Systems and methods for sampling exhaust

Abstract

An aftertreatment unit for an exhaust aftertreatment system includes an aftertreatment housing and a sampling assembly. The aftertreatment housing defines a cavity and an exit opening. The sampling assembly is coupled to the aftertreatment housing. The sampling assembly includes a bowl and a sampler. The bowl is coupled to the aftertreatment housing on a first side of the exit opening. The bowl defines an exhaust aperture configured to provide exhaust into the cavity. The sampler is coupled to the aftertreatment housing at a location on a second side of the exit opening opposite the first side. The sampler includes a sampler tube and a first sampler aperture. The sampler tube is coupled to the bowl, extends into the cavity and across the exit opening, and is configured to provide the exhaust into the bowl. The first sampler aperture is configured to provide the exhaust into the sampler tube.

Description

SYSTEMSAND METHODS FOR SAMPLING EXHAUSTTECHNICAL FIELD

[0001] The present application relates generally to systems and methods for sampling exhaust in an exhaust aftertreatment system of an internal combustion engine.BACKGROUND

[0002] Nitrogen oxide (NOx) compounds are emitted in exhaust from internal combustion engines, such as diesel engines. It is desirable to reduce NOx emissions to comply with environmental regulations, for example. To reduce NOx emissions, a reductant may be dosed into the exhaust by a dosing system and within an aftertreatment system. The reductant facilitates conversion of a portion of the exhaust into non-NOx emissions, such as nitrogen (N2), carbon dioxide (CO2), and water (H2O), thereby reducing NOx emissions.

[0003] In some applications, it is desirable to sample a concentration of a constituent, such as NOx, N2, CO2, and / or H2O, in the exhaust produced by an internal combustion engine and treated by an aftertreatment system. By sampling the concentration of the constituent, operation of the aftertreatment system can be monitored. This sampling is obtained using a sensor around which the exhaust is provided.

[0004] The exhaust may be provided to the sensor via a sampling tube that extends into a cavity and across an exit opening in the cavity and routes the exhaust to the sensor. The sampling tube may disturb the flow of the exhaust and thereby increase backpressure and flow induced noise (e.g., turbulence, etc.) in the exhaust conduit. As a result, performance of the internal combustion engine may be negatively impacted.SUMMARY

[0005] In one embodiment, an aftertreatment unit for an exhaust aftertreatment system includes an aftertreatment housing and a sampling assembly. The aftertreatment housing defines a cavity and an exit opening. The sampling assembly is coupled to the aftertreatmenthousing. The sampling assembly includes a bowl and a sampler. The bowl is coupled to the aftertreatment housing on a first side of the exit opening. The bowl defines an exhaust aperture configured to provide exhaust into the cavity. The sampler is coupled to the aftertreatment housing at a location on a second side of the exit opening. The second side is opposite the first side. The sampler includes a sampler tube and a first sampler aperture. The sampler tube is coupled to the bowl. The sampler tube extends into the cavity and across the exit opening. The sampler tube is configured to provide the exhaust into the bowl. The first sampler aperture is configured to provide the exhaust into the sampler tube.

[0006] In another embodiment, an aftertreatment unit for an exhaust aftertreatment system includes an aftertreatment housing and a sampling assembly. The aftertreatment housing defines a cavity and an exit opening. The sampling assembly is for use with a NOx sensor. The sampling assembly includes a bowl, a sampler, and a NOx sensor. The bowl is coupled to the aftertreatment housing. The bowl defines an exhaust aperture configured to provide exhaust into the cavity. The sampler includes a sampler tube and a first sampler aperture. The sampler tube is coupled to the bowl. The sampler tube extends into the cavity and across the exit opening. The sampler tube is configured to provide the exhaust into the bowl. A portion of the sampler tube extending into the cavity and across the exit opening is arc-shaped. The first sampler aperture extends through the sampler tube. The first sampler aperture is configured to provide the exhaust into the sampler tube. The NOx sensor coupled is coupled to the aftertreatment housing. The NOx sensor coupling includes a NOx sensor coupling opening. The NOx sensor coupling is configured to receive an NOx sensor such that the NOx sensor projects through the NOx sensor coupling opening into the bowl.

[0007] In yet another embodiment, a sampling assembly includes a bowl, a sampler, and a first sensor coupling. The bowl is configured to couple to an aftertreatment housing defining a cavity and an exit opening. The bowl defines an exhaust aperture configured to provide exhaust into the cavity. The sampler includes a sampler tube and a plurality of sampler apertures. The sampler tube is coupled to the bowl. The sampler tube is configured to provide the exhaust into the bowl and configured to extend into the cavity and across the exit opening. A portion of the sampler tube configured to extend into the cavity and across the exit opening is arc-shaped. Theplurality of sampler apertures are configured to provide the exhaust into the sampler tube. The first sensor coupling is configured to couple to the aftertreatment housing. The first sensor coupling comprises a first sensor coupling opening configured to receive a first sensor such that the first sensor projects through the first sensor opening into the bowl.BRIEF DESCRIPTION OF THE DRAWINGS

[0008] 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:

[0009] FIG. 1 is a block schematic diagram of an example exhaust aftertreatment system;

[0010] FIG. 2 is a perspective view of an example exhaust aftertreatment system;

[0011] FIG. 3 is a front view of the exhaust aftertreatment system of FIG. 2;

[0012] FIG. 4 is a perspective view of an aftertreatment unit of the exhaust aftertreatment system of FIG. 2;

[0013] FIG. 5 is a perspective view of an aftertreatment housing of the aftertreatment unit of FIG. 4;

[0014] FIG. 6 is a cross-sectional view of aftertreatment housing of FIG. 5, taken along plane A- A;

[0015] FIG. 7 is a perspective view of a portion of the aftertreatment unit of FIG. 4;

[0016] FIG. 8 is another perspective view of the portion of the aftertreatment unit of FIG.7;

[0017] FIG. 9 is a top view of the portion of the aftertreatment unit of FIG. 7;

[0018] FIG. 10 is a cross-sectional view of the portion of the aftertreatment unit of FIG. 7, taken along plane C-C;

[0019] FIG. 11 is a view of Detail A of Figure 8;

[0020] FIG. 12 is a perspective view of a sampling assembly of the aftertreatment unit of FIG. 4;

[0021] FIG. 13 is a top view of the sampling assembly of FIG. 11;

[0022] FIG. 14 is a perspective view of a sampler tube of the sampling assembly of FIG.11;

[0023] FIG. 15 is a perspective view of the bowl of the sampling assembly of FIG. 11 ;

[0024] FIG. 16 is another perspective view of the bowl of the sampling assembly of FIG.11;

[0025] FIG. 17 is a perspective view of a sensor coupling of the sampling assembly of FIG. 11;

[0026] FIG. 18 is another perspective view of the sensor coupling body of the sampling assembly of FIG. 11;

[0027] FIG. 19 is a perspective view of a portion of another example aftertreatment unit of the exhaust aftertreatment system of FIG. 1 ;

[0028] FIG. 20 is a cross-sectional view of the portion of the aftertreatment unit of FIG. 19, taken along plane D-D; and

[0029] FIG. 21 is a perspective view of a portion of another example aftertreatment unit of the exhaust aftertreatment system of FIG. 1.

[0030] It will be recognized that some or all of 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 they will not be used to limit the scope or the meaning of the claims.DETAILED DESCRIPTION

[0031] Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, and for sampling exhaust in an exhaustaftertreatment system of an internal combustion engine. 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

[0032] Internal combustion engines (e.g., diesel internal combustion engines, etc.) produce exhaust that contains constituents, such as NOx, N2, CO2, and / or H2O. In some applications, an engine monitors various amount of these constituents. When the amount of a constituent is above or below a threshold (depending on the constituent), the internal combustion engine can, for example, alter performance of an exhaust aftertreatment system associated with the internal combustion engine (e.g., in order to reduce the amount of the constituent, etc.).

[0033] Monitoring of the exhaust may be achieved by sampling the exhaust within the exhaust aftertreatment system using various sensors. This sampling is performed using a sampler. Typical samplers extend into and across a pathway within which the exhaust flows. For example, some samplers include sampling tubes that extend across a diameter of the pathway within which the exhaust flows. As a result of extending across the pathway, these samplers may increase the backpressure experienced by the internal combustion engine and may increase the amount of noise in downstream exhaust, both of which may result in undesirable operation of the internal combustion engine.

[0034] Exhaust may contain liquid. Contact between liquid and a sensor may be undesirable. In order to account for liquid in exhaust, some samplers include water shields. These water shields may add increased cost, complexity, and manufacturing constraints to typical samplers. Additionally, these water shields may not consistently prevent contact between liquid and sensors.

[0035] Implementations described herein are related to a sampling assembly that samples exhaust using a sampler that protrudes into a cavity (e.g., a plenum, etc.) across a passage in which the exhaust flows, but without the sampling assembly extending upstream and into the passage or downstream and into the passage. As a result, the sampling assembly describedherein is capable of sampling exhaust without the increases in backpressure and downstream noise caused by typical samplers.

[0036] Furthermore, the protrusion of the sampler assembly away from an exit opening of the passage positions the sampler away from the passage and extends a length of the sampler. In this way and others described below, the transmission of liquid into the sampler assembly, and into the sensor, can be mitigated or prevented.II. Example Exhaust Aftertreatment System

[0037] FIG. 1 depicts an exhaust aftertreatment system 100 having an example reductant delivery system 102 for an exhaust conduit system 104. The exhaust aftertreatment system 100 includes the reductant delivery system 102, a particulate filter (e.g., a diesel particulate filter (DPF)) 106, a decomposition chamber 108 (e.g., reactor, reactor pipe, etc.), and a SCR catalyst 110.

[0038] The DPF 106 is configured to remove particulate matter, such as soot, from exhaust flowing in the exhaust conduit system 104. The DPF 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 DPF 106 may be omitted.

[0039] The decomposition chamber 108 is configured to convert a reductant into ammonia. The reductant may be, for example, urea, diesel exhaust fluid (DEF), Adblue®, a urea water solution (UWS), an aqueous urea solution (e.g., AUS32, etc.), and other similar fluids. The decomposition chamber 108 includes an inlet fluidly coupled to (e.g., fluidly configured to communicate with, etc.) the DPF 106 to receive the exhaust containing NOx emissions and an outlet for the exhaust, NOx emissions, ammonia, and / or reductant to flow to the SCR catalyst 110.

[0040] The reductant delivery system 102 includes a dosing module 112 (e.g., doser, etc.) configured to dose the reductant into the decomposition chamber 108 (e.g., via an injector). The dosing module 112 is mounted to the decomposition chamber 108 such that the dosing module 112 may dose the reductant into the exhaust flowing in the exhaust conduit system 104. Thedosing module 112 may include an insulator interposed between a portion of the dosing module 112 and the portion of the decomposition chamber 108 on which the dosing module 112 is mounted.

[0041] The dosing module 112 is fluidly coupled to a reductant source 114. The reductant source 114 may include multiple of the reductant sources 114. The reductant source 114 may be, for example, a diesel exhaust fluid tank containing Adblue®. A reductant pump 116 (e.g., supply unit, etc.) is used to pressurize the reductant from the reductant source 114 for delivery to the dosing module 112. In some embodiments, the reductant pump 116 is pressure controlled (e.g., controlled to obtain a target pressure, etc.). The reductant pump 116 includes a reductant filter 118. The reductant filter 118 filters (e.g., strains, etc.) the reductant prior to the reductant being provided to internal components (e.g., pistons, vanes, etc.) of the reductant pump 116. For example, the reductant filter 118 may inhibit or prevent the transmission of solids (e.g., solidified reductant, contaminants, etc.) to the internal components of the reductant pump 116. In this way, the reductant filter 118 may facilitate prolonged desirable operation of the reductant pump 116. In some embodiments, the reductant pump 116 is coupled to a chassis of a vehicle associated with the exhaust aftertreatment system 100.

[0042] The dosing module 112 includes an injector 120. The injector 120 is configured to dose the reductant into the exhaust (e.g., within the decomposition chamber 108, etc.). In some embodiments, the dosing module 112 may include multiple of the injectors 120 configured to dose the reductant into the exhaust. In some embodiments, the reductant 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 dosing module 112 via a conduit. In these embodiments, the dosing module 112 is configured to mix the air and the reductant into an air-reductant mixture and to provide the air-reductant mixture into the decomposition chamber 108. In other embodiments, the reductant delivery system 102 does not include the air pump 122 or the air source 124. In such embodiments, the dosing module 112 is not configured to mix the reductant with air.

[0043] The dosing module 112 and the reductant pump 116 are also electrically or communicatively coupled to a reductant delivery system controller 128. The reductant delivery system controller 128 is configured to control the dosing module 112 to dose the reductant into the decomposition chamber 108. The reductant delivery system controller 128 may also be configured to control the reductant pump 116.

[0044] The reductant 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 reductant 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.

[0045] In various embodiments, the reductant 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 reductant delivery system controller 128 are integrated into a single controller.

[0046] 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 displaydevice may provide an indication to a user (e.g., operator, etc.) of a status (e.g., operation, in need of service, etc.) of the reductant delivery system 102.

[0047] The decomposition chamber 108 is located upstream of the SCR catalyst 110. As a result, the reductant is injected upstream of the SCR catalyst 110 such that the SCR catalyst 110 receives a mixture of the reductant and exhaust. The reductant droplets undergo the processes of evaporation, thermolysis, and hydrolysis to form non-NOx emissions (e.g., gaseous ammonia, etc.) within the exhaust conduit system 104.

[0048] The SCR catalyst 110 is configured to assist in the reduction of NOx emissions by accelerating a NOx reduction process between the ammonia and the NOx of the exhaust into diatomic nitrogen, water, and / or carbon dioxide. The SCR catalyst 110 includes an inlet fluidly coupled to the decomposition chamber 108 from which exhaust and reductant are received and an outlet fluidly coupled to an end of the exhaust conduit system 104.

[0049] The exhaust aftertreatment system 100 may further include an oxidation catalyst (e.g., a diesel oxidation catalyst (DOC)) fluidly coupled to the exhaust conduit system 104 (e.g., downstream of the SCR catalyst 110 or upstream of the DPF 106) to oxidize hydrocarbons and carbon monoxide in the exhaust.

[0050] In some implementations, the DPF 106 may be positioned downstream of the decomposition chamber 108. For instance, the DPF 106 and the SCR catalyst 110 may be combined into a single unit. In some implementations, the dosing module 112 may instead be positioned downstream of a turbocharger or upstream of a turbocharger.

[0051] In various embodiments, the exhaust aftertreatment system 100 also includes a mixing assembly 138 (e.g., mixer, multi-stage mixer, etc.). The mixing assembly 138 is disposed between a decomposition chamber upstream portion 140 and a decomposition chamber downstream portion 142. Together, the decomposition chamber upstream portion 140, the mixing assembly 138, and the decomposition chamber downstream portion 142, form the mixing assembly 138. The dosing module 112 is coupled to the mixing assembly 138 and the injector 120 is configured to dose the reductant into the mixing assembly 138. As will be explained in more detail herein, the mixing assembly 138 functions to mix the exhaust receivedfrom the decomposition chamber upstream portion 140 with the reductant provided by the mixing assembly 138 and provide the decomposition chamber downstream portion 142 with exhaust that have been mixed with the reductant.

[0052] The exhaust aftertreatment system 100 also includes a sampling unit 144. In various embodiments, the sampling unit 144 is configured to sample the exhaust proximate the SCR catalyst 110. For example, a portion of the sampling unit 144 may be positioned proximate the SCR catalyst 110 to sample the exhaust exiting the SCR catalyst 110. However, in other embodiments, the sampling unit 144 is additionally or alternatively positioned proximate the DPF 106, or proximate the decomposition chamber 108. In still other embodiments, the sampling unit 144 is additionally or alternatively positioned downstream of the SCR catalyst 110 or upstream of the SCR catalyst 110 (e.g., upstream of the DPF 106, downstream of the DPF 106 and upstream of the decomposition chamber 108, downstream of the decomposition chamber 108 and upstream of the SCR catalyst 110, etc.).

[0053] In various embodiments, the sampling unit 144 includes a NOx sensor 146, a particulate sensor 148, and a temperature sensor 150. The NOx sensor 146 is configured to determine an amount (e.g., level, volume, etc.) of NOx in the exhaust flowing through the sampling unit 144. The NOx sensor 146 may be, for example, a Continental 2.8 NOx sensor, a Continental 2.0 NOx sensor, or a Bosch 4.0 NOx sensor. The particulate sensor 148 is configured to determine an amount of particulates in the exhaust flowing through the sampling unit 144. The temperature sensor 150 is configured to determine a temperature of the exhaust flowing through the sampling unit 144. The NOx sensor 146, the particulate sensor 148, and the temperature sensor 150 are configured to communicate with the reductant delivery system controller 128. For example, an amount of NOx determined by the NOx sensor 146 may be provided to the reductant delivery system controller 128, an amount of particulates determined by the particulate sensor 148 may be provided to the reductant delivery system controller 128, and a temperature determined by the temperature sensor 150 may be provided to the reductant delivery system controller 128. In some implementations, various of the NOx sensor 146, the particulate sensor 148, and the temperature sensor 150 are omitted.

[0054] In various embodiments, the outlet of the SCR catalyst 110 is fluidly coupled to an exit passage 152 (e.g., exhaust pipe, exhaust passage, etc.). The exit passage 152 may be fluidly coupled to the end of the exhaust conduit system 104 (e.g., an exhaust pipe, etc.). The exit passage 152 may define an exhaust flow-by area that the exhaust flows through while flowing through the exit passage 152.

[0055] While the exhaust aftertreatment system 100 has been shown and described in the context of use with a diesel internal combustion engine, it is understood that the exhaust aftertreatment system 100 may be used with other internal combustion engines, such as gasoline internal combustion engines, hybrid internal combustion engines, propane internal combustion engines, and other similar internal combustion engines.

[0056] Referring now to FIGS. 2 and 3, an example embodiment of the exhaust aftertreatment system 100 having the reductant delivery system 102 for the exhaust conduit system 104 is shown. The exhaust aftertreatment system 100 includes the reductant delivery system 102, the DPF 106, the decomposition chamber 108, the SCR catalyst 110, the sampling unit 144, the exit passage 152, and an aftertreatment unit 200. According to the example embodiment shown in FIGS. 2 and 3, the aftertreatment unit 200 includes the SCR catalyst 110 and the sampling unit 144. In other embodiments, the aftertreatment unit 200 includes other components of the exhaust aftertreatment system 100 (e.g., the DPF 106, the decomposition chamber 108, etc.) and the sampling unit 144.III. Example Sampling Assembly

[0057] The aftertreatment unit also includes a sampling assembly 300. As is explained in more detail herein, the sampling assembly 300 is configured to facilitate sampling of the exhaust flowing through the sampling assembly 300 such that an amount of a constituent, such as NOx, in the exhaust can be determined by a sensor (e.g., a sensor of the sampling unit 144, etc.). As is also explained in more detail herein, the sampling assembly 300 is structured such that transmission of liquid (e.g., water, reductant, fluid etc.) to a sensor element of the sensor is substantially prohibited (e.g., such that the sensor element is substantially isolated from any liquid entering the sampling assembly 300, etc.). In some applications, a sensor can becomeundesirable when a sensor element of the sensor is exposed to liquid. Therefore, the sampling assembly 300 may be capable of being more desirable than other systems which do not substantially prohibit transmission of liquid to a sensor element of a sensor.

[0058] The aftertreatment unit 200 also includes an aftertreatment housing 202 (e.g., a body, an aftertreatment body, etc.). According to the example embodiment shown in FIGS. 2 and 3 aftertreatment housing 202 is configured to receive the SCR catalyst 110. In other embodiments, the aftertreatment housing 202 is configured to receive other components of the exhaust aftertreatment system 100 (e.g., the decomposition chamber 108, the DPF 106, etc.) when the aftertreatment unit 200 includes the other components. The aftertreatment housing 202 includes a top portion 204, a center portion 206, and a bottom portion 208. In some embodiments, the top portion 204 is coupled to the center portion 206 and the center portion 206 is coupled to the bottom portion 208. In other embodiments, the top portion 204, the center portion 206, and the bottom portion are integrally formed (e.g., formed out of a single piece of metal, etc.).

[0059] The aftertreatment housing 202 includes an inlet opening 212 (e.g., an upstream inlet, etc.). The top portion 204 and the center portion 206 cooperatively define the inlet opening 212. The inlet opening 212 is configured to be coupled to an upstream exhaust conduit (e.g., a conduit of the decomposition chamber 108, a conduit of the DPF 106, etc.) and is configured to receive exhaust from an upstream component of the exhaust aftertreatment system 100 (e.g., the DPF 106, the decomposition chamber 108, etc.). In some embodiments, the inlet opening 212 is configured to provide the exhaust received from the upstream component of the exhaust aftertreatment system 100 to an upstream side of the SCR catalyst 110 positioned within the aftertreatment housing 202. In other embodiments, the inlet opening 212 is configured to provide the exhaust to an upstream side of the DPF 106 or the decomposition chamber 108. The inlet opening 212 may define an inlet flow-by area that the exhaust flows through while flowing through the inlet opening 212.

[0060] The aftertreatment housing 202 includes an exit opening 214 (e.g., a downstream outlet, etc.). The bottom portion 208 and the center portion 206 cooperatively define the exit opening 214. The exit opening 214 is configured to be coupled to a downstream exhaustconduit (e.g., the exit passage 152, etc.) and is configured to provide exhaust to a downstream component of the exhaust aftertreatment system 100 (e.g., the exit passage 152, etc.). In some embodiments, the exit opening 214 is configured to receive the exhaust from a downstream side of the SCR catalyst positioned within the aftertreatment housing 202. In other embodiments, the exit opening 214 is configured to receive the exhaust from a downstream side of the DPF 106 or the decomposition chamber 108 (e.g., when the aftertreatment unit 200 includes the DPF 106 or the decomposition chamber 108, etc.). The exit opening 214 may define an exit flow-by area that the exhaust flows through while flowing through the exit opening 214.

[0061] The aftertreatment housing 202 includes a cavity 216. The top portion 204, the center portion 206, and the bottom portion 208 cooperatively define the cavity 216. The cavity 216 is fluidly coupled with the inlet opening 212 and the exit opening 214 and is configured to provide exhaust from the inlet opening 212 to the exit opening 214. The cavity 216 may also be configured to receive the SCR catalyst 110 such that the exhaust is processed by the SCR catalyst 110 while flowing from the inlet opening 212 to the exit opening 214. In other embodiments, the cavity 216 is configured to receive the decomposition chamber 108 or the DPF 106 such that the exhaust is processed by the decomposition chamber 108 or the DPF 106 while flowing from the inlet opening 212 to the exit opening 214.

[0062] In various embodiments, the center portion 206 may define channels through the cavity 216. For example, the aftertreatment housing 202 may be configured to receive the SCR catalyst 110 and the SCR catalyst 110 may include multiple SCR catalyst components configured to be positioned in parallel. The channels defined by the center portion 206 through the cavity 216 may each be configured to receive one of the SCR catalyst components such that the SCR catalyst components may be positioned in parallel relative to the flow of the exhaust through the aftertreatment housing 202.

[0063] The cavity 216 may define a cavity flow-by area that the exhaust may flow through while flowing through the cavity 216. For example, the cavity flow-by area defined by the cavity 216 may be defined as an area contained inside of the center portion 206 in the cavity 216 along the plane B-B. In some embodiments, the cavity flow-by area may be reduced by theSCR catalyst components received by the aftertreatment housing 202. For example, the SCR catalyst components may include solid components that reduce the cavity flow-by area that the exhaust may flow through while flowing through the cavity 216. In various embodiments, the cavity flow-by area may be defined as an area contained inside of the top portion 204 or the bottom portion 208 in the cavity 216 along other planes that are perpendicular to plane A- A and extend through the top portion 204 or the bottom portion respectively.

[0064] The cavity flow-by area of the cavity 216 is larger than the exit flow-by area of the exit opening 214. In some embodiments, the cavity flow-by area of the cavity 216 is at least twice as large (e.g., three times as large, four times as large, etc.) as the exit flow-by area of the exit opening 214. In various embodiments, the cavity flow-by area of the cavity is, additionally or alternatively, larger than the inlet flow-by area of the inlet opening 212 or the exhaust flow- by area of the exit passage 152.

[0065] The relative size of the cavity flow-by area relative to the exit flow-by area, the inlet flow-by area, or the exhaust flow-by area may reduce the back pressure caused by the sampling assembly 300 when a portion (e.g., a sampler, etc.) of the sampling assembly 300 extends into the cavity 216 compared to when a portion of the sampling assembly 300 extends through the inlet opening 212, the exit opening 214, or the exit passage 152.

[0066] According to the example embodiment shown in FIGS. 4-6, the aftertreatment housing 202 also includes a sidewall 210. In some embodiments, the sidewall 210 extends from the bottom portion 208. In other embodiments, the sidewall 210 extends from the center portion 206 or the top portion 204. The sidewall 210 defines a plurality of sensor apertures 218. The sensor apertures 218 may each be configured to receive at least one of the sensors of the sampling unit 144 such that the sensors of the sampling unit 144 may extend into the cavity 216. In some embodiments, the sidewall 210 defines one of the sensor apertures 218 that is configured to receive each of the sensors of the sampling unit 144. For example, the sensor apertures 218 defined by the sidewall 210 may be configured to receive each of the NOx sensor 146, the particulate sensor 148, and the temperature sensor 150. In some embodiments, the sensor apertures 218 are generally circular.

[0067] The sampling assembly 300 (e.g., frame, structure, etc.) includes a bowl 310 (e.g., tube, pipe, etc.), a sensor coupling body 330 (e.g., a sensor bracket, a sensor mount, etc.), and a sampler 350 (e.g., a collection tube, a pipe, etc.). The bowl 310 is configured to be coupled to the sidewall 210 of the aftertreatment housing 202. The bowl 310 defines a bowl cavity 312 configured to receive exhaust from the sampler 350. In some embodiments, the bowl 310 and the sidewall 210 cooperatively define the bowl cavity 312 when the bowl 310 is coupled to the sidewall 210.

[0068] In some embodiments, the bowl 310 defines a bowl aperture 314 configured to receive the exhaust from the sampler 350. When the bowl 310 is coupled to the sidewall 210, the bowl 310 is positioned around (e.g., disposed around, etc.) the sensor apertures 218. In some embodiments, the bowl 310 is configured to be coupled to the sidewall 210 of the aftertreatment housing 202 on a first side of the exit opening 214 defined by the aftertreatment housing 202.

[0069] The bowl 310 includes a bowl interface surface 316 that interfaces with, or is located in confronting relation with, an inside surface of the sidewall 210 (e.g., an inside surface of the aftertreatment housing 202 partially defining the cavity 216, etc.) when the sampling assembly 300 is coupled to the aftertreatment housing 202. In some embodiments, the sidewall 210 to which the bowl 310 is coupled may be at least partially cylindrical or curved.

[0070] The bowl interface surface 316 of the bowl 310 may be curved to substantially match (e.g., within 2% of, within 5% of, etc.) a curvature of the sidewall 210. In this way, the bowl interface surface 316 may be mounted flush on the sidewall 210 (e.g., such that a gap between the bowl 310 and the sidewall 210 when the sampling assembly 300 is coupled to the aftertreatment housing 202 is substantially equal along the bowl 310, etc.) between the bowl 310 and the sidewall 210 and therefore decreases stress and strain on fasteners, welds, or rivets that couple the bowl 310 to the aftertreatment housing 202. In some embodiments, the bowl 310 is configured to be coupled to the aftertreatment housing 202 such that flow of the exhaust between the bowl 310 and the aftertreatment housing 202 is substantially prohibited.

[0071] The bowl 310 also defines an exhaust aperture 318 configured to provide the exhaust received from the sampler 350 into the cavity 216. In some embodiments, the bowl aperture 314 is positioned on a first side of the bowl 310 and the exhaust aperture 318 is positioned on a second side of the bowl 310 opposite the first side of the bowl 310 such that the exhaust received from the sampler 350 flows across the bowl 310 from the first side of the bowl 310 to the second side of the bowl 310 before flowing though the exhaust aperture 318 into the cavity 216.

[0072] A pressure differential between a first pressure of the exhaust within the bowl cavity 312 and a second pressure of the exhaust within the cavity 216 may substantially prevent backflow of the exhaust from the cavity 216 into the bowl cavity 312 through the exhaust aperture 318 (e.g., when the first pressure of the exhaust within the bowl cavity 312 is higher than the second pressure of the exhaust within the cavity 216, etc.). In various embodiments, the exhaust aperture 318 may be positioned proximate a bottom of the bowl 310 (e.g., a bottom of the bowl relative to a direction of gravity when the exhaust aftertreatment system 100 is configured to be operated, etc.) such that liquid accumulating in the bowl cavity 312 may drain through the exhaust aperture 318 into the cavity 216.

[0073] In some embodiments, the sampling assembly 300 also includes a mesh screen 320 coupled to the bowl 310 around the exhaust aperture 318. The mesh screen 320 includes openings configured to reduce a flow-by area of the exhaust through the exhaust aperture 318 to increase a back pressure of the exhaust in the bowl 310 such that the exhaust located in the cavity 216 does not flow backwards through the exhaust aperture 318 into the bowl 310. In some embodiments, the openings in the mesh screen 320 is also configured to prevent liquids or solids from flowing through the exhaust aperture 318 into the bowl 310 such that the liquids or solids do not flow through the exhaust aperture 318 to the sensors of the sampling unit 144. The size of the openings in the mesh screen 320 may be selected so as to impede the flow of liquids or solids through the exhaust aperture. For example, a diameter of each of the openings in the mesh screen 320 may be 0.015625 inches, 0.01 inches, 0.001 inches, 0.005 inches, or other similar values.

[0074] In some instances, liquid from the exhaust may accumulate (e.g., gather, pool, etc.) in the bowl cavity 312 due to gravity. To drain the liquid from the bowl cavity 312, the bowl 310 may define a drain aperture configured to provide any liquid that has accumulated in the bowl cavity 312 to the cavity 216.

[0075] The sensor coupling body 330 of the sampling assembly 300 is configured to receive the sensors of the sampling unit 144. The sensor coupling body 330 includes a first sensor coupling 332 configured to receive the NOx sensor 146 (e.g., a first sensor of the sampling unit 144, a NOx sensor coupling, etc.). The first sensor coupling 332 includes a first sensor aperture 334 (e.g., a sensor aperture, etc.) configured to receive and couple to the NOx sensor 146 (e.g., NOx sensor aperture, etc.).

[0076] The first sensor aperture 334 is defined by a first sensor axis Csi (e.g., a sensor axis, an NOx sensor axis, etc.). In some embodiments, the sampling assembly 300 may be configured such that an angle between the first sensor axis Csi and a direction of gravity is between 0 degrees and 80 degrees under normal operating conditions. For example, operation of the NOx sensor 146 may require the first sensor aperture 334 to be angled between 0 degrees and 80 degrees from the direction of gravity such that the NOx sensor 146 is positioned in an orientation that allows for the NOx sensor 146 to operate in an ideal manner.

[0077] In some embodiments, the first sensor aperture 334 includes threads that are configured to engage threads of the NOx sensor 146. In other embodiments, the first sensor aperture 334 defines other engagement interfaces (e.g., a press fit interface, an adhesive interface, etc.) configured to engage the NOx sensor 146. The first sensor aperture 334 may be configured to configured to be coupled to the NOx sensor 146 such that flow of the exhaust between the first sensor coupling 332 and the NOx sensor 146 is substantially prohibited.

[0078] The first sensor coupling 332 also includes a first sensor coupling opening 336 configured to receive the NOx sensor 146 (e.g., a NOx sensor coupling opening, etc.). The first sensor coupling opening 336 is defined by a sensor coupling opening axis Coi (e.g., a first coupling opening axis, an NOx sensor coupling axis, etc.). The sensor coupling opening axisCoi intersects the bowl cavity 312 of the bowl 310. In some embodiments, the sensor coupling opening axis Coi intersects the bowl aperture 314 of the bowl 310.

[0079] The first sensor coupling 332 may be coupled to the sidewall 210 of the aftertreatment housing 202 such that the first sensor coupling opening 336 at least partially aligns with one of the sensor apertures 218. For example, the first sensor coupling 332 may be coupled to the sidewall 210 of the aftertreatment housing 202 such that the sensor coupling opening axis Coi intersects a first of the sensor apertures 218. A first portion of the sidewall 210 defining the first of the sensor apertures 218 may be positioned between the first sensor coupling 332 and the bowl 310 and may extend around the first sensor coupling opening 336 such that a first portion of the aftertreatment housing 202 (e.g., the first portion of the sidewall 210, etc.) extends around the first sensor coupling opening 336 and between the first sensor coupling 332 and the bowl 310. In this way, the first sensor coupling opening 336 may be configured to provide a portion of the NOx sensor 146 to project through the first sensor coupling opening 336, through one of the sensor apertures 218 of the sidewall 210, and into the bowl cavity 312 of the bowl 310.

[0080] The first sensor axis Csi defining the first sensor aperture 334 and the sensor coupling opening axis Coi defining the first sensor coupling opening 336 are parallel, according to various embodiments. In other embodiments, the sensor coupling opening axis Coi is angularly offset by a first sensor offset angle (e.g., an angle, etc.) relative to first sensor axis Csi. In various applications, the first sensor offset angle may be substantially equal to 55°, 60°, 65°, or other similar values. In various applications, the first sensor offset angle is substantially equal to 10°-90°, inclusive.

[0081] In some embodiments, the sensor coupling body 330 includes a second sensor coupling 338 configured to receive an additional sensor of the sampling unit 144 (e.g., a second sensor of the sampling unit 144, the particulate sensor 148, the temperature sensor 150, a second of the NOx sensor 146, etc.). For example, the second sensor coupling 338 may be configured to receive the particulate sensor 148 or the temperature sensor 150.

[0082] In some embodiments, the second sensor coupling 338 and the first sensor coupling 332 are integrally formed (e.g., is attached to define a single structure, is monolithic, etc.). For example, the first sensor coupling 332 and the second sensor coupling 338 may be a single body configured to receive the NOx sensor 146 and the additional sensor of the sampling unit 144. In other embodiments, the first sensor coupling 332 and the second sensor coupling 338 may be separate bodies. In still other embodiments, the sensor coupling body 330 does not include the second sensor coupling 338 (e.g., the sampling unit 144 does not include the additional sensor of the sampling unit 144, etc.). In various embodiments, the sensor coupling body 330 include additional sensor couplings (e.g., a third sensor coupling, a fourth sensor coupling, etc.) configured to receive additional sensors of the sampling unit 144 (e.g., a third sensor of the sampling unit 144, a fourth sensor of the sampling unit 144, etc.).

[0083] The second sensor coupling 338 includes a second sensor aperture 340 configured to receive and couple to the additional sensor of the sampling unit 144. The second sensor aperture 340 is defined by a second sensor axis Cs2 (e.g., a particulate sensor axis, a temperature sensor axis, etc.). In some embodiments, the second sensor aperture 340 defines threads configured to engage threads of the additional sensor of the sampling unit 144. In other embodiments, the second sensor aperture 340 defines other engagement interfaces (e.g., a press fit interface, an adhesive interface, etc.) configured to engage the additional sensor of the sampling unit 144.

[0084] In various embodiments, the second sensor aperture 340 and the first sensor aperture 334 may be configured with same engagement interface or different engagement interfaces. The second sensor aperture 340 may be configured to configured to be coupled to the additional sensor of the sampling unit 144 such that flow of the exhaust between the second sensor coupling 338 and the additional sensor of the sampling unit 144 is substantially prohibited.

[0085] The second sensor coupling 338 also includes a second sensor coupling opening 342 configured to receive the additional sensor of the sampling unit 144 (e.g., a particulate sensor coupling opening, a temperature sensor coupling opening, etc.). The second sensor coupling opening 342 is defined by a second sensor coupling opening axis C02 (e.g., a temperaturesensor coupling axis, a particulate sensor coupling axis, etc.). The second sensor coupling opening axis C02 intersects the bowl cavity 312 of the bowl 310. In some embodiments, the second sensor coupling opening axis C02 intersects the bowl aperture 314 of the bowl 310.

[0086] The second sensor coupling 338 may be coupled to the sidewall 210 of the aftertreatment housing 202 such that the second sensor coupling opening 342 at least partially aligns with one of the sensor apertures 218. For example, the second sensor coupling 338 may be coupled to the sidewall 210 of the aftertreatment housing 202 such that the second sensor coupling opening axis C02 intersects a second of the sensor apertures 218. A second portion of the sidewall 210 defining the second of the sensor apertures 218 may be positioned between the second sensor coupling 338 and the bowl 310 and may extend around the second sensor coupling opening 342 such that a second portion of the aftertreatment housing 202 (e.g., the second portion of the sidewall 210, etc.) extends around the second sensor coupling opening 342 and between the second sensor coupling 338 and the bowl 310. In this way, the second sensor coupling opening 342 may be configured to provide a portion of the additional sensor of the sampling unit 144 to project through the second sensor coupling opening 342, through one of the sensor apertures 218 of the sidewall 210, and into the bowl cavity of the bowl 310.

[0087] The second sensor axis Cs2 defining the second sensor aperture 340 and the second sensor coupling opening axis C02 defining the second sensor coupling opening 342 are parallel, according to various embodiments. In other embodiments, the second sensor coupling opening axis C02 is angularly offset by a second sensor offset angle relative to the second sensor axis Cs2. In various applications, the second sensor offset angle may be substantially equal to 55°, 60°, 65°, or other similar values. In various applications, the second sensor offset angle is substantially equal to 10°-90°, inclusive.

[0088] The first sensor coupling 332 may be positioned upstream of the second sensor coupling 338 such that the NOx sensor 146 is positioned upstream of the additional sensor of the sampling unit 144, according to various embodiments. In other embodiments, the second sensor coupling 338 may be positioned upstream of the first sensor coupling 332 such that the NOx sensor 146 is positioned downstream of the additional sensor of the sampling unit 144. In various embodiments, the first sensor coupling 332 may be positioned upstream or downstreamof additional sensor couples such that the NOx sensor 146 is positioned upstream or downstream of the additional sensors of the sampling unit 144.

[0089] The sensor coupling body 330 also includes a coupling interface surface 344 that interfaces with, or is located in confronting relation with, an outside surface of the sidewall 210 (e.g., an outside surface of the sidewall 210 opposite the inside surface of the sidewall 210, an outside surface of the aftertreatment housing 202 opposite the inside surface of the aftertreatment housing 202, etc.) when the sampling assembly 300 is coupled to the aftertreatment housing 202.

[0090] The coupling interface surface 344 of the sensor coupling body 330 may be curved to substantially match the curvature of the sidewall 210. In this way, the coupling interface surface 344 may be mounted flush on the sidewall 210 (e.g., such that a gap between the sensor coupling body 330 and the sidewall 210 when the sampling assembly 300 is coupled to the aftertreatment housing 202 is substantially equal along the sensor coupling body 330, etc.) between the sensor coupling body 330 and the aftertreatment housing 202 and therefore decreases stress and strain on fasteners, welds, or rivets that couple the sensor coupling body 330 to the aftertreatment housing 202. In some embodiments, the sensor coupling body 330 is configured to be coupled to the aftertreatment housing 202 such that flow of the exhaust between the sensor coupling body 330 and the aftertreatment housing 202 is substantially prohibited.

[0091] The sampler 350 is configured to be coupled to the sidewall 210 of the aftertreatment housing 202 at a location on a second side of the exit opening 214, the second side of the exit opening 214 opposite the first side of the exit opening 214. In some embodiments, the sampler 350 is configured to be coupled to the sidewall 210 of the aftertreatment housing 202 at the location on the second side of the exit opening 214 such that flow of the exhaust between the sampler 350 and the sidewall 210 is substantially prohibited.

[0092] The sampler 350 includes a sampler tube 352 (e.g., tube, pipe, etc.) coupled to the bowl 310 and configured to provide exhaust into the bowl 310. The sampler tube 352 may be coupled to the bowl 310 at a first end 354 of the sampler tube 352. In some embodiments, thesampler tube 352 is configured to provide exhaust through the bowl aperture 314 defined by the bowl 310. In various embodiments, the sampler tube 352 is coupled to the sidewall 210 of the aftertreatment housing 202 at the location on the second side of the exit opening 214 at a second end 356 of the sampler tube 352 opposing the first end of the sampler tube 352. The sampler tube 352 extends into the cavity 216 and across the exit opening 214.

[0093] In some embodiments, a portion of the sampler tube 352 extending into the cavity 216 and across the exit opening 214 is arc-shaped (e.g., rounded, circular, is defined by a radius, etc.). For example, the portion of the sampler tube 352 extending into the cavity 216 may have a constant radius. As another example, the portion of the sampler tube 352 extending into the cavity 216 may have a varying radius. An outside radius of the sampler tube 352 proximate the bowl 310 and the sidewall 210 of the aftertreatment housing 202 on the second side of the exit opening 214 may be greater than an inside radius of the sampler tube 352 extending across the exit opening 214. In various embodiments, the sampler tube 352 does not extend through the exit opening 214. For example, the sampler tube 352 may be positioned entirely in the cavity 216 defined by the aftertreatment housing 202.

[0094] In various embodiments, the sampler tube 352 has a cross-section that is circular. In these embodiments, the sampler tube 352 is defined by a sampler diameter ds. In various applications, the sampler diameter dsmay be substantially equal to 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, or other similar values. In various applications, the sampler diameter dsis substantially equal to 5mm-20mm, inclusive.

[0095] In some embodiments, the sampler 350 also includes a bracket 358 coupled to the second end 356 of the sampler tube 352 that interfaces with, or is located in confronting relation with, an inside surface of the sidewall 210 at the location on the second side of the exit opening 214. In some embodiments, the bracket 358 is coupled to the aftertreatment housing 202 at the location on the second side of the exit opening 214. The bracket 358 may be curved to substantially match the curvature of the sidewall 210 at the location on the second side of the exit opening 214. In this way, the bracket 358 may be mounted flush on the sidewall 210 between the sampler 350 and the aftertreatment housing 202 and therefore decrease stress andstrain on fasteners, welds, or rivets that couple the sampler 350 to the aftertreatment housing 202 at the location on the second side of the exit opening 214.

[0096] Due to the sampler 350 extending into the cavity 216, the sampling assembly 300 is capable of operating with a pressure drop (e.g., a difference between a pressure of the exhaust gas upstream of the sampler 350 and a pressure of the exhaust gas downstream of the sampler 350, etc.) that is low compared to other sampling devices, such as those that extend across or into a passage within which exhaust gas flows. For example, the pressure drop of the sampling assembly 300 may be substantially equal to 5.20 kilopascal (kPa), which includes the SCR catalyst 110.

[0097] As utilized herein, a description of a first value being “substantially equal” to a second value describes the first value as being equal to the second value and the first value as being within 5%, inclusive, of the second value (e.g., the first value is equal to 105% of the second value, the first value is equal to 95% of the second value, etc.). In some applications, the pressure drop of the sampler 350 may be substantially equal to 1.30 kPa. In this way, the sampling assembly 300 may be significantly more desirable than other sampling devices which produce significant pressure drops (e.g., greater than 1.30 kPa, greater than 5.20 kPa including a pressure drop across an SCR catalyst, etc.).

[0098] The sampler tube 352 includes a plurality of sampler apertures 360 (e.g., holes, openings, etc.). As the exhaust flows from the inlet opening 212 through the cavity 216 to the exit opening 214, a portion of the exhaust may flow through any of the sampler apertures 360 and into the sampler tube 352. After the exhaust gas flows through one of the sampler apertures, the exhaust gas enters a sampler channel 362 (e.g., void, gap, etc.) of the sampler 350. The sampler channel 362 is formed inside of the sampler tube 352. The sampler channel 362 extends from the second end 356 of the sampler tube 352 to the first end 354 of the sampler tube 352. Exhaust flows from the sampler channel 362 into the bowl cavity 312. In other embodiments, the sampler tube 352 only includes a single of the sampler apertures 360.

[0099] In various embodiments, the sampler apertures 360 are each circular and defined by a sampler aperture diameter. In various applications, the sampler aperture diameter may besubstantially equal to 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, or other similar values. In various applications, the sampler aperture diameter is substantially equal to 0.25mm-5mm, inclusive. The sampler aperture diameter for each of the sampler apertures 360 may be the same for all of the sampler apertures 360 or may be different for some of the sampler apertures 360.

[0100] A first of the sampler apertures 360 (e.g., a first sampler aperture, etc.) may be defined by a first sampler aperture axis Cfsa(e.g., a sampler aperture axis, etc.) extending through the sampler tube 352. A second of the sampler apertures 360 (e.g., a second sampler aperture, etc.) may be defined by a second sampler aperture axis Cssa extending through the sampler tube 352. In some embodiments, a third of the sampler apertures 360 (e.g., a third sampler aperture, etc.) may be defined by a third sampler aperture axis Ctsa extending through the sampler tube 352. In some embodiments, the first sampler aperture axis Cssa, the second sampler aperture axis Cssa, and the third sampler aperture axis Ctsa (e.g., the sampler aperture axes, etc.) extend along a sampler aperture plane (e.g., a plane, plane C-C, etc.) etc.).

[0101] In various embodiments, the sampler aperture plane intersects the sampler channel 362 and the bowl cavity 312. In still other embodiments, the first sampler aperture axis Cssa and the second sampler aperture axis Cssa extend along the sampler plane (e.g., a first plane, etc.) and the third sampler axis Ctsa does not extend along the plane (e.g., the third sampler axis Ctsa is not parallel with the first sampler aperture axis Cssa and the second sampler aperture axis Cssa, etc.). In various embodiments, the sampler aperture plane intersects the exit opening 214. In various embodiments, the sampler aperture plane intersects the sampler tube 352 and the exit opening 214. In other embodiments, the sampler aperture plane intersects the inlet opening 212.

[0102] In some embodiments, the sampling assembly 300 is configured such that an angle between the sampler aperture plane and the first sensor axis Csi is between 10 degrees and 90 degrees. For example, the sampler aperture plane may be orientated such that the sampler aperture plane is substantially perpendicular to the direction of gravity during normal operation of the exhaust aftertreatment system 100 and the angle between the sampler aperture plane and the first sensor axis Csi may be between 10 degrees and 90 degrees to ensure that the NOx sensor 146 is at an angle between 100 degrees and 180 degrees relative to the direction ofgravity during the normal operation of the exhaust aftertreatment system. In some embodiments, the sampling assembly 300 is configured such that an angle between the sampler aperture plane and the second sensor axis CS2 is between 10 degrees and 90 degrees.

[0103] The flow of the exhaust is illustrated by solid arrows in FIG. 10. The sampler tube 352 and the bowl 310 interface about the first end 354 of the sampler tube 352 such that flow of the exhaust gas between the first end 354 of the sampler tube 352 and the bowl 310, aside from flow through the sampler channel 362 into the bowl cavity 312, is substantially prohibited. The exhaust first flows into the sampler channel 362 through one of the sampler apertures 360. The exhaust then flows along the sampler channel 362 in a direction from the second end 356 of the sampler tube 352 to the first end 354 of the sampler tube 352 and into the bowl cavity 312.

[0104] Inside the bowl cavity 312, the exhaust flows in a direction from the bowl aperture 314 towards the exhaust aperture 318 past the sensors of the sampling unit 144. For example, the exhaust may flow past a portion of the NOx sensor 146 configured to determine the amount of NOx in the exhaust gas. The exhaust may additionally or alternatively flow past a portion of the particulate sensor 148 configured to measure particulates in the exhaust or past a portion of the temperature sensor 150 configured to measure a temperature of the exhaust. The exhaust may then exit the bowl cavity through the exhaust aperture 318 of the bowl 310.

[0105] In some embodiments, the exhaust flowing through the sampler channel 362 and the bowl cavity 312 may contain liquid. The sampler channel 362 is defined by a length from the second end 356 of the sampler tube 352 to the first end 354 of the sampler tube 352. By increasing the length of the sampler tube 352, the temperature of the exhaust within the sampler channel 362 may be increased (e.g., due to prolonging the heating provided by the exhaust flowing across sampler tube 352, etc.). As the exhaust is heated, any liquid contained within the exhaust may evaporate. As a result, increasing the length of the sampler channel 362 can mitigate the transmission of liquid into the bowl cavity 312, and thus avoid contact between the liquid and the sensors of the sampling unit 144.

[0106] In some embodiments, the sampling assembly 300 includes thermal insulation that is positioned to provide thermal insulation (e.g., to reduce heat transfer from the exhaust gas toatmosphere within the sampling assembly 300, etc.) to any combination of the aftertreatment housing 202, the bowl 310, the sensor coupling body 330, or the sampler 350. The thermal insulation may function to increase the temperature of any combination of the aftertreatment housing 202, the bowl 310, the sensor coupling body 330, or the sampler 350which may mitigate the transmission of liquid into the NOx sensor 146.

[0107] While the sampling assembly 300 is shown and described as including the sampler 350, it is understood that the sampling assembly 300 may include additional samplers (e.g., an additional sampler, two additional samplers, etc.) similar to the sampler 350. Additionally, while the sampler 350 is shown and described as include multiple of the sampler apertures 360, it is understood that the sampler 350 may include a single of the sampler apertures 360.IV. Construction of Example Embodiments

[0108] 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.

[0109] 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 oralterations of the subject matter described and claimed are considered to be within the scope of the invention as recited in the appended claims.

[0110] 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.

[0111] 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, exhaust gas, liquid reductant, gaseous reductant, aqueous reductant, gaseous ammonia, etc., 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.

[0112] It is important to note that the construction and arrangement of the system 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 application, 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.

[0113] Also, the term “or” is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, 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, orX, 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 ofY, and at least one of Z to each be present, unless otherwise indicated.

[0114] Additionally, the use of ranges of values (e.g., W to P, etc.) herein are inclusive of their maximum values and minimum values (e.g., W to P includes W and includes P, etc.), unless otherwise indicated. Furthermore, a range of values (e.g., W to P, etc.) does not necessarily require the inclusion of intermediate values within the range of values (e.g., W to P can include only W and P, etc.), unless otherwise indicated.

Claims

WHAT IS CLAIMED IS:

1. An aftertreatment unit for an exhaust aftertreatment system, the aftertreatment unit comprising: an aftertreatment housing defining a cavity and an exit opening; and a sampling assembly coupled to the aftertreatment housing, the sampling assembly comprising: a bowl coupled to the aftertreatment housing on a first side of the exit opening, the bowl defining an exhaust aperture configured to provide exhaust into the cavity, and a sampler coupled to the aftertreatment housing at a location on a second side of the exit opening, the second side opposite the first side, the sampler comprising: a sampler tube coupled to the bowl, the sampler tube extending into the cavity and across the exit opening, the sampler tube configured to provide the exhaust into the bowl; and a first sampler aperture configured to provide the exhaust into the sampler tube.

2. The aftertreatment unit of claim 1, wherein a portion of the sampler tube extending into the cavity and across the exit opening is arc-shaped.

3. The aftertreatment unit of claim 1, wherein: the sampling assembly further comprises: a first sensor coupling coupled to the aftertreatment housing, the first sensor coupling comprising a first sensor coupling opening; the aftertreatment unit further comprises: a first sensor coupled to the first sensor coupling and projecting through the first sensor coupling opening into the bowl; and the bowl is coupled to the aftertreatment housing such that a first portion of the aftertreatment housing extends around the first sensor coupling opening and between the first sensor coupling and the bowl.

4. The aftertreatment unit of claim 3, wherein:the sampling assembly further comprises: a second sensor coupling coupled to the aftertreatment housing, the second sensor coupling comprising a second sensor coupling opening; the aftertreatment unit further comprises: a second sensor coupled to the second sensor coupling and projecting through the second sensor coupling opening into the bowl; and the bowl is coupled to the aftertreatment housing such that a second portion of the aftertreatment housing extends around the second sensor coupling opening and between the second sensor coupling and the bowl.

5. The aftertreatment unit of claim 1, further comprising a mesh screen coupled to the bowl around the exhaust aperture.

6. The aftertreatment unit of claim 1 , wherein: the first sampler aperture is defined by a first sampler aperture axis extending through the sampler tube; the sampler further comprises: a second sampler aperture defined by a second sampler aperture axis extending through the sampler tube, the second sampler aperture configured to provide the exhaust into the sampler tube, and a third sampler aperture defined by a third sampler aperture axis extending through the sampler tube, the third sampler aperture configured to provide the exhaust into the sampler tube; and the first sampler aperture axis, the second sampler aperture axis, and the third sampler aperture axis extend along a plane that intersects the sampler tube and the exit opening.

7. The aftertreatment unit of claim 6, wherein: a first end of the sampler tube is coupled to the bowl; and the sampler further comprises a bracket coupled to a second end of the sampler tube opposing the first end of the sampler tube, the bracket coupled to the aftertreatment housing at the location on the second side of the exit opening.

8. The aftertreatment unit of claim 7, wherein: the sampling assembly further comprises a sensor coupling coupled to the aftertreatment housing, the sensor coupling comprising: a sensor coupling opening, and a sensor aperture defined by a sensor axis, the sensor aperture configured to receive a sensor such that the sensor projects through the sensor aperture and the sensor coupling opening into the bowl; and an angle between the sensor axis and the plane is between 10 degrees and 90 degrees.

9. The aftertreatment unit of claim 1 , wherein: the first sampler aperture is defined by a first sampler aperture axis extending through the sampler tube; the sampler further comprises: a second sampler aperture defined by a second sampler aperture axis extending through the sampler tube, the second sampler aperture configured to provide the exhaust into the sampler tube, and a third sampler aperture defined by a third sampler aperture axis extending through the sampler tube, the third sampler aperture configured to provide the exhaust into the sampler tube; the first sampler aperture axis and the second sampler aperture axis extend along a plane; and the third sampler aperture axis does not extend along the plane.

10. An aftertreatment unit for an exhaust aftertreatment system, the aftertreatment unit comprising: an aftertreatment housing defining a cavity and an exit opening; and a sampling assembly for use with a NOx sensor, the sampling assembly comprising: a bowl coupled to the aftertreatment housing, the bowl defining an exhaust aperture configured to provide exhaust into the cavity, a sampler comprising:a sampler tube coupled to the bowl, the sampler tube extending into the cavity and across the exit opening, the sampler tube configured to provide the exhaust into the bowl, a portion of the sampler tube extending into the cavity and across the exit opening being arc-shaped; and a first sampler aperture extending through the sampler tube, the first sampler aperture configured to provide the exhaust into the sampler tube, and a NOx sensor coupling coupled to the aftertreatment housing, the NOx sensor coupling comprising a NOx sensor coupling opening, the NOx sensor coupling configured to receive an NOx sensor such that the NOx sensor projects through the NOx sensor coupling opening into the bowl.

11. The aftertreatment unit of claim 10, wherein: the NOx sensor coupling opening is defined by a sensor coupling opening axis extending through the NOx sensor coupling; and the NOx sensor coupling further comprises a NOx sensor aperture configured to receive the NOx sensor, the NOx sensor aperture defined by a sensor axis extending through the NOx sensor coupling, wherein an angle between the sensor coupling opening axis and the sensor axis is between 10 degrees and 90 degrees.

12. The aftertreatment unit of claim 10, wherein the sampling assembly further comprises a mesh screen coupled to the bowl around the exhaust aperture.

13. The aftertreatment unit of claim 10, wherein: the first sampler aperture is defined by a first sampler aperture axis extending through the sampler tube; the sampler further comprises: a second sampler aperture defined by a second sampler aperture axis extending through the sampler tube, the second sampler aperture configured to provide the exhaust into the sampler tube, anda third sampler aperture defined by a third sampler aperture axis extending through the sampler tube, the third sampler aperture configured to provide the exhaust into the sampler tube; and the first sampler aperture axis, the second sampler aperture axis, and the third sampler aperture axis extend along a plane.

14. The aftertreatment unit of claim 13, wherein: the NOx sensor coupling further comprises a NOx sensor aperture configured to receive the NOx sensor, the NOx sensor aperture defined by a sensor axis extending through the NOx sensor coupling; and an angle between the sensor axis and the plane is between 10 degrees and 90 degrees.

15. The aftertreatment unit of claim 10, wherein: the bowl is coupled to the aftertreatment housing on a first side of the exit opening; and the sampler tube is coupled to the aftertreatment housing at a location on a second side of the exit opening, the second side opposite the first side.

16. A sampling assembly comprising: a bowl configured to couple to an aftertreatment housing defining a cavity and an exit opening, the bowl defining an exhaust aperture configured to provide exhaust into the cavity; a sampler comprising: a sampler tube coupled to the bowl, the sampler tube configured to provide the exhaust into the bowl and configured to extend into the cavity and across the exit opening, a portion of the sampler tube configured to extend into the cavity and across the exit opening being arc-shaped; and a plurality of sampler apertures configured to provide the exhaust into the sampler tube; and a first sensor coupling configured to couple to the aftertreatment housing, the first sensor coupling comprising a first sensor coupling opening configured to receive a first sensor such that the first sensor projects through the first sensor coupling opening into the bowl.

17. The sampling assembly of claim 16, wherein:each of the sampler apertures are defined by a sampler aperture axis extending through the sampler tube; the first sensor coupling opening is defined by a sensor coupling opening axis; the sampler aperture axes extend along a plane; and an angle between the sensor coupling opening axis and the plane is between 10 degrees and 90 degrees.

18. The sampling assembly of claim 17, wherein the sampling assembly further comprises a second sensor coupling configured to couple to the aftertreatment housing, the second sensor coupling comprising a second sensor coupling opening configured to receive a second sensor such that the second sensor projects through the second sensor coupling opening into the bowl.

19. The sampling assembly of claim 16, further comprising a mesh screen coupled to the bowl around the exhaust aperture.

20. The sampling assembly of claim 16, wherein: the bowl is configured to couple to the aftertreatment housing on a first side of the exit opening; a first end of the sampler tube is coupled to the bowl; and the sampler further comprises a bracket coupled to a second end of the sampler tube opposing the first end of the sampler tube, the bracket configured to couple to the aftertreatment housing at a location on a second side of the exit opening, the second side opposite the first side.

Images