals 61 or two extending downstream of the plate 621; 622. And at least one module (62) comprising at least one set (611; 612) of helixes (61). The method of claim 12,
The mixer 6 comprises a plurality of modules 62, each module 62 comprising a plate 621; 622 and a set of two or more helices 61, 611; 612. Wherein the module (62) is assembled two by two, in particular vertically, via assembly means (63) included in one or more plates (621; 622) of one or more modules (62). The method of claim 13,
The module 62 includes wings 641, 641 '; 642, 642' at at least one position of the horizontal edges of the plates 621; 622, and the wings 641, 641 '; 642, 642'. Is located in the extension of the plates 621; 622 and is directed in the direction of the other wings 641, 641 '; 642, 642' that the plates 622; 621 of the other module 62 contain, in particular by welding. , Exhaust device characterized in that it is connected to the other wings (641, 641 '; 642, 642'). The method according to any one of claims 12 to 14,
Said module (62) is preferably formed by cutting, boring, and in particular consists of one part, in particular a metal part, which is complemented by folding. The method according to any one of claims 1 to 15,
Said exhaust device comprises means (7) for receiving said mixer (6). The method according to any one of claims 1 to 16,
The exhaust device consists of an exhaust conduit 41 comprising means 6 for mixing the additive with the exhaust gas or comprises means 6 for mixing the additive with the exhaust gas and of the mixer 6. An exhaust device, characterized in that it consists of a physical and / or chemical treatment device (3) of the exhaust gas downstream comprising physical and / or chemical treatment means of the mixture.

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