EP4792003A1 - Compact exhaust treatment device - Google Patents

Abstract

An exhaust treatment device includes an exhaust treatment and mixing assembly. The exhaust treatment and mixing assembly includes a mixing passage defined by an inner conduit that extends partially along the length of the outer housing. The mixing passage provides fluid communication between a first region and a second region of an interior space. The exhaust treatment and mixing assembly includes a mixing structure positioned outside of a first region end of the inner conduit for swirling the exhaust flow directed from an inlet into the inner conduit. The exhaust treatment and mixing assembly includes a flow member positioned within the inner conduit. The exhaust treatment and mixing assembly includes an exhaust expansion feature that extends from a second region end of the inner conduit with a free end that terminates toward an exhaust treatment substrate and an outer housing side wall.

Description

COMPACT EXHAUST TREATMENT DEVICE

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Application Serial No. 63/589,088, filed October 10, 2023, the disclosure of which is hereby incorporated by reference in its entirety.

BACKGROUND

[0002] Vehicles equipped with diesel engines typically include exhaust systems that have aftertreatment components such as selective catalytic reduction catalyst devices, lean NOx catalyst devices, or lean NOxtrap devices to reduce the amount of undesirable gases, such as nitrogen oxides (NOx) in the exhaust. For these types of aftertreatment devices to work properly, a doser injects reactants, such as urea, ammonia, or hydrocarbons, into the exhaust gas. As the exhaust gas and reactants flow through the aftertreatment device, the exhaust gas and reactants convert the undesirable gases, such as NOx, into more acceptable gases, such as nitrogen and oxygen. However, the efficiency of the aftertreatment system depends upon how evenly the reactants are mixed with the exhaust gases. There is a need for improved efficiency within compact exhaust treatment devices.

SUMMARY

[0003] In general terms, this disclosure is directed to a compact exhaust treatment device. In some embodiments, and by non-limiting example, the exhaust treatment device includes an outer housing that extends along a length between first and second end walls. The outer housing may also include a side wall that extends along the length from the first end wall to the second end wall. The outer housing defines an interior space. The exhaust treatment device includes a divider wall within the interior space of the outer housing. The divider wall is positioned at an intermediate location along the length of the outer housing. The divider wall separates the interior space of the outer housing into a first region and a second region. The first region is defined between the divider wall and the first end wall, and the second region is defined between the divider wall and the second end wall. The exhaust treatment device includes an inlet that is in fluid communication with the first region of the interior space and an outlet that is in fluid communication with the second region of the interior space. The exhaust treatment device includes an exhaust treatment substrate mounted in the second region of the interior space and an exhaust treatment and mixing assembly. The mixing assembly includes a mixing chamber disposed in the first region of the outer housing. The exhaust treatment and mixing assembly also includes an inner conduit disposed within the outer housing. The inner conduit defines a mixing passage that extends partially along the length of the outer housing. The mixing passage provides fluid communication between the mixing chamber and the second region of the interior space. The exhaust treatment and mixing assembly also includes an exhaust passage that surrounds the inner conduit. The exhaust passage is configured to direct exhaust flow from the inlet into the mixing chamber. The exhaust treatment and mixing assembly also includes a mixing structure for swirling the exhaust flow directed from the exhaust passage into the mixing chamber. The exhaust treatment and mixing assembly also includes a flow member disposed at the inner conduit. The flow member restricts a cross-sectional area of the mixing passage. The exhaust treatment and mixing assembly also includes a dispenser mounting location provided at the first end wall of the outer housing for mounting a dispenser used for dispensing a reactant into the mixing chamber. In certain examples, the flow member is disposed at a second end of the inner conduit. In certain examples, the flow member is a cross-bar arrangement with a plurality of members that extend across the cross-sectional area of the mixing passage. In certain examples, each of the members extends outwardly from a central region and normal to a central longitudinal axis of the exhaust treatment device. In certain examples, the cross-bar arrangement includes four members. In certain examples, the flow member further includes a ring which surrounds ends of the four members and the ring contacts an inner diameter of the inner conduit. In certain examples, the cross-bar arrangement and ring are integral to each other. In certain examples, the flow member is configured to temporarily divide the exhaust flow into separate portions. In certain examples, the flow member has a thickness that is less than its width. In certain examples, the mixing passage includes an exhaust expansion feature that extends from a first end at the inner conduit and continuing to a second end that is axially spaced from the exhaust treatment substrate. In certain examples, the exhaust expansion feature has a frustoconical tube shape. In certain examples, the exhaust expansion feature is spaced radially inwardly from the side wall. In certain examples, the exhaust expansion feature extends between 25 and 30 percent of the distance between a second end of the inner conduit and an upstream face of the exhaust treatment substrate. In certain examples, the exhaust expansion feature extends outwardly from a second end of the inner conduit at an angle of 45 degrees relative to a central longitudinal axis. In certain examples, the exhaust treatment device includes a reactant dispenser disposed at the dispenser mounting location. In certain examples, the exhaust treatment substrate is a selective catalytic reduction catalyst. In certain examples, the flow member is centered about a central longitudinal axis. In certain examples, the flow member includes four flow apertures configured to enable exhaust to flow therethrough.

[0004] In some embodiments, and by non-limiting example, the exhaust treatment device includes an outer housing that extends along a length between first and second end walls. The outer housing also includes a side wall that extends along the length from the first end wall to the second end wall. The outer housing defines an interior space. The exhaust treatment device includes a divider wall within the interior space of the outer housing. The divider wall is positioned at an intermediate location along the length of the outer housing. The divider wall separates the interior space of the outer housing into a first region and a second region. The first region is defined between the divider wall and the first end wall, and the second region is defined between the divider wall and the second end wall. The exhaust treatment device includes an inlet that is in fluid communication with the first region of the interior space and an outlet that is in fluid communication with the second region of the interior space. The exhaust treatment device includes an exhaust treatment substrate mounted in the second region of the interior space and an exhaust treatment and mixing assembly. The mixing assembly includes a mixing chamber disposed in the first region of the outer housing. The exhaust treatment and mixing assembly also includes an inner conduit disposed within the outer housing. The inner conduit defines a mixing passage that extends partially along the length of the outer housing. The mixing passage provides fluid communication between the mixing chamber and the second region of the interior space. The exhaust treatment and mixing assembly also includes an exhaust passage that surrounds the inner conduit. The exhaust passage is configured to direct exhaust flow from the inlet into the mixing chamber. The exhaust treatment and mixing assembly also includes a mixing structure for swirling the exhaust flow directed from the exhaust passage into the mixing chamber. The exhaust treatment and mixing assembly also includes an exhaust expansion feature that extends from a second region end of the inner conduit with a free end axially spaced from the exhaust treatment substrate and radially spaced from the side wall of the outer housing. The exhaust treatment and mixing assembly also includes a dispenser mounting location at the first end wall of the outer housing for mounting a dispenser used for dispensing a reactant into the mixing chamber. In certain examples, the exhaust expansion feature is a frustoconical tube. In certain examples, the exhaust expansion feature is fixed to a second end of the inner conduit. In certain examples, the exhaust expansion feature is integral to the inner conduit. In certain examples, the exhaust expansion feature extends outwardly from a second end of the inner conduit and towards the exhaust treatment substrate at an angle of 45 degrees about a longitudinal central axis. In certain examples, the exhaust treatment device includes a flow member disposed at the inner conduit, where the flow member is configured to restrict a cross-sectional area of the mixing passage. In certain examples, the flow member is disposed at a second end of the inner conduit. In certain examples, the flow member is a cross-bar arrangement with a plurality of members that extend across the cross-sectional area of the mixing passage. In certain examples, each of the members extends outwardly from a central region and normal to a central longitudinal axis of the exhaust treatment device. In certain examples, the cross-bar arrangement includes four members. In certain examples, the flow member includes a ring which surrounds ends of the four members and wherein the ring contacts an inner diameter of the inner conduit. In certain examples, the cross-bar arrangement and ring are integral to each other. In certain examples, the flow member is configured to temporarily divide the exhaust flow into separate portions. In certain examples, the flow member has a thickness that is less than its width.

[0005] In some embodiments, and by non-limiting example, the exhaust treatment device includes an outer housing with opposite first and second end walls and a length that extends between the first and second end walls. The outer housing also includes a side wall that extends along the length from the first end wall to the second end wall. The outer housing defines an interior space. The exhaust treatment device includes a divider wall within the interior space of the outer housing. The divider wall is positioned at an intermediate location along the length of the outer housing. The divider wall separates the interior space of the outer housing into a first region and a second region. The first region i defined between the divider wall and the first end wall and the second region is defined between the divider wall and the second end wall. The exhaust treatment device includes an inlet that is in fluid communication with the first region of the interior space and an outlet that is in fluid communication with the second region of the interior space. The exhaust treatment device includes an exhaust treatment and mixing assembly. The exhaust treatment and mixing assembly includes a mixing passage defined by an inner conduit that extends partially along the length of the outer housing. The mixing passage provides fluid communication between the first region and the second region of the interior space. The exhaust treatment and mixing assembly includes a mixing structure positioned outside of a first region end of the inner conduit for swirling the exhaust flow directed from the inlet into the inner conduit. The exhaust treatment and mixing assembly includes a flow member positioned within the inner conduit. The exhaust treatment and mixing assembly includes an exhaust expansion feature that extends from a second region end of the inner conduit with a free end that terminates toward the exhaust treatment substrate and the outer housing side wall.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] FIG. l is a schematic depiction of an engine exhaust system in accordance with the principles of the present disclosure.

[0007] FIG. 2 is a perspective view of an exhaust treatment device in accordance with the principles of the present disclosure.

[0008] FIG. 3 is a first end view of the exhaust treatment device of FIG. 2.

[0009] FIG. 4 is a side view of the exhaust treatment device of FIG. 2.

[0010] FIG. 5 is a second end view of the exhaust treatment device of FIG. 2.

[0011] FIG. 6 is a cross-sectional view taken along section line 6-6 of FIG. 4.

[0012] FIG. 7 is a cross-sectional view taken along section line 7-7 of FIG. 4.

[0013] FIG. 8 is a cross-sectional view taken along section line 8-8 of FIG. 5.

[0014] FIG. 9 is a perspective view of the cross-sectional view of FIG. 8.

[0015] FIG. 10 is a focused view of a portion of FIG. 8.

[0016] FIG. 11 is a flow diagram of the exhaust treatment device of FIG. 2.

DETAILED DESCRIPTION

[0017] Various embodiments will be described in detail with reference to the drawings, wherein like reference numerals represent like parts and assemblies throughout the several views. Reference to various embodiments does not limit the scope of the claims attached hereto. Additionally, any examples set forth in this specification are not intended to be limiting and merely set forth some of the many possible embodiments for the appended claims.

[0018] Aspects of the present disclosure relate to exhaust treatment devices adapted for use in treating exhaust gas generated by engines such as diesel engines. In certain examples, exhaust treatment devices in accordance with the principles of the present disclosure can be used to treat exhaust generated by diesel engines of vehicles such as over-the-road trucks, off-road vehicles (e.g., agricultural vehicles such as tractors, construction vehicles such as graders, bull-dozers, front end loaders, or other vehicles). Certain aspects of the present disclosure result in an exhaust treatment device that is relatively compact and can be readily mounted under the vehicle hood, under the vehicle cabin, adjacent the vehicle hood, adjacent the vehicle cabin or elsewhere on the vehicle. In certain examples, exhaust treatment devices in accordance with the principles if the present disclosure can be mounted horizontally, vertically or at an angle.

[0019] A selective catalytic reduction (SCR) catalyst device is typically used in an exhaust system to remove undesirable gases such as nitrogen oxides (NOx) from the vehicle's emissions. SCR's are capable of converting NOx to nitrogen and oxygen in an oxygen rich environment with the assistance of reactants such as urea or ammonia, which are injected into the exhaust stream upstream of the SCR through the doser.

[0020] A lean NOx catalyst device is also capable of converting NOx to nitrogen and oxygen. In contrast to SCR's, lean NOx catalysts use hydrocarbons as reducing agents/reactants for conversion of NOx to nitrogen and oxygen. The hydrocarbon is injected into the exhaust stream upstream of the lean NOx catalyst. At the lean NOx catalyst, the NOx reacts with the injected hydrocarbons with the assistance of a catalyst to reduce the NOx to nitrogen and oxygen. While the exhaust treatment system is described as including an SCR, it will be understood that the scope of the present disclosure is not limited to an SCR as there are various catalyst devices, such as those described below, that can be used in accordance with the principles of the present disclosure.

[0021] Lean NOx traps use a material such as barium oxide to absorb NOx during lean burn operating conditions. During fuel rich operations, the NOx is desorbed and converted to nitrogen and oxygen by reaction with hydrocarbons in the presence of catalysts (precious metals) within the traps.

[0022] FIG. 1 is a schematic example of an engine exhaust system 40. The engine exhaust system 40 includes an engine 42, a fuel tank 44 for supplying fuel (e.g., diesel fuel) to the engine 42, an air intake 46, an air fdter 48, and an exhaust conduit 50 for conveying exhaust gas away from the engine 42. The engine exhaust system also includes an exhaust treatment device 100 that is in fluid communication with the exhaust conduit 50, connecting at a device inlet 130. The exhaust treatment device 100 also includes a device outlet 132 which directs treated exhaust to an exhaust conduit 52. The exhaust conduit 52 carries the treated exhaust to an exhaust output 58. An exhaust treatment device such as a diesel particulate fdter (e.g., a flow-through fdter, a wall flow fdter, etc.) or a diesel oxidation catalyst can optionally be provided upstream or downstream from the exhaust treatment device 100. Also, a noise abatement structure such as a muffler can be provided along the exhaust conduit 52.

[0023] The exhaust treatment device 100 is configured to reduce the concentration of NOx (or other contaminants/pollutants) present in the exhaust stream. In one embodiment, the exhaust treatment device 100 includes an exhaust treatment substrate 134, such as an SCR substrate, a lean NOx catalyst, a lean NOx trap or other structure, an SCR coated filter (e.g., a SCR coated DPF or flow-through filter), etc., for removing NOx (or other contaminants such as SO2, CO, VOCs, etc.) from the exhaust stream. The exhaust treatment device 100 also includes a dispenser or doser mounting location 154 at which a doser 156 (e.g., an injector, a spray nozzle, or other dispensing structure) can be mounted to supply a reactant (e.g., urea (e.g., aqueous urea), ammonia, hydrocarbons, or other reducing agents) suitable for reacting with NOx (or other contaminants such as SO2, CO, VOCs, etc.) at the exhaust treatment substrate 134 to reduce the overall concentration of contaminants such as NOx in the exhaust stream. The dispenser mounting location 154 is positioned upstream from the exhaust treatment substrate 134.

[0024] The exhaust treatment device 100 further includes a mixing arrangement 158 that generates turbulence (e.g., swirling) for assisting in mixing and volatilizing the reactant from the doser 156 before the reactant reaches the exhaust treatment substrate 134. In some examples, the mixing arrangement 158 is disposed upstream of the doser mounting location 154. In other examples, however, the mixing arrangement 158 may be disposed downstream of the doser mounting location 154. In certain examples, exhaust treatment substrate 134 can include multiple substrates arranged in series within the device 100 at a location downstream from the doser mounting location 154 and the mixing arrangement 158 (e.g., a DPF, a SCR substrate, and an optional DOC (e.g., a reactant oxidation catalyst for oxidizing excess reactant) arranged in series). In other examples, additional treatment substrates may be downstream from the exhaust treatment device 100. In certain implementations, the exhaust treatment device 100 also includes one or more contaminant sensors 56 (e.g., NOx sensors) and one or more temperature sensors 54. In the depicted embodiment, one set of sensors 54, 56 is positioned at the device inlet 130 and a second set of sensors 54, 56 is positioned at the device outlet 132. Ports 56' are contaminant sensor ports and ports 54' are temperature sensor ports. [0025] While the exhaust treatment substrate 134, positioned downstream from the mixing arrangement 158 and doser mounting location 154, may be referred to as a NOx treatment substrate, it will be appreciated that such substrate can also be referred to generally as an “exhaust treatment substrate” since in other embodiments, in accordance with the principles of the present disclosure, the substrate can be adapted for removing/reducing contaminants other than NOx and the doser 156 can be adapted for delivering reactants suitable for promoting the removal of such alternative contaminants. [0026] It will be appreciated that the various components of the exhaust treatment device 100 are relatively positioned to provide a compact configuration. While the configuration is compact, the components are configured such that the reactants from the doser 156 are effectively mixed and volatized prior to reaching the exhaust treatment substrate 134 such that the exhaust treatment substrate 134 efficiently removes NO_X (or other contaminants such as SO2, CO, VOCs, etc.) from the exhaust stream. In certain embodiments, the exhaust treatment device 100 has a volume less than or equal to 24 liters and is adapted to treat an exhaust flow up to 650 kilograms per hour at rated power. In other embodiments, the exhaust treatment device 100 has a volume less than or equal to 95 liters and is adapted to treat an exhaust flow up to 1700 kilograms per hour at rated power. In other embodiments, the exhaust treatment device 100 has a volume less than or equal to 135 liters and is adapted to treat an exhaust flow up to 2000 kilograms per hour at rated power. In still other embodiments, the ratio of the volume of the exhaust treatment device 100 (liters) to the exhaust flow for which the exhaust treatment device 100 is intended to treat (kilograms per hour at rated power) is in the range of 0.03 to 0.07. In certain embodiments, an upstream face 186 of the exhaust treatment substrate 134 is spaced less than 750 millimeters from the doser 156. In other embodiments, the upstream face 186 of the exhaust treatment substrate 134 is spaced in the range of 230-750 millimeters from the doser 156.

[0027] Referring still to FIG. 1, the exhaust treatment device 100 includes an outer housing 110 including a length L that extends between first and second opposite end walls 112, 114 of the outer housing 110. The outer housing 110 also includes a side wall 116 that extends along the length L from the first end wall 112 to the second end wall 114. In one example, the side wall 116 is cylindrical (e.g., see FIGS. 2-3). In other examples, the side wall 116 can be elliptical, oval, rectangular, or another desired shape. The side wall 116 defines a central longitudinal axis 80 of the outer housing 110. The central longitudinal axis 80 extends along the length L of the outer housing 110. The outer housing 110 defines an interior space 118 of the exhaust treatment device 100. [0028] The exhaust treatment device 100 also includes a divider wall 120 positioned within the interior space 118 of the outer housing 110. The divider wall 120 is positioned at an intermediate location along the length L of the outer housing 110. The divider wall 120 separates the interior space 118 of the outer housing 110 into a first region 122 and a second region 124. The first region 122 is defined between the first end wall 112 and the divider wall 120. The second region 124 is defined between the second end wall 114 and the divider wall 120. The doser mounting location 154 and the mixing arrangement 158 are positioned in the first region 122, and the exhaust treatment substrate 134 is positioned in the second region 124.

[0029] The device inlet 130 is in fluid communication with the first region 122 of the interior space 118 and the device outlet 132 is in fluid communication with the second region 124. In one embodiment, the device inlet 130 is defined through the side wall 116 of the outer housing 110 and is configured for directing exhaust flow into the first region 122. The device inlet 130 can have many different configurations. For example, the device inlet 130 may have a radial configuration, a tangential configuration, or an angled configuration. Additionally, in other examples, the device inlet 130 can be an axial inlet defined through the first end wall 112. The device outlet 132 is shown being defined through the side wall 116 and is configured for receiving exhaust flow from the second region 124 and for directing the exhaust flow out of the outer housing 110. Like the device inlet 130, however, the device outlet 132 can have many configurations. The device outlet 132 may have a radial configuration, a tangential configuration, or an angled configuration. In some embodiments, the device outlet 132 can have an axial configuration in which the device outlet 132 is defined through the second end wall 114. [0030] The mixing arrangement 158 is part of an exhaust treatment and mixing assembly 140 (FIG. 8) positioned within the interior space 118. The exhaust treatment and mixing assembly 140 includes an inner conduit 146 (e.g., a mixing tube) defining a mixing passage 144 that is coaxially aligned with the central longitudinal axis 80 of the outer housing 110. The inner conduit 146 provides fluid communication between the first region 122 and the second region 124 of the interior space 118. As shown in FIG. 1, the inner conduit 146 extends from a mixing chamber 142 of the mixing arrangement 158 to the divider wall 120. The inner conduit 146 provides fluid communication between the mixing chamber 142 and the second region 124 of the interior space 118. The inner conduit 146 has a first end 147 and a second end 148 (see FIG. 8). The inner conduit 146 may be attached to the divider wall 120 at the second end 148 of the inner conduit 146. In one embodiment, the divider wall 120 separates the first region 122 of the interior space 118 from the second region 124 of the interior space 118 such that only the mixing passage 144 provides fluid communication between the first and second regions 122, 124. As will be discussed herein, a flow member 170 may be housed within the inner conduit 146 and in the mixing passage 144.

[0031] The exhaust treatment and mixing assembly 140 further includes an exhaust passage 150 defined between the inner conduit 146 and the side wall 116 of the outer housing 110. In one example, the inner conduit 146 and the side wall 116 are cylindrical and the exhaust passage 150 is annular. In other embodiments, the inner conduit 146 and side wall 116 can be different shapes, such as oval rectangular, elliptical, etc. The exhaust passage 150 is configured to direct exhaust flow from the inlet 130 to the mixing chamber 142. The exhaust passage 150 includes a first end 182 and an opposite second end 184. The first end 182 is positioned adjacent the divider wall 120 and the second end 184 is positioned adjacent the mixing chamber 142. In one example, exhaust flows from device inlet 130 into the exhaust passage 150 between the first end 182 and second end 184 of the exhaust passage 150 and exits at the second end 184 into the mixing chamber 142.

[0032] The mixing arrangement 158 of the exhaust treatment and mixing assembly 140 includes a mixing structure 152 positioned at the second end 184 of the exhaust passage 150. The mixing structure 152 may include a configuration adapted for causing the exhaust flow that exits the second end 184 of the exhaust passage 150 to swirl about the central longitudinal axis 80 of the outer housing 110 or otherwise move in a turbulent fashion. In certain embodiments, the mixing structure 152 can include a plate or frame that defines scoops, baffles, vanes, deflectors, bent tubes, angled tubes, or other direction adjustment structures adapted for causing the exhaust flow to rotate, swirl, or otherwise mix within the mixing chamber 142. In an example, an example mixing structure 152 suitable for use with the mixing arrangement 158 is disclosed in U.S. Patent No. 8,539,761, the disclosure of which is hereby incorporated herein by reference in its entirety.

[0033] The exhaust treatment and mixing assembly 140 may further include the doser mounting location 154 configured to receive a doser 156. FIG. 1 shows the doser mounting location 154 is mounted to the first end wall 112. In one example, the doser mounting location 154 aligns the doser 156 with the central longitudinal axis 80 of the outer housing 110. In use of the doser 156, reactant from a reactant source 62 is dispensed (e.g., sprayed, injected, etc.) into the swirling exhaust within the mixing chamber 142 and towards the mixing passage 144. The swirling exhaust within the mixing chamber 142 provides turbulence for uniformly mixing the reactant in the exhaust. The swirling action is carried from the mixing chamber 142 into the mixing passage 144 of the inner conduit 146. Thus, mixing of the reactant with the exhaust continues as the exhaust flows through the inner conduit 146.

[0034] In certain implementations, the flow member 170 interacts with the swirling action of the exhaust within the inner conduit 146 and creates additional turbulence for mixing. The turbulence continues as the exhaust exits the inner conduit 146 and enters the second region 124 of the interior space 118. An exhaust expansion region 162 is defined between the inner conduit 146 and the exhaust treatment substrate 134. An exhaust expansion feature 160 may extend from the second end 148 of the inner conduit 146 into the exhaust expansion region 162 to improve uniformity of exhaust reaching the exhaust treatment substrate 134. Uniform mixing of the reactant has preferably occurred by the time the exhaust reaches an upstream face 186 of the exhaust treatment substrate 134. By uniformly distributing the reactant within the exhaust stream, the efficiency of the chemical reactions that take place at the exhaust treatment substrate 134 can be enhanced by ensuring that a maximum surface area of the exhaust treatment substrate 134 is used. After the exhaust passes through a downstream face 188 of the exhaust treatment substrate 134, the exhaust exits the outer housing 110 through the device outlet 132. [0035] In some implementations, the flow member 170 is positioned towards the end of the mixing passage 144. In other implementations, however, the flow member 170 may be positioned anywhere along a length of the inner conduit 146. In the example shown on FIGS. 8 and 9, the flow member 170 is positioned at the second end 148 of the inner conduit 146. In other examples, the flow member 170 may be positioned in intermediate positions between first and second ends 147, 148 of the inner conduit 146, or at the first end 147 of the inner conduit 146.

[0036] Referring now to FIG. 6, in certain examples, the flow member 170 includes a plurality of members 172 extending across the passage 144 to define apertures 173 therebetween. In certain implementations, the members 172 are connected together at a ring 171 disposed at an inner periphery of the inner conduit 146. For example, the members 172 may extend across the passage 144 from circumferentially opposite locations on the ring 171. In the example shown, the flow member 170 forms a cross bar arrangement having four members 172a-172d. In other examples, there may be greater or fewer members 172 (e.g., one, two, three, five, six, seven, eight, etc.). In certain examples, each member 172 is the same shape and size as the other members and has a width W. Each member 172 extends outwardly from a central region 174 toward an inner surface 149 of the inner conduit 146. The central region 174 is generally centered about the central longitudinal axis 80 and each member 172a-d extends outwardly from the central region 174 normal to the central longitudinal axis 80. Each member 172a-d extends outwardly from the central region 174 at an angle that is normal to the neighboring members 172. In examples where greater or fewer members 172 are present, the members 172 may extend outwardly from the central region 174 such that the angle between each neighboring member 172 is the same. In some examples, the central region 174 may be positioned radially offset from the central longitudinal axis 80. In some examples, the members 172 may be different shapes or sizes than at least one other member 172. In some examples, the member 172 may extend outwardly from the central region 174 at varying angles (other than 90 degrees) relative to the central longitudinal axis 80. In some embodiments, the members 172 extend to the inner surface 149 of the inner conduit 146. [0037] The flow member 170 may also include a ring 176 that meets the members 172a-d at outward ends 178 and encapsulates them, as seen in FIGS 6 and 9. The ring 176 may have an outer contour that closely matches the inner surface 149 of the inner conduit 146 such that exhaust cannot flow between the ring 176 and the inner surface 149 of the inner conduit 146. In the example shown, the ring 176 has the same width as the members 172a-d. The ring 176 may be integral to the members 172a-d. The flow member 170 may be made from a single piece of material. The flow member 170 may be integral to the divider wall 120. The flow member 170 may be integral to the inner conduit 146. The flow member 170 may be secured, adhered, or otherwise attached to the inner conduit 146.

[0038] The flow member 170 may have varying thickness T (FIG. 10), as measured along the central longitudinal axis 80. In the present example, the ring 176 and members 172 have the same thickness. The ratio between the width W and thickness T may vary. In some examples, the thickness T is less than 10% of the width W. In some examples, the thickness T is less than or equal to 20% of the width. In some examples, the thickness T is less than 30% of the width. In some examples, the thickness T is no more than 2 millimeters.

[0039] Neighboring members 172 (e.g., 172a and 172b, 172b and 172c, 172c and 172d, 172d and 172a) cooperate to define apertures A, B, C, D into which the exhaust traveling through the mixing passage 144 is split. The exhaust is temporarily separated into the different apertures A, B, C, D as the exhaust passes through the flow member 170. By separating the swirling exhaust within the mixing passage 144 with the flow member 170, additional turbulence can be created as eddies of exhaust current form near a downstream side 179 of the flow member 170. In the example shown, the apertures A, B, C, and D have the same areas. In other examples, the apertures A, B, C, D may be different sizes from each other. When the flow member 170 is positioned at the second end 148 of the inner conduit 146 (e.g., as shown in FIG. 9), the turbulent exhaust, created in part by the flow member 170, moves past the flow member 170 into the exhaust expansion region 162 where the turbulent exhaust expands to fill the increased volume as it moves toward the NOx treatment substrate. [0040] The flow member 170 extends across the cross-sectional area defined by the inner surface 149 of the inner conduit 146 (i.e., the available cross-sectional area for exhaust to flow through). Accordingly, the apertures A, B, C, D of the flow member 170 define a reduced cross-sectional area of the flow passage 144 through which the exhaust may pass to the expansion region 162. The reduction of the available cross-sectional area of the inner conduit 146 may result in an increase in the localized pressure at the flow member 170. The amount of cross-sectional area occupied by the flow member 170 may vary. In some examples, the flow member 170 occupies less than 5% of the cross- sectional area of inner conduit 146. In some examples, the flow member 170 occupies between 5% and 10% of the cross-sectional area of inner conduit 146. In some examples, the flow member 170 occupies between 10% and 15% of the cross-sectional area of inner conduit 146. In some examples, the flow member 170 occupies between 15% and 20% of the cross-sectional area of inner conduit 146. And in some examples, the flow member 170 occupies between 20% and 25% of the cross-sectional area of inner conduit 146. [0041] Referring to FIG. 10, the exhaust expansion feature 160 creates a transition between the inner conduit 146 and the exhaust expansion region 162. In some examples, the exhaust expansion feature 160 forms a frustoconical tube centered about the central longitudinal axis 80. The exhaust expansion feature 160 extends between a first end 164 and a second end 166. The first end 164 of the exhaust expansion feature 160 is at and aligned with the second end 148 of the inner conduit 146. The second end 166 is a free end terminating in the exhaust expansion region 162 at a distance G from the exhaust substrate 134 (e.g., see FIG. 8). In certain examples, the exhaust expansion region 162 surrounds the exhaust expansion feature 160. In certain examples, the second end 166 is not attached to any other part of the exhaust treatment device 100. For example, the second end 166 of the exhaust expansion feature 160 may be spaced from the side wall 116. In some implementations, the exhaust expansion feature 160 extends through the divider wall 120 so that the first end 164 is connected to the inner conduit 146 upstream of the divider wall 120 and the free end 164 is disposed downstream of the divider wall 120. In other implementations, the first end 164 of the exhaust expansion feature 160 is connected to the downstream side of the divider wall 120. [0042] The exhaust expansion feature 160 extends radially outward of the central longitudinal axis 80 as the expansion feature 160 extends axially along the central longitudinal axis 80 from the second end 148 of the inner conduit 146 and toward the exhaust treatment substrate 134. The exhaust expansion feature 160 may extend outwardly at an angle X relative to the central longitudinal axis 80 (e.g., see FIG. 10). In some examples, angle X is less than 30 degrees. In some examples, angle X is between 30 and 45 degrees. In some examples, angle X is 45 degrees. In some examples, angle X is between 45 and 60 degrees. The distance G that the exhaust expansion feature 160 extends towards the exhaust treatment substrate 134 can vary. In some examples, the exhaust expansion feature 160 extends less than 25% of a distance F (e.g., see FIG. 8) between the inner conduit 146 and the exhaust treatment substrate 134 as measured along the central longitudinal axis 80. In some examples, the exhaust expansion feature 160 extends between 25% and 30% of the distance F between the inner conduit 146 and the exhaust treatment substrate 134 as measured along the central longitudinal axis 80. In some examples, the exhaust expansion feature 160 extends between 30% and 50% of the distance F between the inner conduit 146 and the exhaust treatment substrate 134 as measured along the central longitudinal axis 80. In some examples, the exhaust expansion feature 160 extends between 30 and 40 millimeters from the inner conduit 146 and towards the exhaust treatment substrate 134 as measured along the central longitudinal axis 80.

[0043] In certain examples, the exhaust expansion feature 160 is integral (e.g., beaded, welded, monolithically formed, etc.) to the inner conduit 146. In certain examples, the exhaust expansion feature 160 is integral to the divider wall 120. In certain examples, the exhaust expansion feature 160 is attached, adhered, or otherwise secured to the second end 148 of the inner conduit 146.

[0044] FIG. 11 shows an example exhaust flow path in the exhaust treatment device 100. The doser 156 directs reactant R into and through the mixing chamber 142 in a direction toward the inner conduit 146. In one example, the doser 156 injects the reactant R in a cone spray pattern. Exhaust gas E travels from the inlet 130, into the exhaust passage 150, through the mixing structure 152, and into the mixing chamber 142. The mixing structure 152 creates turbulence in the exhaust E to improve mixing. Mixing between the reactant R and the exhaust E begins in the mixing chamber 142 and continues as the exhaust E and reactant R continue to move through the mixing passage 144 within the inner conduit 146. Additional turbulence is introduced as the exhaust E passes through the flow member 170 at the mixing passage 144. When the exhaust E reaches the exhaust expansion feature 160 at the second end 148 of the inner conduit 146, the exhaust E is able to expand as it moves towards the exhaust treatment substrate 134. [0045] In certain examples, the flow member 170 and/or the exhaust expansion feature 160 may be used with other exhaust treatment devices, such as the exhaust treatment devices disclosed in U.S. Patent No. 9,598,999, the disclosure of which is hereby incorporated herein by reference in its entirety.

[0046] The various embodiments described above are provided by way of illustration only and should not be construed to limit the claims attached hereto. Those skilled in the art will readily recognize various modifications and changes that may be made without following the example embodiments and applications illustrated and described herein, and without departing from the full scope of the following claims.

[0047] Examples of the disclosure may be described according to the following aspects:

Aspect 1 : An exhaust treatment device comprising: an outer housing extending along a length between first and second end walls, the outer housing also including a side wall that extends along the length from the first end wall to the second end wall, the outer housing defining an interior space; a divider wall within the interior space of the outer housing, the divider wall being positioned at an intermediate location along the length of the outer housing, the divider wall separating the interior space of the outer housing into a first region and a second region, the first region being defined between the divider wall and the first end wall and the second region being defined between the divider wall and the second end wall; an inlet that is in fluid communication with the first region of the interior space; an outlet that is in fluid communication with the second region of the interior space; an exhaust treatment substrate mounted in the second region of the interior space; and an exhaust treatment and mixing assembly including: a mixing chamber disposed in the first region of the outer housing; an inner conduit disposed within the outer housing, the inner conduit defining a mixing passage that extends partially along the length of the outer housing, the mixing passage providing fluid communication between the mixing chamber and the second region of the interior space; an exhaust passage that surrounds the inner conduit, the exhaust passage being configured to direct exhaust flow from the inlet into the mixing chamber; a mixing structure for swirling the exhaust flow directed from the exhaust passage into the mixing chamber; a flow member disposed at the inner conduit, the flow member restricting a cross-sectional area of the mixing passage; and a dispenser mounting location provided at the first end wall of the outer housing for mounting a dispenser used for dispensing a reactant into the mixing chamber.

Aspect 2: The exhaust treatment device of Aspect 1, wherein the flow member is disposed at a second end of the inner conduit.

Aspect 3 : The exhaust treatment device of any of Aspects 1 or 2, wherein the flow member is a cross-bar arrangement having a plurality of members extending across the cross-sectional area of the mixing passage.

Aspect 4: The exhaust treatment device of Aspect 3, wherein each of the members extends outwardly from a central region and normal to a central longitudinal axis of the exhaust treatment device.

Aspect 5 : The exhaust treatment device of Aspects 3 or 4, wherein the cross-bar arrangement includes four members.

Aspect 6: The exhaust treatment device of Aspects 3, 4, or 5, wherein the flow member further includes a ring which surrounds ends of the four members and wherein the ring contacts an inner diameter of the inner conduit.

Aspect 7 : The exhaust treatment device of Aspect 6, wherein the cross-bar arrangement and ring are integral to each other. Aspect 8: The exhaust treatment device of any of the previous Aspects, wherein the flow member is configured to temporarily divide the exhaust flow into separate portions.

Aspect 9: The exhaust treatment device of any of the previous Aspects, wherein the flow member has a thickness that is less than its width.

Aspect 10: The exhaust treatment device of any of the previous Aspects, wherein the mixing passage further includes an exhaust expansion feature extending from a first end at the inner conduit and continuing to a second end that is axially spaced from the exhaust treatment substrate.

Aspect 11 : The exhaust treatment device of Aspect 10, wherein the exhaust expansion feature has a frustoconical tube shape.

Aspect 12: The exhaust treatment device of Aspects 10 or 11, wherein the exhaust expansion feature is spaced radially inwardly from the side wall.

Aspect 13: The exhaust treatment device of Aspects 10, 11, or 12, wherein the exhaust expansion feature extends between 25 and 30 percent of the distance between a second end of the inner conduit and an upstream face of the exhaust treatment substrate.

Aspect 14: The exhaust treatment device of any of Aspects 10-13, wherein the exhaust expansion feature extends outwardly from a second end of the inner conduit at an angle of 45 degrees relative to a central longitudinal axis.

Aspect 15: The exhaust treatment device of any of the previous Aspects, further comprising a reactant dispenser disposed at the dispenser mounting location.

Aspect 16: The exhaust treatment device of any of the previous Aspects, wherein the exhaust treatment substrate is a selective catalytic reduction catalyst. Aspect 17: The exhaust treatment device of any of the previous Aspects, wherein the flow member is centered about a central longitudinal axis.

Aspect 18: The exhaust treatment device of any of the previous Aspects, wherein the flow member includes four flow apertures configured to enable exhaust to flow therethrough.

Aspect 19: An exhaust treatment device comprising: an outer housing extending along a length between first and second end walls, the outer housing also including a side wall that extends along the length from the first end wall to the second end wall, the outer housing defining an interior space; a divider wall within the interior space of the outer housing, the divider wall being positioned at an intermediate location along the length of the outer housing, the divider wall separating the interior space of the outer housing into a first region and a second region, the first region being defined between the divider wall and the first end wall and the second region being defined between the divider wall and the second end wall; an inlet that is in fluid communication with the first region of the interior space; an outlet that is in fluid communication with the second region of the interior space; an exhaust treatment substrate mounted in the second region of the interior space; and an exhaust treatment and mixing assembly including: a mixing chamber positioned adjacent to the first end wall of the outer housing; a mixing passage defined by an inner conduit that extends partially along the length of the outer housing, the mixing passage providing fluid communication between the mixing chamber and the second region of the interior space; an exhaust passage that surrounds the inner conduit, the exhaust passage being configured to direct exhaust flow from the inlet into the mixing chamber; a mixing structure for swirling the exhaust flow directed from the exhaust passage into the mixing chamber; an exhaust expansion feature extending from a second region end of the inner conduit with a free end axially spaced from the exhaust treatment substrate and radially spaced from the side wall of the outer housing; and a dispenser mounting location provided at the first end wall of the outer housing for mounting a dispenser used for dispensing a reactant into the mixing chamber. Aspect 20: The exhaust treatment device of Aspect 19, wherein the exhaust expansion feature is a frustoconical tube.

Aspect 21 : The exhaust treatment device of any of Aspects 19 or 20, wherein the exhaust expansion feature is fixed to a second end of the inner conduit.

Aspect 22: The exhaust treatment device of any of Aspects 19, 20, or 21, wherein the exhaust expansion feature is integral to the inner conduit.

Aspect 23: The exhaust treatment device of any of Aspects 19-22, wherein the exhaust expansion feature extends outwardly from a second end of the inner conduit and towards the exhaust treatment substrate at an angle of 45 degrees about a longitudinal central axis.

Aspect 24: The exhaust treatment device of any of the Aspects 19-23, wherein the exhaust treatment device further includes a flow member disposed at the inner conduit, wherein the flow member is configured to restrict a cross-sectional area of the mixing passage.

Aspect 25: The exhaust treatment device of Aspect 24, wherein the flow member is disposed at a second end of the inner conduit.

Aspect 26: The exhaust treatment device of any of Aspects 24 or 25, wherein the flow member is a cross-bar arrangement having a plurality of members extending across the cross-sectional area of the mixing passage.

Aspect 27: The exhaust treatment device of Aspect 26, wherein each of the members extends outwardly from a central region and normal to a central longitudinal axis of the exhaust treatment device. Aspect 28: The exhaust treatment device of any of Aspects 26 or 27, wherein the crossbar arrangement includes four members.

Aspect 29: The exhaust treatment device of any of Aspects 26, 27, or 28, wherein the flow member further includes a ring which surrounds ends of the four members and wherein the ring contacts an inner diameter of the inner conduit.

Aspect 30: The exhaust treatment device of Aspect 29, wherein the cross-bar arrangement and ring are integral to each other.

Aspect 31 : The exhaust treatment device of any of Aspects 24-30, wherein the flow member is configured to temporarily divide the exhaust flow into separate portions.

Aspect 32: The exhaust treatment device of any of Aspects 24-31, wherein the flow member has a thickness that is less than its width.

Aspect 33: An exhaust treatment device comprising: an outer housing including opposite first and second end walls and a length that extends between the first and second end walls, the outer housing also including a side wall that extends along the length from the first end wall to the second end wall, the outer housing defining an interior space; a divider wall within the interior space of the outer housing, the divider wall being positioned at an intermediate location along the length of the outer housing, the divider wall separating the interior space of the outer housing into a first region and a second region, the first region being defined between the divider wall and the first end wall and the second region being defined between the divider wall and the second end wall; an inlet that is in fluid communication with the first region of the interior space; an outlet that is in fluid communication with the second region of the interior space; and an exhaust treatment and mixing assembly including: a mixing passage defined by an inner conduit that extends partially along the length of the outer housing, the mixing passage providing fluid communication between the first region and the second region of the interior space; a mixing structure positioned outside of a first region end of the inner conduit for swirling the exhaust flow directed from the inlet into the inner conduit; a flow member positioned within the inner conduit; and an exhaust expansion feature extending from a second region end of the inner conduit with a free end terminating toward the exhaust treatment substrate and the outer housing side wall.

Claims

WHAT IS CLAIMED IS:

1. An exhaust treatment device comprising: an outer housing extending along a length between first and second ends, the outer housing including a side wall that extends along the length from the first end to the second end, the outer housing defining an interior space; a divider wall disposed within the interior space of the outer housing, the divider wall being positioned at an intermediate location along the length of the outer housing, the divider wall separating the interior space of the outer housing into a first region and a second region, the first region being disposed upstream of the divider wall and the second region being disposed downstream of the divider wall; an inlet that is in fluid communication with the first region of the interior space; an outlet that is in fluid communication with the second region of the interior space; an exhaust treatment substrate disposed in the second region of the interior space; and an exhaust treatment and mixing assembly including: a mixing chamber disposed in the first region of the interior space; an inner conduit disposed within the outer housing, the inner conduit defining a mixing passage that extends partially along the length of the outer housing, the mixing passage providing fluid communication between the mixing chamber and the second region of the interior space; an exhaust passage disposed in the first region of the interior space, the exhaust passage surrounding the inner conduit, the exhaust passage being configured to direct exhaust flow from the inlet into the mixing chamber; a mixing structure disposed in the first region between the exhaust passage and the mixing chamber; a flow member disposed at the inner conduit, the flow member restricting a cross-sectional area of the mixing passage; and a dispenser mounting location provided at the first end of the outer housing.

2. The exhaust treatment device of claim 1 , wherein the flow member is disposed at a second end of the inner conduit.

3. The exhaust treatment device of any of claims 1 or 2, wherein the flow member is a cross-bar arrangement having a plurality of members extending across the cross- sectional area of the mixing passage.

4. The exhaust treatment device of claim 3, wherein each of the members extends outwardly from a central region and normal to a central longitudinal axis of the exhaust treatment device.

5. The exhaust treatment device of claim 3 or claim 4, wherein the cross-bar arrangement includes four members.

6. The exhaust treatment device of claim 5, wherein the flow member further includes a ring which surrounds ends of the four members and wherein the ring contacts an inner diameter of the inner conduit.

7. The exhaust treatment device of claim 6, wherein the cross-bar arrangement and the ring are integral to each other.

8. The exhaust treatment device of claim 1, wherein the flow member is configured to temporarily divide the exhaust flow into separate portions.

9. The exhaust treatment device of claim 1, wherein the flow member has a width extending along a transverse cross-dimension of the mixing passage and the flow member has a thickness extending from an upstream side of the flow member to a downstream side of the flow member, and wherein the thickness is less than the width.

10. The exhaust treatment device of claim 1, wherein the mixing passage further includes an exhaust expansion feature extending between a first end and a second end, the first end of the exhaust expansion feature being disposed at the inner conduit, and the second end of the exhaust expansion feature being axially spaced from the exhaust treatment substrate.

11. The exhaust treatment device of claim 10, wherein the exhaust expansion feature has a frustoconical tube shape.

12. The exhaust treatment device of claim 10, wherein the exhaust expansion feature is spaced radially inwardly from the side wall.

13. The exhaust treatment device of claim 10, wherein the exhaust expansion feature extends between 25 and 30 percent of a distance between a second end of the inner conduit and an upstream face of the exhaust treatment substrate.

14. The exhaust treatment device of claim 10, wherein the exhaust expansion feature extends outwardly from a second end of the inner conduit at an angle of 45 degrees relative to a central longitudinal axis of the inner conduit.

15. An exhaust treatment device comprising: an outer housing extending along a length between first and second ends, the outer housing including a side wall that extends along the length from the first end to the second end, the outer housing defining an interior space; a divider wall within the interior space of the outer housing, the divider wall being positioned at an intermediate location along the length of the outer housing, the divider wall separating the interior space of the outer housing into a first region and a second region, the first region being upstream of the divider wall and the second region being downstream of the divider wall; an inlet that is in fluid communication with the first region of the interior space; an outlet that is in fluid communication with the second region of the interior space; an exhaust treatment substrate mounted in the second region of the interior space; and an exhaust treatment and mixing assembly including: a mixing chamber disposed in the first region of the interior space; a mixing passage defined by an inner conduit that extends partially along the length of the outer housing, the mixing passage providing fluid communication between the mixing chamber and the second region of the interior space; an exhaust passage that surrounds the inner conduit, the exhaust passage being configured to direct exhaust flow from the inlet into the mixing chamber; a mixing structure for swirling the exhaust flow directed from the exhaust passage into the mixing chamber; an exhaust expansion feature extending from a base end to a free end, the base end being disposed at a second region end of the inner conduit, the free end being axially spaced from the exhaust treatment substrate and radially spaced from the side wall of the outer housing; and a dispenser mounting location provided at the first region of the interior space.

16. The exhaust treatment device of claim 15, wherein the exhaust expansion feature is a frustoconical tube.

17. The exhaust treatment device of claim 15, wherein the exhaust expansion feature is integral to the inner conduit.

18. The exhaust treatment device of claim 15, wherein the exhaust expansion feature extends outwardly from the second region end of the inner conduit and towards the exhaust treatment substrate at an angle of 45 degrees about a longitudinal central axis of the inner conduit.

19. An exhaust treatment device comprising: an outer housing including opposite first and second ends and a length that extends between the first and second ends, the outer housing also including a side wall that extends along the length from the first end to the second end, the outer housing defining an interior space; a divider wall within the interior space of the outer housing, the divider wall being positioned at an intermediate location along the length of the outer housing, the divider wall separating the interior space of the outer housing into a first region upstream of the divider wall and a second region downstream of the divider wall; an inlet that is in fluid communication with the first region of the interior space; an outlet that is in fluid communication with the second region of the interior space; and an exhaust treatment and mixing assembly including: a mixing passage defined by an inner conduit that extends partially along the length of the outer housing, the mixing passage providing fluid communication between the first region and the second region of the interior space; a mixing structure positioned upstream of the inner conduit for swirling exhaust flow directed from the inlet into the inner conduit; a flow member positioned within the inner conduit; and an exhaust expansion feature extending downstream of the inner conduit to a free end terminating before reaching an exhaust treatment substrate and the side wall of the outer housing.

20. The exhaust treatment device of claim 19, wherein the flow member is a cross-bar arrangement and a ring, the cross-bar arrangement including a plurality of members extending across a cross-sectional area of the mixing passage, and the ring surrounding distal ends of the plurality of members.