MIXER FOR EXHAUST AFTERTREATMENT SYSTEM

TECHNICAL FIELD

The present application relates generally to a mixer for exhaust aftertreatment systems for an internal combustion engine.

BACKGROUND

The exhaust of internal combustion engines, such as diesel engines, includes nitrogen oxide (NO_X) compounds. It is required to reduce NO_Xemissions to comply with environmental regulations, for example. To reduce NO_Xemissions, a treatment fluid may be dosed into the exhaust by a doser assembly within an aftertreatment system. The treatment fluid facilitates conversion of a portion of the exhaust into non-NO_Xemissions, such as nitrogen (N₂), carbon dioxide (CO₂), and water (H₂O), thereby reducing NO_Xemissions. These aftertreatment systems may include a mixer that facilitates mixing of the treatment fluid and the exhaust.

SUMMARY

In one embodiment, a flow device for a mixer of an exhaust aftertreatment system. The flow device includes a plate and a plurality of conduits coupled to the plate. Each of the conduits includes a first sidewall extending outward of the plate, a second sidewall extending outward of the plate and opposing the first sidewall, a main wall extending from the plate and between the first sidewall and the second sidewall, a conduit inlet coplanar with the plate and that receives exhaust, and a conduit outlet forming an angle between 35 degrees and 145 degrees, inclusive, with the plate. The conduit outlet releases the exhaust received from the conduit inlet.

In another embodiment, a mixer for an exhaust aftertreatment system. The mixer includes an inlet that receives exhaust from an exhaust conduit, an outlet that provides a mixture of the exhaust and a treatment fluid, and a first flow device that receives the exhaust from the inlet. The first flow device includes a plurality of main vanes and a plurality of main vane apertures interspaced between the main vanes. Each of the main vane apertures receives the exhaust and cooperates with at least one of the main vanes to facilitate swirling of the exhaust. The mixer further includes a second flow device disposed downstream of the first flow device and that receives the exhaust from the first flow device. The second flow device includes a plate and a plurality of conduits coupled to the plate. Each of the conduits includes a first sidewall extending outward of the plate, a second sidewall extending outward of the plate and opposing the first sidewall, a main wall extending from the plate between the first sidewall and the second sidewall, a conduit inlet coplanar with the plate and that receives the exhaust, and a conduit outlet forming an angle between 35 degrees and 145 degrees, inclusive, with the plate. The conduit outlet releases the exhaust received from the conduit inlet. A conduit outlet of at least one of the conduits has a length and a height. A ratio of the length to the height is between 1.5 and 5, inclusive. The mixer further includes a third flow device disposed downstream of the second flow device and that receives the exhaust and the treatment fluid from the second flow device. The third flow device includes a plurality of peripheral apertures and a main aperture. A distance between a center of the third flow device and each of the peripheral apertures is 90% to 98%, inclusive, of a radius of the third flow device.

BRIEF DESCRIPTION OF THE DRAWINGS

The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the disclosure will become apparent from the description, the drawings, and the claims, in which:

FIG. 1 is a block schematic diagram of an example exhaust aftertreatment system;

FIG. 2 is a schematic of an example mixer of the exhaust aftertreatment system;

FIG. 3 is a schematic of another example mixer;

FIG. 4 is a cross-sectional view of yet another example mixer;

FIG. 5 is a perspective cross-sectional view of the mixer of FIG. 4 that includes a first flow device, a second flow device, and a third flow device;

FIG. 6 is a perspective view of an example first flow device of FIG. 5;

FIG. 7 is a rear view of the first flow device of FIG. 6;

FIG. 8 is a side view of the first flow device of FIGS. 6 and 7;

FIG. 9 is a rear view of an example third flow device overlapping an example second flow device;

FIG. 10 is rear view of another example third flow device overlapping the example second flow device;

FIG. 11 is a rear view of an example second flow device of FIGS. 9 and 10;

FIG. 12 is a rear view of another example second flow device;

FIG. 13 is a perspective view of the second flow device of FIG. 12;

FIG. 14 is a rear view of yet another example second flow device;

FIG. 15 is a perspective view of a portion of the example second flow device of FIG. 14;

FIG. 16 is a cross-sectional view of the portion of the example second flow device of FIG. 15;

FIG. 17 is a perspective view of a portion of yet another example second flow device;

FIG. 18 is a cross-sectional view of the portion of the example second flow device of FIG. 17;

FIG. 19 is a perspective view of a portion of yet another example second flow device;

FIGS. 20 and 21 are perspective views of portions of yet other various examples of the second flow device;

FIGS. 22-26 are side views of various examples of the second flow device;

FIG. 27 is a cross-sectional view of yet another example mixer that includes an example first flow device, an example second flow device, and an example housing;

FIG. 28 is a perspective view of the first flow device, the second flow device, and the housing of FIG. 27; and

FIG. 29 is a rear view of the first flow device, the second flow device, and the housing of FIG. 28.

It will be recognized that the Figures are schematic representations for purposes of illustration. The Figures are provided for the purpose of illustrating one or more implementations with the explicit understanding that the Figures will not be used to limit the scope or the meaning of the claims.

DETAILED DESCRIPTION

Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, and systems for flow distribution in an exhaust aftertreatment system. The various concepts introduced above and discussed in greater detail below may be implemented in any of a number of ways, as the described concepts are not limited to any particular manner of implementation. Examples of specific implementations and applications are provided primarily for illustrative purposes.

I. Overview

Internal combustion engines (e.g., diesel internal combustion engines, etc.) produce exhaust that is often treated by a doser assembly within an exhaust aftertreatment system. The doser assembly typically treats the exhaust using a treatment fluid (e.g., reductant, ammonia, hydrocarbon fluid, etc.) released from the doser assembly by an injector of a doser. The treatment fluid, such as reductant, may be adsorbed by a catalyst member. The adsorbed treatment fluid in the catalyst member may function to reduce NO_Xin the exhaust. The treatment fluid, such as hydrocarbon fluid, may increase a temperature of the exhaust to reduce NO_Xin the exhaust. The doser assembly is mounted on a component of the exhaust aftertreatment system. For example, the doser assembly may be mounted to a decomposition reactor, an exhaust conduit, a panel, or other similar components of the exhaust aftertreatment system.

Mixing the exhaust with the treatment fluid may improve the reduction of NO_Xin the exhaust or improve heating of the exhaust. A device can be used to facilitate mixing between the exhaust and the treatment fluid through turbulent flow (e.g., turbulence, etc.). Turbulence in the form of swirling (e.g., eddies, etc.) improves the mixing characteristics of a fluid. For example, swirling of the exhaust causes dispersal of treatment fluid within the exhaust, thereby improving the mixing between the exhaust and the treatment fluid. However, a device in a flow path of the treatment fluid may be prone to collecting (e.g., accumulating, etc.) deposits generated from treatment fluid. These deposits may reduce a mixing efficiency of the device and a flow rate of the exhaust and/or the treatment fluid within a conduit that the device is within or fluidly coupled to.

Implementations described herein relate to a mixer that includes a plurality of flow devices that cooperate to provide a catalyst member with a substantially uniform flow of a mixture of the exhaust and treatment fluid, facilitate substantially uniform treatment fluid distribution in the exhaust downstream of the mixer, and provide a relatively low pressure drop (e.g., the pressure of the exhaust at the inlet of the mixer less the pressure of the exhaust at the outlet of the mixer, etc.), all in a relatively compact space. The mixer may be configured to dose the exhaust with treatment fluid, cause an internal swirl flow that mixes the treatment fluid within the exhaust, and create a uniform dispersion of the treatment fluid within the uniform flow of the exhaust that flows into the catalyst member. In some implementations, the mixer includes a flow device that includes a plurality of conduits coupled to a plate. The conduits are configured to redirect flow of the exhaust and treatment fluid to increase swirling and enhance mixing between the exhaust and the treatment fluid. The mixer may minimize spray impingement on wall surfaces due to swirl flow and relatively high shear stresses produced by the mixer, thereby mitigating deposit formation and accumulation within the mixer and associated components of the exhaust aftertreatment system.

II. Overview of Exhaust Aftertreatment System

FIG. 1 depicts an exhaust aftertreatment system 100 configured to treat an exhaust released by an internal combustion engine. The exhaust aftertreatment system 100 includes an exhaust conduit system 104 configured to receive the exhaust from the internal combustion engine. The exhaust aftertreatment system 100 further includes a particulate filter 106 (e.g., a diesel particulate filter (DPF), etc.) coupled to the exhaust conduit system 104 and configured to (e.g., structured to, able to, etc.) remove particulate matter, such as soot, from the exhaust flowing in the exhaust conduit system 104. The particulate filter 106 includes an inlet, where the exhaust is received, and an outlet, where the exhaust exits after having particulate matter substantially filtered from the exhaust and/or converting the particulate matter into carbon dioxide. In some implementations, the particulate filter 106 may be omitted.

The exhaust aftertreatment system 100 further includes a decomposition chamber 108 (e.g., reactor, reactor pipe, conduit, etc.) disposed downstream of the particulate filter 106. The decomposition chamber 108 is configured to receive the exhaust from the particulate filter 106. The exhaust aftertreatment system 100 further includes a treatment fluid delivery system 102 coupled to the decomposition chamber 108. The treatment fluid delivery system 102 is configured to deliver treatment fluid to the decomposition chamber 108. The treatment fluid may be, for example, a reductant (e.g., urea, diesel exhaust fluid (DEF), Adblue®, a urea water solution (UWS), an aqueous urea solution (e.g., AUS32, etc.), and/or other similar fluids) or a hydrocarbon fluid (e.g., fuel, oil, additive, etc.). When the reductant is introduced into the exhaust, reduction of emission of undesirable components (e.g., NO_X, etc.) in the exhaust may be facilitated. When the hydrocarbon fluid is introduced into the exhaust, the temperature of the exhaust may be increased (e.g., to facilitate regeneration of components of the exhaust aftertreatment system 100, etc.). For example, the exhaust aftertreatment system 100 may include a spark plug 109 (e.g., igniter, etc.) configured to increase the temperature of the exhaust by combusting the hydrocarbon fluid within the exhaust. The decomposition chamber 108 includes an inlet in fluid communication with the particulate filter 106 to receive the exhaust containing NO_Xemissions and an outlet for the exhaust, NO_Xemissions, ammonia, and/or the treatment fluid to flow to downstream components of the exhaust aftertreatment system 100.

The treatment fluid delivery system 102 includes a doser assembly 112 (e.g., dosing module, etc.) configured to dose the treatment fluid into the decomposition chamber 108 (e.g., via an injector). The doser assembly 112 is mounted to the decomposition chamber 108 such that the doser assembly 112 may dose the treatment fluid into the exhaust flowing through the exhaust conduit system 104.

The doser assembly 112 is fluidly coupled to (e.g., fluidly configured to communicate with, etc.) a treatment fluid source 114. The treatment fluid source 114 may include multiple treatment fluid sources 114. The treatment fluid source 114 may be, for example, a diesel exhaust fluid tank containing Adblue®. A treatment fluid pump 116 (e.g., supply unit, etc.) is used to pressurize the treatment fluid from the treatment fluid source 114 for delivery to the doser assembly 112. In some embodiments, the treatment fluid pump 116 is pressure-controlled (e.g., controlled to obtain a target pressure, etc.). The treatment fluid pump 116 may include a treatment fluid filter 118. The treatment fluid filter 118 filters (e.g., strains, etc.) the treatment fluid prior to the treatment fluid being provided to internal components (e.g., pistons, vanes, etc.) of the treatment fluid pump 116. For example, the treatment fluid filter 118 may inhibit or prevent the transmission of solids (e.g., solidified treatment fluid, contaminants, etc.) to the internal components of the treatment fluid pump 116. In this way, the treatment fluid filter 118 may facilitate prolonged desirable operation of the treatment fluid pump 116. In some embodiments, the treatment fluid pump 116 is coupled (e.g., fastened, attached, affixed, welded, etc.) to a chassis of a vehicle associated with the exhaust aftertreatment system 100.

The doser assembly 112 includes at least one injector 120. Each injector 120 is configured to dose the treatment fluid into the exhaust (e.g., within the decomposition chamber 108, etc.) at an injection axis 119. The exhaust aftertreatment system 100 may include a mixer 121 (e.g., a mixing body assembly, a swirl generating device, a vane plate, inlet plate, deflector plate, etc.). In some embodiments, at least a portion of the mixer 121 may be located within the decomposition chamber 108. In further embodiments, at least a portion of the mixer 121 may also be located in a conduit of the exhaust conduit system 104 (e.g., a conduit upstream of the decomposition chamber 108, etc.). The mixer 121 is configured to receive exhaust from the decomposition chamber 108 and the treatment fluid from the injector 120. The mixer 121 is also configured to facilitate mixing of the exhaust and the treatment fluid. The mixer 121 is configured to facilitate swirling (e.g., tumbling, rotation, etc.) of the exhaust and/or the treatment fluid and mixing (e.g., combination, etc.) of the exhaust and the treatment fluid so as to disperse the treatment fluid within the exhaust downstream of the mixer 121. By dispersing the treatment fluid within the exhaust (e.g., to obtain an increased uniformity index, etc.) using the mixer 121, reduction of emission of undesirable components in the exhaust is enhanced.

In some embodiments, the injection axis 119 extends into the mixer 121. The injection axis 119 may extend into the mixer 121 at an angle relative to a central axis of the mixer 121. For example, in some embodiments, the injection axis 119 may be substantially coincident with a central axis of the mixer 121. In other embodiments, the injection axis 119 may be substantially perpendicular to the central axis of the mixer 121. In yet other embodiment, the injection axis 119 may be substantially parallel to the central axis of the mixer 121.

In some embodiments, the injector 120 is not directly coupled to the mixer 121. In these embodiments, the injector 120 and the mixer 121 may each be coupled to a same component (e.g., housing, panel, chamber, body, etc.). In other embodiments, the injector 120 is directly coupled to the mixer 121. In these embodiments, the injector 120 and the mixer 121 may also each be coupled to the same component. In some embodiments, the injector 120 is not disposed within the mixer 121. In other embodiments, the injector 120 may be at least partially disposed within the mixer 121.

In some embodiments, the treatment fluid delivery system 102 also includes an air pump 122. In these embodiments, the air pump 122 draws air from an air source 124 (e.g., air intake, etc.) and through an air filter 126 disposed upstream of the air pump 122. Additionally, the air pump 122 provides the air to the doser assembly 112 via a conduit. In these embodiments, the doser assembly 112 is configured to mix the air and the treatment fluid into an air-treatment fluid mixture and to provide the air-treatment fluid mixture into the decomposition chamber 108. In other embodiments, the treatment fluid delivery system 102 does not include the air pump 122, the air source 124, and/or the air filter 126. In such embodiments, the doser assembly 112 is not configured to mix the treatment fluid with the air.

The spark plug 109, the doser assembly 112, and the treatment fluid pump 116 are also electrically or communicatively coupled to a treatment fluid delivery system controller 128. The treatment fluid delivery system controller 128 may control the spark plug 109 to ignite the treatment fluid in the decomposition chamber 108. The treatment fluid delivery system controller 128 controls the doser assembly 112 to dose the treatment fluid into the decomposition chamber 108. The treatment fluid delivery system controller 128 may also control the treatment fluid pump 116.

The treatment fluid delivery system controller 128 includes a processing circuit 130. The processing circuit 130 includes a processor 132 and a memory 134. The processor 132 may include a microprocessor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), etc., or combinations thereof. The memory 134 may include, but is not limited to, electronic, optical, magnetic, or any other storage or transmission device capable of providing a processor, ASIC, FPGA, etc. with program instructions. This memory 134 may include a memory chip, Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read Only Memory (EPROM), flash memory, or any other suitable memory from which the treatment fluid delivery system controller 128 can read instructions. The instructions may include code from any suitable programming language. The memory 134 may include various modules that include instructions which are configured to be implemented by the processor 132.

In various embodiments, the treatment fluid delivery system controller 128 is configured to communicate with a central controller 136 (e.g., engine control unit (ECU), engine control module (ECM), etc.) of an internal combustion engine having the exhaust aftertreatment system 100. In some embodiments, the central controller 136 and the treatment fluid delivery system controller 128 are integrated into a single controller.

In some embodiments, the central controller 136 is communicable with a display device (e.g., screen, monitor, touch screen, heads up display (HUD), indicator light, etc.). The display device may be configured to change state in response to receiving information from the central controller 136. For example, the display device may be configured to change between a static state (e.g., displaying a green light, displaying a “SYSTEM OK” message, etc.) and an alarm state (e.g., displaying a blinking red light, displaying a “SERVICE NEEDED” message, etc.) based on a communication from the central controller 136. By changing state, the display device may provide an indication to a user (e.g., operator, etc.) of a status (e.g., operation, in need of service, etc.) of the treatment fluid delivery system 102.

The exhaust aftertreatment system 100 further includes a catalyst member 138 (e.g., SCR (Selective Catalytic Reduction) catalyst member, etc.) disposed downstream of the decomposition chamber 108. As a result, the treatment fluid is injected upstream of the catalyst member 138 such that the catalyst member 138 receives a mixture of the treatment fluid and exhaust. The treatment fluid droplets undergo the processes of evaporation, thermolysis, and hydrolysis to form non-NO_Xemissions (e.g., gaseous ammonia, etc.) within the exhaust conduit system 104.

The catalyst member 138 includes an inlet in fluid communication with the decomposition chamber 108 from which exhaust and treatment fluid are received and an outlet in fluid communication with an outlet 140 of the exhaust conduit system 104. The outlet 140 may release the treated exhaust into an ambient environment or another treatment system.

The exhaust aftertreatment system 100 may further include an oxidation catalyst member (e.g., a diesel oxidation catalyst (DOC), ammonia oxidation catalyst (AMO_X), etc.) in fluid communication with the exhaust conduit system 104 (e.g., downstream of the catalyst member 138, upstream of the particulate filter 106, upstream of the decomposition chamber 108, etc.) to oxidize hydrocarbons and carbon monoxide in the exhaust.

In some implementations, the particulate filter 106 may be positioned downstream of the decomposition chamber 108. For instance, the particulate filter 106 and the catalyst member 138 may be combined into a single unit. In some implementations, the doser assembly 112 may instead be positioned downstream of a turbocharger or upstream of the turbocharger.

The exhaust aftertreatment system 100 may further include a doser mounting bracket 142 (e.g., mounting bracket, coupler, plate, etc.). The doser mounting bracket 142 couples the doser assembly 112 to a component of the exhaust aftertreatment system 100 (e.g., the decomposition chamber 108, etc.). The doser mounting bracket 142 may be configured as an insulator (e.g., vibrational insulator, thermal insulator, etc.). For example, the doser mounting bracket 142 may be configured to mitigate the transfer of heat from the exhaust passing through the exhaust conduit system 104 to the doser assembly 112. In this way, the doser assembly 112 is capable of operating more efficiently and desirably. The doser mounting bracket 142 may be configured to mitigate transfer of vibrations from the component of the exhaust aftertreatment system 100 to the doser assembly 112. Additionally, the doser mounting bracket 142 is configured to aid in reliable installation of the doser assembly 112. This may decrease manufacturing costs associated with the exhaust aftertreatment system 100 and ensure repeated desirable installation of the doser assembly 112.

In various embodiments, the doser mounting bracket 142 couples the doser assembly 112 to the decomposition chamber 108. In some embodiments, the doser mounting bracket 142 couples the doser assembly 112 to an exhaust conduit of the exhaust conduit system 104. For example, the doser mounting bracket 142 may couple the doser assembly 112 to an exhaust conduit of the exhaust conduit system 104 that is upstream of the decomposition chamber 108. In some embodiments, the doser mounting bracket 142 couples the doser assembly 112 to the particulate filter 106 and/or the catalyst member 138. The location of the doser mounting bracket 142 may be varied depending on the application of the exhaust aftertreatment system 100. For example, in some exhaust aftertreatment systems 100, the doser mounting bracket 142 may be located further upstream than in other exhaust aftertreatment systems 100. Furthermore, some exhaust aftertreatment systems 100 may include multiple doser assemblies 112 and therefore may include multiple doser mounting brackets 142.

III. Overview of Example Mixer

FIGS. 2-5 and 27 illustrate various embodiments of a mixer 200 (e.g., the mixer 121, a multi-stage mixer, etc.) configured to facilitate mixing of the exhaust and the treatment fluid. The mixer 200 includes an inlet 202. The inlet 202 is configured to receive exhaust from an exhaust conduit of the exhaust conduit system 104. The mixer 200 further includes an outlet 204. The outlet 204 is configured to provide a mixture of the exhaust and the treatment fluid that is injected by the injector 120 of the doser assembly 112. In some embodiments, the mixer 200 is disposed downstream of the particulate filter 106 and upstream of the catalyst member 138, such that the inlet 202 receives the exhaust from the particulate filter 106 and the outlet 204 provides the mixture of the exhaust and the treatment fluid to the catalyst member 138. In other embodiments, the mixer 200 is disposed upstream of the particulate filter 106 and/or downstream of the catalyst member 138.

As discussed in greater detail below, the mixer 200 includes a plurality of flow devices that segment the mixer 200 into a plurality of stages. Each of the flow devices is structured to alter the flow of the exhaust and/or the treatment fluid so that the flow devices cumulatively cause the exhaust to obtain a target flow distribution and/or the treatment fluid to obtain a target uniformity index (e.g., uniformity distribution, etc.) at the outlet 204. Obtaining certain flow distributions and treatment fluid uniformities indices may be important in the operation of the exhaust aftertreatment system 100. For example, it may be desirable to obtain a uniform flow distribution and treatment fluid uniformity index at an inlet of the catalyst member 138 (i.e., when the catalyst member 138 is downstream of the mixer 200) because such a flow distribution allows the catalyst member 138 to obtain a relatively high NO_Xconversion efficiency.

The mixer 200 includes a first flow device 210 disposed downstream of the inlet 202 and upstream of the outlet 204 and configured to receive the exhaust from the inlet 202. The first flow device 210 may be disposed upstream of the injector 120. As the exhaust enters the mixer 200 through the inlet 202, prior to the exhaust encountering the first flow device 210, the exhaust is in stage zero (e.g., “Stage 0”) of the stages (i.e., stage zero extends between the inlet 202 and the first flow device 210). In stage zero, the exhaust has yet to be impacted by any of the flow devices (e.g., the first flow device 210, etc.).

As illustrated in FIGS. 6-8, the first flow device 210 includes a plurality of main vanes 212 and a plurality of main vane apertures 214 interspaced between the main vanes 212. Each of the main vane apertures 214 is configured to receive the exhaust and to cooperate with at least one of the main vanes 212 to facilitate swirling of the exhaust. The main vanes 212 and the main vane apertures 214 provide a swirl flow, thereby creating low pressure regions and increasing swirling (e.g., turbulence, etc.) of the exhaust flow. The main vane apertures 214 provide several openings between adjacent main vanes 212, such that each of the main vanes 212 independently swirls the exhaust and such that the main vanes 212 collectively form the swirl flow in the exhaust.

In some embodiments, the main vanes 212 are static (e.g., fixed, etc.), thereby reducing complexity in manufacturing and cost. In other embodiments, the main vanes 212 are dynamic and structured to selectively move via servos, motors, etc. operated using a controller, thereby providing control over the exhaust flowrate passing through the first flow device 210 and intensity of exhaust swirling.

The main vanes 212 are positioned (e.g., curved, angled, bent, etc.) to cause a swirl (e.g., turbulent, etc.) flow of the exhaust to encourage mixing between the exhaust and the treatment fluid downstream of the first flow device 210. In some embodiments, the main vanes 212 are substantially straight (e.g., substantially disposed along a plane, having a substantially constant slope along the main vane 212, etc.). In other embodiments, the main vanes 212 are curved (e.g., not substantially disposed along a plane, having different slopes along the main vane 212, having edges which are curved relative to the remainder of the main vane 212, etc.). In some embodiments, adjacent main vanes 212 are positioned so as to extend over one another. In these embodiments, the main vanes 212 may be straight and/or curved. In other embodiments, adjacent main vanes 212 are positioned so as to not extend over one another. In some embodiments, each main vane 212 may be independently configured so that the main vanes 212 are individually tailored to achieve a target configuration of the first flow device 210 such that the mixer 200 is tailored for a target application.

Each of the main vanes 212 may be defined by a vane angle (e.g., relative to a center axis of the mixer 200, etc.) that is related to the swirl produced by that main vane 212. The vane angle for each of the main vanes 212 may be different from the vane angle for any of the others of the main vanes 212. The first flow device 210 may include any number of the main vanes 212. In some embodiments, the first flow device 210 includes between four and twelve of the main vanes 212.

The mixer 200 includes a second flow device 220. The second flow device 220 is disposed downstream of the first flow device 210 and upstream of the outlet 204 and configured to receive the exhaust from the first flow device 210. The second flow device 220 may be disposed downstream of the injector 120. As the exhaust exits the first flow device 210, prior to the exhaust encountering other flow devices (e.g., the second flow device 220) and/or exiting the mixer 200 via the outlet 204, the exhaust is in stage one (e.g., “Stage I”) of the stages (i.e., stage one extends between the first flow device 210 and the second flow device 220). In stage one, the exhaust has been impacted by first flow device 210 and not yet impacted by the second flow device 220, and the treatment fluid has not yet been impacted by the second flow device 220.

The second flow device 220 includes a plate 222. In some embodiments, the plate 222 is flat (e.g., planar). In other embodiments, the plate 222 is curved (e.g., non-planar). The second flow device 220 includes a plurality of conduits 224 coupled to the plate 222. The second flow device 220 may include any number of the conduits 224, such as two of the conduits 224, three of the conduits 224 (FIGS. 12-14, 27, and 29), four of the conduits 224 (FIGS. 9-11), five of the conduits 224, and the like. In some embodiments, the second flow device 220 includes one of the conduits 224. The conduits 224 may be manufactured with high tolerances (e.g., +/−5%, +/−1%, etc. from a given value), thereby simplifying and decreasing a cost of a manufacturing process of the conduits 224. The tolerances may be relative to a one-dimensional value, such as a width, a length, or a height, a two-dimensional value, such as a surface area or an open area (e.g., a flow area, etc.), or a three-dimensional value, such as a volume. The tolerances relative to the one-dimensional value, the two-dimensional value, and the three-dimensional value may be different from one another. For example, the tolerances for the one-dimensional value may be less than the tolerances for the two-dimensional value (e.g., the tolerance for the one-dimensional value may be +/−2.5% from the one-dimensional value while the tolerance for the two-dimensional value may be +/−5% from the two-dimensional value, etc.).

Each of the conduits 224 includes a first sidewall 230 extending outward of the plate 222. In some embodiments, the first sidewall 230 is orthogonal to the plate 222. In other embodiments, the first sidewall 230 defines an acute angle (i.e., an angle greater than 0 degree and less than 90 degrees) or an obtuse angle (i.e., an angle greater than 90 degrees and less than 180 degrees) relative to the plate 222, where the angle extends from the plate 222 to a reference plane that the first sidewall 230 extends along. In some embodiments, the first sidewall 230 is flat. In other embodiments, the first sidewall 230 is curved.

Each of the conduits 224 further includes a second sidewall 232. The second sidewall 232 extends outward of the plate 222 and opposes the first sidewall 230. The first sidewall 230 may be disposed closer to a center of the plate 222 than the second sidewall 232. In some embodiments, the second sidewall 232 is orthogonal to the plate 222. In other embodiments, the second sidewall 232 defines an acute angle or an obtuse angle relative to the plate 222, where the angle extends from the plate 222 to a reference plane that the second sidewall 232 extends along. In some embodiments, the second sidewall 232 is flat. In other embodiments, the second sidewall 232 is curved.

As illustrated in FIG. 11, the plate 222 has a plate radius R1. The second flow device 220 includes a first conduit radius R2 defined between the center of the plate 222 and the first sidewall 230 of one of the conduits 224. The second flow device 220 further includes a second conduit radius R3 defined between the center of the plate 222 and the second sidewall 232 of one of the conduits 224. In some embodiments, a first ratio of the first conduit radius R2 to the plate radius R1 is between 0.1 and 0.4, inclusive, and preferably between 0.2 and 0.3, inclusive. In some embodiments, a second ratio of the second conduit radius R3 to the plate radius R1 is greater than 0.7 and less than 1, and preferably between 0.8 and 0.9, inclusive.

Each of the conduits 224 further includes a main wall 234 extending from the plate 222 and between the first sidewall 230 and the second sidewall 232. In some embodiments, as shown in FIGS. 9-26, the main wall 234 includes a first portion 236 extending from the plate 222 and a second portion 238 extending from the first portion 236. In some embodiments, as illustrated in FIGS. 9-19 and 22-26, the first portion 236 is curved (i.e., the first portion 236 is a curved portion) and the second portion 238 is flat (i.e., the second portion 238 is a flat portion). In some further embodiments, as illustrated in FIGS. 16, 18, and 22, the second portion 238 that is flat (e.g., the flat portion) is parallel to the plate 222. In other further embodiments, as illustrated in FIGS. 20 and 23-26, the second portion 238 that is flat (e.g., the flat portion) is non-parallel to the plate 222. In some embodiments, as illustrated in FIG. 18, a section of the second portion 238 (e.g., the flat portion, etc.) overlaps (e.g., covers, encapsulates, etc.) a section of the plate 222, such that a reference axis orthogonal to the plate 222 extends through both the section of the second portion 238 and the section of the plate 222. For example, in a plan view or in a cross-sectional view (FIG. 18), the section of the second portion 238 covers the section of the plate 222. In other embodiments, as illustrated in FIG. 16, the second portion 238 does not overlap of the plate 222, such that the reference axis orthogonal to the plate 222 extends through the plate 222 but does not extend through the second portion 238. For example, in a plan view or in a cross-sectional view (FIG. 16), the second portion 238 does not cover any sections of the plate 222.

In some embodiments, as illustrated in FIGS. 20-21, the first portion 236 is orthogonal to the plate 222. In some further embodiments, as illustrated in FIG. 21, the second portion 238 is orthogonal to the first portion 236 and parallel to the plate 222. In other further embodiments, the second portion 238 extends from the first portion 236 at a non-zero angle relative to the plate 222. For example, as illustrated in FIG. 20, the non-zero angle is greater than zero. In some examples, the non-zero angle is less than zero.

Each of the conduits 224 includes a conduit inlet 240 that is coplanar with the plate 222 and configured to receive the exhaust from the inlet 202 and/or the first flow device 210, and a conduit outlet 242 that forms an angle with the plate 222. The conduit outlet 242 is configured to release the exhaust received from the conduit inlet 240. The angle between the conduit outlet 242 and the plate 222 may be between 35 degrees and 145 degrees, inclusive.

In some embodiments, as illustrated in FIGS. 15, 17, 20, and 21, the angle between the conduit outlet 242 and the plate 222 is equal to, or approximately equal to, 90 degrees, such that the fluid (e.g., the exhaust, the treatment fluid, mixture of the exhaust and the treatment fluid, etc.) flow exits the conduit outlet 242 in a direction parallel, or approximately parallel, to the plate 222. These embodiments may guide the flow with minimal slip or bypass and encourage the fluid flow to contact the plate 222 and/or the conduits 224 and remove or reduce deposits around the plate 222 and/or the conduits 224 by removing liquid film accumulations of the treatment fluid on the plate 222 and/or the conduits 224 that can result in deposit formations.

In other embodiments, as illustrated in FIG. 19, the angle between the conduit outlet 242 and the plate 222 is greater than 90 degrees and less than 145 degrees, such that the fluid flow exits the conduit outlet 242 in a direction non-parallel to the plate 222 and extending away from the plate 222. These embodiments may guide the flow with minimal slip or bypass and encourage the fluid flow to flow downstream of the second flow device 220, thereby reducing backpressure in the mixer 200.

In yet other embodiments, the angle between the conduit outlet 242 and the plate 222 is less than 90 degrees and greater than 0 degrees, such that the fluid flow exits the conduit outlet 242 in a direction non-parallel to the plate 222 and extending towards the plate 222. These embodiments may guide the flow with minimal slip or bypass and encourage the fluid flow to contact the plate 222 and/or the conduits 224 and remove or reduce deposits around the plate 222 and/or the conduits 224. The angle between the conduit outlet 242 and the plate 222 may be determined based on requirements of the mixer 200 and/or of the exhaust aftertreatment system 100. For example, the angle between the conduit outlet 242 and the plate 222 may be determined based on target swirl level, target pressure drop, target ammonia uniformity, and/or target deposit performance.

In some embodiments, as illustrated in FIGS. 22, the first sidewall 230 and the second sidewall 232 have equal or substantially equal heights, such that the fluid flow exiting the conduit outlet 242 is uniform in a radial direction along the plate 222.

In other embodiments, as illustrated in FIGS. 23 and 25, a height of the first sidewall 230 is greater than a height of the second sidewall 232, such that the fluid flow exiting the conduit outlet 242 is biased towards a center of the plate 222 in the radial direction. These embodiments may eliminate or minimize treatment fluid deficiencies that may exist towards the center of the plate 222 or a center of the mixer 200, thereby improving treatment fluid uniformity and, ultimately, NO_Xconversion efficiency.

In yet other embodiments, as illustrated in FIGS. 24 and 26, the height of the first sidewall 230 is less than the height of the second sidewall 232, such that the fluid flow exiting the conduit outlet 242 is biased towards an outer edge (e.g., periphery, etc.) of the plate 222 in the radial direction. These embodiments may eliminate or minimize treatment fluid deficiencies that may exist towards the outer edge of the plate 222 or an outer edge of the mixer 200, thereby improving treatment fluid uniformity and, ultimately, NO_Xconversion efficiency.

The conduit inlet 240 defines a conduit inlet open area and the conduit outlet 242 defines a conduit outlet open area. In some embodiments, a ratio of the conduit outlet open area to the conduit inlet open area is between 0.5 and 2, inclusive. For example, the ratio of the conduit outlet open area to the conduit inlet open area may be equal to, or approximately equal to, 1, such that the conduit outlet open area is equal to, or approximately equal to, the conduit inlet open area. In other embodiments, the ratio of the conduit outlet open area to the conduit inlet open area is less than 0.5 or greater than 2.

As illustrated in FIGS. 15 and 17, the conduit outlet 242 of at least one of the conduits 224 has a length L1 extending from the first sidewall 230 to the second sidewall 232 and a height H1 extending from the main wall 234 to the plate 222. In some embodiments, a ratio of the length L1 to the height H1 is between 1.5 and 5, inclusive. In other embodiments, the ratio of the length L1 to the height H1 is less than 1.5 or greater than 5. The ratio of the length L1 to the height H1 may be determined based on various requirements of the mixer 200 and/or the exhaust aftertreatment system 100. For example, the ratio of the length L1 to the height H1 may be determined based on target flow split between the conduits 224, target pressure drop, target treatment fluid uniformity, target deposit performance, and/or available space volume. The ratio of the length L1 to the height H1 may balance fluid flow between the conduits 224 and/or direct fluid flow from a particular conduit of the conduits 224 toward a target downstream area.

In some embodiments, as illustrated in FIGS. 12-14, the plate 222 includes at least one aperture (e.g., an axial opening, etc.) 244 disposed away from the conduits 224. The plate 222 may include any number of the aperture 244, such as one aperture 244, two apertures 244, five apertures 244, and the like. In embodiments in which the plate 22 includes more than one aperture 244, each aperture 244 can include equal or unequal dimensions or open areas relative to other apertures 244. The aperture 244 may be disposed between two adjacent conduits of the conduits 224. In some embodiments, as illustrated in FIGS. 12-14, 28, and 29, the apertures 244 have an elliptical shape. In other embodiments, at least one of the apertures 244 has a non-elliptical shape, such as a squarer shape, a rectangular shape, a triangular shape, a trapezoidal shape, a circular shape, a semi-circular shape, or the like. For example, as illustrated in FIG. 14, the apertures 244 include two apertures 244 that have an elliptical shape and one aperture 244 that has a rectangular shape.

The aperture 244 defines a first open area on the plate 222. The conduit outlet 242 defines a second open area (e.g., conduit outlet open area). In some embodiments, the second open area is equal to 35% to 150%, inclusive, of the first open area. In other embodiments, the second open area is less than 35% or greater than 150% of the first open area.

The conduits 224 may be contained within a sector of the plate 222. In some embodiments, as illustrated in FIGS. 11 and 12, an angle span A1 of the sector that the conduits 224 are contained within is between 160 degrees and 225 degrees, inclusive. In other embodiments, the angle span A1 of the sector that the conduits 224 are contained within is greater than 0 degrees and less than 160 degrees or greater than 225 degrees and less than 365 degrees.

In some embodiments, the aperture 244 is disposed between two adjacent conduits of the conduits 224 within the sector of the plate 222 where the conduits 224 are contained. In some embodiments, the aperture 244 includes at least two apertures 244, where a first aperture of the two apertures 244 is disposed within the sector of the plate 222 where the conduits 224 are contained and a second aperture of the two apertures 244 is disposed outside of the sector of the plate 222 where the conduits 224 are contained.

As illustrated in FIGS. 2-5, 9, and 10, the mixer 200 includes a third flow device 250 disposed downstream of the second flow device 220 and upstream of the outlet 204 and configured to receive the exhaust and the treatment fluid from the second flow device 220. As the exhaust exits the second flow device 220, prior to the exhaust encountering other flow devices and/or exiting the mixer 200 via the outlet 204, the exhaust is in stage two (e.g., “Stage II”) of the stages (i.e., stage two extends between the second flow device 220 and the third flow device 250). In stage two, the exhaust and the treatment fluid have been impacted by second flow device 220 and not yet impacted by the third flow device 250.

The third flow device 250 includes a plurality of peripheral apertures 252 located along a periphery of the third flow device 250. The third flow device 250 defines a peripheral aperture distance between a center of the third flow device 250 and a center of each of the peripheral apertures. In some embodiments, the peripheral aperture distance is 90% to 98%, inclusive, of a radius of the third flow device 250. In other embodiments, the peripheral aperture distance is less than 90% or greater than 98% of the radius of the third flow device 250. In some embodiments, as illustrated in FIGS. 5, 9, and 10, the peripheral apertures 252 have a circular shape. In other embodiments, at least one of the peripheral apertures 252 has a non-circular shape, such as a square shape, a rectangular shape, a triangular shape, a trapezoidal shape, a semi-circular shape, an elliptical shape, or the like.

The third flow device 250 includes a main aperture 254. The main aperture 254 includes a main aperture open area greater than a peripheral aperture open area of one peripheral aperture of the peripheral apertures 252. A ratio of a hydraulic radius, which is defined as a ratio of a cross-sectional area of fluid flow to a length of a wetted perimeter, of the main aperture 254 to a hydraulic radius of the third flow device 250 is between from 0.4 and 0.7, inclusive. In some embodiments, as illustrated in FIGS. 5, 9, and 10, the main aperture 254 is located off-center of the third flow device 250. In other embodiments, the main aperture 254 is centered on the third flow device 250. For example, the main aperture 254 and the third flow device 250 may be coaxial. An eccentricity of the main aperture 254, which is defined as a ratio of a distance between a center of the main aperture 254 and a center of the third flow deice 250 to the hydraulic radius of the third flow device 250, can range between 0 and 0.5, inclusive. In some embodiments, as illustrated in FIGS. 9 and 10, the main aperture 254 has a circular shape. In other embodiments, the main aperture 254 has a non-circular shape, such as a square shape, a rectangular shape, a triangular shape, a trapezoidal shape, a semi-circular shape, an elliptical shape, or the like.

In some embodiments, as illustrated in FIGS. 9 and 10, in a plan view, the main aperture 254 overlaps at least a portion of at least one conduit of the conduits 224 of the second flow device 220. In some embodiments, in a plan view, the main aperture 254 overlaps at least a portion of the aperture 244 of the second flow device 220. In other embodiments, in a plan view, the main aperture 254 overlaps both the at least a portion of the at least one conduit of the conduits 224 of the second flow device 220 and the at least the portion of the aperture 244 of the second flow device 220. In yet other embodiments, in a plan view, the main aperture 254 overlaps a region of the second flow device 220 that does not include the conduits 224 or the aperture 244.

In some embodiments, as illustrated in FIG. 10, the third flow device 250 includes a plurality of auxiliary apertures 256 located between the peripheral apertures 252 and the main aperture 254. In some embodiments, the auxiliary apertures 256 overlap a region of the second flow device 220 that does not include the conduits 224. In some examples, the auxiliary apertures 256 overlap a region of the second flow device 220 that does not include the conduits 224 but includes at least a portion of the aperture 244. In other examples, the auxiliary apertures 256 overlap a region of the second flow device 220 that does not include the conduits 224 and the aperture 244. In other embodiments, the auxiliary apertures 256 overlap at least a portion of at least one conduit of the conduits 224. In some examples, the auxiliary apertures 256 overlap the at least the portion of the at least one conduit of the conduits 224 but do not overlap the aperture 244. In other examples, the auxiliary apertures 256 overlap the at least the portion of the at least one conduit of the conduits 224 and at least a portion of the aperture 244. In yet other embodiments, the auxiliary apertures 256 overlap at least a portion of the aperture 244.

In some embodiments, as illustrated in FIG. 10, the auxiliary apertures 256 have a circular shape. In other embodiments, at least one of the auxiliary apertures 256 has a non-circular shape, such as a square shape, a rectangular shape, a triangular shape, a trapezoidal shape, a semi-circular shape, an elliptical shape, or the like.

As the exhaust exits the third flow device 250, prior to the exhaust exiting the mixer 200 via the outlet 204, the exhaust is in stage three (e.g., “Stage III”) of the stages (i.e., stage three extends between the third flow device 250 and the outlet 204). In stage three, the exhaust and the treatment fluid have been impacted by third flow device 250 and not yet released from the mixer 200 via the outlet 204.

In some embodiments, as illustrated in FIGS. 4, 27, and 28, the mixer 200 includes a housing 260 disposed between, and coupled to, the first flow device 210 and the second flow device 220. In some embodiments, as illustrated in FIGS. 5 and 27, the main vanes 212 of the first flow device 210 extend at least partially within the housing 260. In some embodiments, the housing 260 may be directly coupled to the decomposition chamber 108.

The housing 260 may include an injector aperture 262 that is configured to receive at least a portion of the injector 120 of the doser assembly 112 and/or the treatment fluid from the injector 120. The housing is configured to receive the treatment fluid from the injector 120 via the injector aperture 262 and the exhaust from the first flow device 210, and facilitate mixing between the exhaust and the treatment fluid at the stage one using turbulent flow of the exhaust caused by the first flow device 210.

The housing 260 may include a cross-sectional area that is less than a cross-sectional of the decomposition chamber 108, such that, assuming that a volumetric flow rate of the exhaust is constant, a velocity of the exhaust increases when entering the housing 260 such that turbulent flow of the exhaust increases within the housing 260, thereby further encouraging mixing in the housing 260.

In some embodiments, as illustrated in FIG. 28, the housing 260 includes a flange 264 proximate the first flow device 210. The flange 264 may extend in a radial direction away from the first flow device 210. The housing 260 may include a plurality of slots 266 extending through the flange 264. Each of the slots 266 is configured to facilitate flow of the exhaust through the flange 264, allowing portions of the exhaust to bypass the first flow device 210 and continue flowing through the mixer 200 and/or the decomposition chamber 108. This results in reducing a pressure drop (e.g., a decrease in pressure, etc.) within the decomposition chamber 108, assisting the mixer 200 in efficiently dispersing the treatment fluid within the exhaust downstream of the mixer 200. The slots 266 may be disposed evenly circumferentially around the flange 264.

It is to be appreciated that the mixer 200 may include any combination of the first flow device 210, the second flow device 220, and the third flow device 250, including combinations with multiple first flow devices 210, multiple second flow devices 220, and/or multiple third flow devices 250 and combinations without the first flow device 210, the second flow device 220, and/or the third flow device 250.

For example, in some embodiments, as illustrated in FIG. 27, the mixer 200 excludes the third flow device 250. In these embodiments, the mixture of the exhaust and the treatment fluid exiting the second flow device 220 is communicated directly to the outlet 204 of the mixer 200. Further in these embodiments, in place of stage three, as the exhaust exits the second flow device 220, prior to the exhaust exiting the mixer 200 via the outlet 204, the exhaust is in stage four (e.g., “Stage IV”) of the stages (i.e., stage four extends between the second flow device 220 and the outlet 204). In stage four, the exhaust and the treatment fluid have been impacted by second flow device 220 and not yet released from the mixer 200 via the outlet 204.

IV. Configuration of Example Embodiments

While this specification contains many specific implementation details, these should not be construed as limitations on the scope of what may be claimed but rather as descriptions of features specific to particular implementations. Certain features described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Moreover, although features may be described as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can, in some cases, be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

As utilized herein, the terms “substantially,” “generally,” “approximately,” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the appended claims.

The term “coupled” and the like, as used herein, mean the joining of two components directly or indirectly to one another. Such joining may be stationary (e.g., permanent) or moveable (e.g., removable or releasable). Such joining may be achieved with the two components or the two components and any additional intermediate components being integrally formed as a single unitary body with one another, with the two components, or with the two components and any additional intermediate components being attached to one another.

The terms “fluidly coupled to” and the like, as used herein, mean the two components or objects have a pathway formed between the two components or objects in which a fluid, such as air, treatment fluid, an air-treatment fluid mixture, exhaust, hydrocarbon fluid, an air-hydrocarbon fluid mixture, may flow, either with or without intervening components or objects. Examples of fluid couplings or configurations for enabling fluid communication may include piping, channels, or any other suitable components for enabling the flow of a fluid from one component or object to another.

It is important to note that the construction and arrangement of the various systems shown in the various example implementations is illustrative only and not restrictive in character. All changes and modifications that come within the spirit and/or scope of the described implementations are desired to be protected. It should be understood that some features may not be necessary, and implementations lacking the various features may be contemplated as within the scope of the disclosure, the scope being defined by the claims that follow. When the language “a portion” is used, the item can include a portion and/or the entire item unless specifically stated to the contrary.

Also, the term “or” is used, in the context of a list of elements, in its inclusive sense (and not in its exclusive sense) so that when used to connect a list of elements, the term “or” means one, some, or all of the elements in the list. Conjunctive language such as the phrase “at least one of X, Y, and Z,” unless specifically stated otherwise, is otherwise understood with the context as used in general to convey that an item, term, etc. may be either X, Y, Z, X and Y, X and Z, Y and Z, or X, Y, and Z (i.e., any combination of X, Y, and Z). Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of X, at least one of Y, and at least one of Z to each be present, unless otherwise indicated.

Additionally, the use of ranges of values (e.g., W1 to W2, etc.) herein are inclusive of their maximum values and minimum values (e.g., W1 to W2 includes W1 and includes W2, etc.), unless otherwise indicated. Furthermore, a range of values (e.g., W1 to W2, etc.) does not necessarily require the inclusion of intermediate values within the range of values (e.g., W1 to W2 can include only W1 and W2, etc.), unless otherwise indicated.

MIXER FOR EXHAUST AFTERTREATMENT SYSTEM

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