Patent Publication Number: US-11655743-B2

Title: Systems and methods for reductant delivery in aftertreatment systems for internal combustion engines

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is a continuation of U.S. Pat. Ser. No. 17/070,513, filed Oct. 14, 2020, which is a continuation of U.S. patent application Ser. No. 16/144,683, filed Sep. 27, 2018, now U.S. Pat. No. 10,837,339. The contents of these applications are hereby incorporated by reference in their entirety. 
    
    
     TECHNICAL FIELD 
     The present application relates generally to systems and methods for reductant delivery in aftertreatment systems for internal combustion engines. 
     BACKGROUND 
     For internal combustion engines, such as diesel engines, nitrogen oxide (NO x ) compounds may be emitted in the engine exhaust. T 0  reduce NO x  emissions, a reductant may be dosed into the exhaust by a dosing system. The dosing system may include a housing positioned within an exhaust stream and a pipe positioned within the housing. 
     SUMMARY 
     In the above-described systems, the reductant may be provided through the pipe such that the pipe is substantially maintained at the temperature of the reductant. As the exhaust stream flows over the housing, the temperature of the housing increases while the temperature of the pipe is substantially maintained at the temperature of the reductant. As a result, a temperature gradient is created at junctures between the pipe and the housing. Stresses accumulate at the junctures due to the temperature gradient. These stresses can lead to failure of the dosing system. Accordingly, it is desirable to mitigate the accumulation of stresses at junctures between a housing and a pipe in a dosing system. 
     In one embodiment, a dosing lance assembly for an exhaust component includes a housing and a delivery conduit. The housing includes a plate, an endcap, and a pipe. The plate has a first channel. The endcap has a second channel. The pipe has a first end coupled to the plate and a second end coupled to the endcap. The delivery conduit has a first end coupled to the plate and a second end coupled to the endcap, such that reductant is flowable from the first channel to the second channel. When the housing is at an ambient temperature, (i) a length of the delivery conduit measured along the delivery conduit between a location at which the first end of the delivery conduit is coupled to the plate and a location at which the second end of the delivery conduit is coupled to the endcap is greater than (ii) a first distance between a location at which the first end of the pipe is coupled to the plate and a location at which the second end of the pipe is coupled to the endcap. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The details of one or more implementations are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the disclosure will become apparent from the description, the drawings, and the claims, in which: 
         FIG.  1    is a block schematic diagram of an example aftertreatment system; 
         FIG.  2    is a cross-sectional view of an example dosing lance assembly for use in an aftertreatment system, such as the example aftertreatment system shown in  FIG.  1   ; 
         FIG.  3    is a side view of an example delivery conduit for use in a dosing lance assembly, such as the example dosing lance assembly shown in  FIG.  2   ; 
         FIG.  4    is top view of the example delivery conduit shown in  FIG.  3   ; 
         FIG.  5    is a side view of another example delivery conduit for use in a dosing lance assembly, such as the example dosing lance assembly shown in  FIG.  2   ; 
         FIG.  6    is rear view of the example delivery conduit shown in  FIG.  5   ; 
         FIG.  7    is bottom view of the example delivery conduit shown in  FIG.  5   ; 
         FIG.  8    is a cross-sectional view of another example dosing lance assembly for use in an aftertreatment system, such as the example aftertreatment system shown in  FIG.  1   ; 
         FIG.  9    is a side view of another example delivery conduit for use in a dosing lance assembly, such as the example dosing lance assembly shown in  FIG.  2   ; 
         FIG.  10    is rear view of the example delivery conduit shown in  FIG.  9   ; 
         FIG.  11    is a perspective view of the example delivery conduit shown in  FIG.  9   ; 
         FIG.  12    is bottom view of the example delivery conduit shown in  FIG.  9   ; 
         FIG.  13    is a cross-sectional view of another example dosing lance assembly for use in an aftertreatment system, such as the example aftertreatment system shown in  FIG.  1   ; 
         FIG.  14    is a cross-sectional view of the dosing lance assembly shown in  FIG.  13   ; and 
         FIG.  15    is an exploded view of the dosing lance assembly shown in  FIG.  13   . 
     
    
    
     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 
     Following below are more detailed descriptions of various concepts related to, and implementations of, methods, apparatuses, and systems for delivering reductant through conduits within an aftertreatment system of an internal combustion engine system. The various concepts introduced above and discussed in greater detail below may be implemented in any of numerous ways, as the described concepts are not limited to any particular manner of implementation. Examples of specific implementations and applications are provided primarily for illustrative purposes. 
     I. Overview 
     Internal combustion engines (e.g., diesel internal combustion engines, etc.) produce exhaust gases that are often treated by a doser within an aftertreatment system. Dosers typically treat exhaust gases using a reductant. The reductant is typically provided from the doser into a dosing lance which distributes (e.g., doses, etc.) the reductant into an exhaust stream within an exhaust component. 
     Dosing lances are exposed to exhaust gases which cause heating of the dosing lances. This heating is distributed to components of the dosing lances. Reductant is provided through the dosing lances and cools components of the dosing lances. As a result, thermal gradients may exist between components that are cooled by the reductant and other components that are heated by the exhaust gases 
     A dosing lances may include a delivery conduit which is attached to the dosing lance and within which the reductant is provided. While the delivery conduit is cooled by the reductant, it is simultaneously heated by the exhaust gases. Thermal gradients at various locations, such as attachment points between the delivery conduit and the dosing lance, may become structurally compromised due to the accumulation of thermal stresses. These thermal gradients may be particularly pronounced in, for example, high horsepower applications. Accordingly, it is desirable to mitigate the accumulation of thermal stresses in delivery conduits in order to maintain the structural integrity of the dosing lance and delivery conduit. 
     Implementations described herein relate to a dosing lance assembly which includes a helical dosing conduit that facilitates expansion and contraction of components of the dosing lance assembly due to heat provided by exhaust gases. The helical dosing conduit has a length along the helical dosing conduit that is greater than a distance between locations where the helical dosing conduit is attached to the dosing lance assembly. As the dosing lance assembly is heated, the helical dosing conduit is straightened. Similarly, the helical dosing conduit becomes increasingly helical as the dosing lance assembly is cooled. In this way, the helical dosing conduit mitigates the accumulation of thermal stresses at attachment points of the helical dosing conduit to the dosing lance assembly. 
     II. Overview of Aftertreatment System 
       FIG.  1    depicts an aftertreatment system  100  having an example reductant delivery system  102  for an exhaust system  104 . The aftertreatment system  100  includes a particulate filter (e.g., a diesel particulate filter (DPF)  106 ), the reductant delivery system  102 , a decomposition chamber  108  (e.g., reactor, reactor pipe, etc.), a SCR catalyst  110 , and a sensor  112 . 
     The DPF  106  is configured to (e.g., structured to, able to, etc.) remove particulate matter, such as soot, from exhaust gas flowing in the exhaust system  104 . The DPF  106  includes an inlet, where the exhaust gas is received, and an outlet, where the exhaust gas exits after having particulate matter substantially filtered from the exhaust gas and/or converting the particulate matter into carbon dioxide. In some implementations, the DPF  106  may be omitted. 
     The decomposition chamber  108  is configured to convert a reductant into ammonia. The reductant may be, for example, urea, diesel exhaust fluid (DEF), Adblue®, an urea water solution (UWS), an aqueous urea solution (e.g., AUS 32 , AUS  40 , etc.), and other similar fluids. The decomposition chamber  108  includes a reductant delivery system  102  having a doser or dosing module  114  configured to dose the reductant into the decomposition chamber  108  (e.g., via an injector). In some implementations, the reductant is injected upstream of the SCR catalyst  110 . The reductant droplets then undergo the processes of evaporation, thermolysis, and hydrolysis to form gaseous ammonia within the exhaust system  104 . The decomposition chamber  108  includes an inlet in fluid communication with the DPF  106  to receive the exhaust gas containing NO x  emissions and an outlet for the exhaust gas, NO x  emissions, ammonia, and/or reductant to flow to the SCR catalyst  110 . 
     The decomposition chamber  108  includes the dosing module  114  mounted to the decomposition chamber  108  such that the dosing module  114  may dose the reductant into the exhaust gases flowing in the exhaust system  104 . The dosing module  114  may include an insulator  116  interposed between a portion of the dosing module  114  and the portion of the decomposition chamber  108  on which the dosing module  114  is mounted. The dosing module  114  is fluidly coupled to (e.g., fluidly communicable with, etc.) a reductant source  118 . The reductant source  118  may include multiple reductant sources  118 . The reductant source  118  may be, for example, a diesel exhaust fluid tank containing Adblue®. 
     A supply unit or reductant pump  120  is used to pressurize the reductant from the reductant source  118  for delivery to the dosing module  114 . In some embodiments, the reductant pump  120  is pressure controlled (e.g., controlled to obtain a target pressure, etc.). The reductant pump  120  includes a filter  122 . The filter  122  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  120 . For example, the filter  122  may inhibit or prevent the transmission of solids (e.g., solidified reductant, contaminants, etc.) to the internal components of the reductant pump  120 . In this way, the filter  122  may facilitate prolonged desirable operation of the reductant pump  120 . In some embodiments, the reductant pump  120  is coupled to a chassis of a vehicle associated with the aftertreatment system  100 . 
     The dosing module  114  and reductant pump  120  are also electrically or communicatively coupled to a controller  124 . The controller  124  is configured to control the dosing module  114  to dose the reductant into the decomposition chamber  108 . The controller  124  may also be configured to control the reductant pump  120 . The controller  124  may include a microprocessor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), etc., or combinations thereof. The controller  124  may include memory, which 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. The memory 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 controller  124  can read instructions. The instructions may include code from any suitable programming language. 
     The SCR catalyst  110  is configured to assist in the reduction of NO x  emissions by accelerating a NO x  reduction process between the ammonia and the NO x  of the exhaust gas into diatomic nitrogen, water, and/or carbon dioxide. The SCR catalyst  110  includes an inlet in fluid communication with the decomposition chamber  108  from which exhaust gas and reductant are received and an outlet in fluid communication with an end of the exhaust system  104 . 
     The exhaust system  104  may further include an oxidation catalyst (e.g., a diesel oxidation catalyst (DOC)) in fluid communication with the exhaust 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 gas. 
     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  114  may instead be positioned downstream of a turbocharger, upstream of a turbocharger, or integrated within the turbocharger. 
     The sensor  112  may be coupled to the exhaust system  104  to detect a condition of the exhaust gas flowing through the exhaust system  104 . In some implementations, the sensor  112  may have a portion disposed within the exhaust system  104 ; for example, a tip of the sensor  112  may extend into a portion of the exhaust system  104 . In other implementations, the sensor  112  may receive exhaust gas through another conduit, such as one or more sample pipes extending from the exhaust system  104 . While the sensor  112  is depicted as positioned downstream of the SCR catalyst  110 , it should be understood that the sensor  112  may be positioned at any other position of the exhaust system  104 , including upstream of the DPF  106 , within the DPF  106 , between the DPF  106  and the decomposition chamber  108 , within the decomposition chamber  108 , between the decomposition chamber  108  and the SCR catalyst  110 , within the SCR catalyst  110 , or downstream of the SCR catalyst  110 . In addition, two or more sensors  112  may be utilized for detecting a condition of the exhaust gas, such as two, three, four, five, or six sensors  112  with each sensor  112  located at one of the aforementioned positions of the exhaust system  104 . 
     The dosing module  114  includes a dosing lance assembly  126 . The dosing lance assembly  126  includes a delivery conduit (e.g., delivery pipe, delivery hose, etc.). The delivery conduit is fluidly coupled to the reductant pump  120  and a nozzle (e.g., for dosing into the decomposition chamber  108 , etc.). At least a portion of the dosing lance assembly  126  is located proximate (e.g., close, adjacent, etc.) to the exhaust system  104 . When the aftertreatment system  100  is operating and exhaust is provided to the aftertreatment system  100 , the temperature of components of the exhaust system  104  may rise (e.g., due to hot exhaust gases within the exhaust system, etc.). Heat from the exhaust system  104  may cause a temperature increase of the dosing lance assembly  126 . When exhaust is no longer provided to the exhaust system  104  (e.g., such as after an internal combustion engine associated with the aftertreatment system  100  has been turned off, etc.), the temperature of the dosing lance assembly  126  may decrease. As the temperature of the dosing lance assembly  126  changes, stresses (e.g., thermal stresses, etc.) may accumulate (e.g., accrue, collect, etc.) in the dosing lance assembly  126 . As will be explained in more detail herein, the delivery conduit of the dosing lance assembly  126  is configured to selectively deform to mitigate the accumulation of stresses in the dosing lance assembly  126 . 
     The reductant delivery system  102  also includes an air pump  128 . The air pump  128  draws air from an air source  130  (e.g., air intake, etc.). Additionally, the air pump  128  provides the air to the dosing module  114  via a conduit. The dosing module  114  is configured to mix the air and the reductant into an air-reductant mixture. The dosing module  114  is further configured to provide the air-reductant mixture into the decomposition chamber  108 . 
     III. Example Aftertreatment System Including an Auxiliary Delivery Conduit 
       FIG.  2    illustrates a cross-sectional view of an example dosing lance assembly  200 . The dosing lance assembly  200  may function as the dosing lance assembly  126  previously described. The dosing lance assembly  200  includes a housing  202 . The housing  202  includes a coupler  204  that is configured to be coupled (e.g., attached, affixed, fastened, welded, riveted, etc.) to an exhaust component  206 . In some embodiments, the exhaust component  206  is the decomposition chamber  108  previously described. In other embodiments, the exhaust component  206  is an exhaust conduit (e.g., tailpipe, manifold, etc.). The coupler  204  is disposed over an aperture  208  (e.g., hole, opening, etc.) in the exhaust component  206 . 
     The housing  202  also includes a plate  210  (e.g., endplate, endcap, etc.). The plate  210  is coupled to the coupler  204 . The plate  210  includes a first channel  212  (e.g., passageway, passage, etc.) and a second channel  214  (e.g., passageway, passage, etc.). The first channel  212  receives a first connector  216 , and the second channel  214  receives a second connector  218 . The first connector  216  receives air (e.g., from the air pump  128 , etc.) and provides the air through the plate  210  via the first channel  212 . Similarly, the second connector  218  receives reductant (e.g., from the reductant pump  120 , etc.) and provides the reductant through the plate  210  via the second channel  214 . 
     The housing  202  also includes a pipe  220  (e.g., airfoil pipe, pipe, cover, etc.). The pipe  220  has a first end that is coupled to the plate  210  over the first channel  212  and the second channel  214 . The pipe  220  extends through the coupler  204  and the aperture  208 , and into the exhaust component  206 . The housing  202  also includes an endcap  222 . The pipe  220  also has a second end that is coupled to the endcap  222 . In some embodiments, the endcap  222  extends substantially orthogonally from the pipe  220 . The housing  202  also includes a nozzle  224  positioned within the endcap  222 . The nozzle  224  is configured to provide an air-reductant mixture into the exhaust component  206 . 
     The dosing lance assembly  200  also includes a delivery conduit  226 . The delivery conduit  226  is coupled to the second channel  214 . The delivery conduit  226  extends through the pipe  220  and is coupled to a fitting  228  on the nozzle  224 . Specifically, the delivery conduit  226  is received within a channel  229  in the endcap  222  extending through the nozzle  224  and the fitting  228 . The delivery conduit  226  is configured to receive the reductant from the second connector  218  and to provide the reductant to the nozzle  224 . 
     The delivery conduit  226  includes a first end  230  and a second end  232 . The first end  230  is coupled to the plate  220  and the second end  232  is coupled to the endcap  222 . In various embodiments, the first end  230  is coupled to the second channel  214  and the second end  232  is coupled to the channel  229 . The delivery conduit  226  also includes a center section  234  contiguous with the first end  230  and the second end  232 . The delivery conduit  226  is rotatably disposed about (e.g., revolved around, etc.) or bent (e.g., turned, twisted, etc.), in a single bend or in multiple bends, relative to a channel central axis A upon which the second channel  214  is centered on. The center section  234  is bent in a single bend, multiple bends, or a single helix about the channel central axis A of the second channel  214 . As will be described in more detail herein, the center section  234  is configured to selectively extend and contract to mitigate the accumulation of stresses in the first end  230 , the second end  232 , and/or the housing  202 . 
     The dosing lance assembly  200  is associated with an internal combustion engine. The internal combustion engine is operable between a powered (e.g., on, operational, etc.) state and a non-powered (e.g., off, non-operational, etc.) state. In the powered state, the internal combustion engine produces exhaust gases that are provided through the exhaust component  206 . The exhaust gases are hot and transfer heat to the housing  202 , which further transfers heat to the delivery conduit  226 . 
     The temperature of the housing  202  varies depending upon the state of the internal combustion engine associated with the dosing lance assembly  200 . The temperature of the housing  202  may be an ambient temperature T 0  associated with an ambient environment surrounding the dosing lance assembly  200  when the internal combustion engine is in the non-powered state and has substantially cooled down. The ambient temperature T 0  is the temperature of the dosing lance assembly  200  absent any heating and/or cooling provided by the internal combustion engine associated with the dosing lance assembly  200 . The ambient temperature T 0  may be the temperature of air surrounding the dosing lance assembly  200 . In various applications, the ambient temperature T 0  may be, for example, between negative fifty-five degrees Celsius and fifty degrees Celsius, inclusive. The center section  234  is bent relative to the channel central axis A of the second channel  214  when the temperature of the housing  202  is the ambient temperature T 0 . 
     The temperature of the housing  202  may be a steady-state temperature T SS  when the internal combustion engine is in the powered state and has sufficiently warmed up. In various applications, the steady-state temperature T SS  may be, for example, between two-hundred degrees Celsius and five-hundred degrees Celsius, inclusive. In other applications, the steady-state temperature T SS  may be, for example, between two-hundred degrees Celsius and five-hundred and fifty degrees Celsius, inclusive. The center section  234  may be bent relative to the channel central axis A of the second channel  214  when the temperature of the housing  202  is the steady-state temperature T SS . The center section  234  may be at least partially disposed along the channel central axis A of the second channel  214  when the temperature of the housing  202  is the steady-state temperature T SS . 
     The temperature of the housing  202  may be a warm up temperature T WU  when the internal combustion engine is in the powered state but the temperature of the housing  202  is less than the steady-state temperature T SS . In various applications, the warm up temperature T WU  may be, for example, between negative fifty-five degrees Celsius and five-hundred degrees Celsius, inclusive. The center section  234  may be bent relative to the channel central axis A of the second channel  214  when the temperature of the housing  202  is the warm up temperature T WU . The center section  234  may be at least partially disposed along the channel central axis A of the second channel  214  when the temperature of the housing  202  is the warm up temperature T WU . 
     The temperature of the housing  202  may also be a cool down temperature T CD  when the internal combustion engine is in the non-powered state but the temperature of the housing  202  is less than the steady-state temperature T SS . In various applications, the cool down temperature T CD  may be, for example, between negative fifty-five degrees Celsius and five-hundred degrees Celsius, inclusive. The center section  234  may be bent relative to the channel central axis A of the second channel  214  when the temperature of the housing  202  is the cool down temperature T CD . The center section  234  may be at least partially disposed along the channel central axis A of the second channel  214  when the temperature of the housing  202  is the cool down temperature T CD . 
     
       
         
           
               
             
               
                 TABLE 1 
               
             
            
               
                   
               
               
                 Comparison of the state of the internal combustion 
               
               
                 engine and temperature of the housing 202. 
               
            
           
           
               
               
               
            
               
                   
                   
                 Example Temperatures 
               
               
                 State of Internal 
                 Temperature 
                 of the Housing 202 
               
               
                 Combustion Engine 
                 of the Housing 202 
                 [° C.] 
               
               
                   
               
               
                 Non-Powered 
                 T 0   
                 −55 ≤ T 0  ≤ 50 
               
               
                 Powered - Warm Up 
                 T 0  &lt; T WU  &lt; T SS   
                 −55 ≤ T WU  ≤ 500 
               
               
                 Powered - Steady-State 
                 T SS   
                 200 ≤ T SS  ≤ 500 
               
               
                 Non-Powered - Cool Down 
                 T 0  &lt; T CD  &lt; T SS   
                 −55 ≤ T CD  ≤ 500 
               
               
                   
               
            
           
         
       
     
     The center section  234  completes a cycle (e.g., thermal cycle, etc.) when the temperature of the housing  202  starts at the ambient temperature T 0  attains the steady state-temperature T SS , and returns back to the ambient temperature T 0 . As the temperature of the housing  202  changes, the center section  234  is configured to deform (e.g., rotate, translate, straighten, bend, expand, contract, etc.) relative to the channel central axis A of the second channel  214 . The ability of the center section  234  to deform is facilitated by the bent nature of the center section  234  when the delivery conduit  226  is at the ambient temperature T 0 . Deformation of the center section  234  mitigates accumulation of stresses (e.g., thermal stresses, etc.) in the first end  230 , the second end  232 , and/or the housing  202  that occur due to the change in temperature of the housing  202 . By mitigating the accumulation of stresses, the dosing lance assembly  200  is capable of withstanding a relatively large number of cycles of the center section  234 . 
     In contrast to the dosing lance assembly  200 , many conventional dosing lances include pipes for carrying reductant that are substantially straight at an ambient temperature. When a straight pipe is heated by exhaust gases, stresses accumulate in the straight pipe (e.g., at ends of the pipe, at attachment points of the pipe, etc.) because the straight pipe does not include any mechanism for effectively mitigating the accumulation of stresses. Accordingly, straight pipes are unable to withstand a relatively large number of cycles and may, for example, begin to crack and leak reductant. As a result, many conventional dosing lances are considerably less desirably than the dosing lance assembly  200 . 
     The delivery conduit  226  is substantially rigid. By “substantially rigid,” it is meant that the delivery conduit  226  maintains its shape even when not supported at both ends. The delivery conduit  226  is made of a substantially non-elastic material. The delivery conduit  226  may deform under pressure, but does so substantially without stretching of the material of the delivery conduit  226 . For example, the delivery conduit  226  may be made of solid metal. 
     In various embodiments, the housing  202 , the pipe  220 , the endcap  222 , and/or the nozzle  224  are made from a ferritic steel (e.g.,  439 ,  409 ,  410 L,  430 ,  430 Ti,  439 ,  441 ,  434 ,  436 ,  444 ,  446 ,  445 ,  447 , etc.) and the delivery conduit  226  is constructed from an austenitic steel (e.g.,  304 ,  304 L,  309 ,  310 ,  318 ,  316 ,  316 L,  316 Ti,  321 ,  200 , etc.). Such construction of the housing  202 , the pipe  220 , the endcap  222 , and/or the nozzle  224  may minimize cost of the dosing lance assembly  200  while mitigating corrosion of the delivery conduit  226 . In an example embodiment, the pipe  220  is constructed from  439  stainless steel and the delivery conduit  226  is constructed from  316  stainless steel. However, the housing  202 , the pipe  220 , the endcap  222 , the nozzle  224 , and/or the delivery conduit  226  may be constructed from, for example, aluminum, titanium, bronze, and other similar materials. In various embodiments, the delivery conduit  226  is not constructed from a non-metallic material (e.g., rubber, elastomer, etc.). 
     In various embodiments, the delivery conduit  226  is a one-piece construction (e.g., is not comprised of a plurality of components joined or coupled together, etc.). For example, the delivery conduit  226  may be formed from a single cylindrical pipe which is variously bent to form the delivery conduit  226 . Due to this one-piece construction, the delivery conduit  226  may be less prone to leaks and failure than flexible conduits (e.g., braided pipes, etc.). 
     IV. Example Delivery Conduits 
       FIGS.  3  and  4    illustrate the delivery conduit  226  according to an example embodiment. The delivery conduit  226  is a hollow cylinder and has an outer diameter d 0  and an inner diameter d i  defining a thickness t therebetween. The outer diameter d 0  of the delivery conduit  226  is substantially constant along the delivery conduit  226 . In an example embodiment, the outer diameter d 0  of the delivery conduit  226  is 6.35 mm. The inner diameter d i  of the delivery conduit  226  is substantially constant along the delivery conduit  226 . In an example embodiment, the inner diameter d i  of the delivery conduit  226  is 5.3975 mm. The thickness t of the delivery conduit  226  is substantially constant along the delivery conduit  226 . In an example embodiment, the thickness t of the delivery conduit  226  is 0.9525 mm. In another embodiment, the thickness t of the delivery conduit  226  is 0.81 mm (e.g., 20 gauge, etc.). 
     The delivery conduit  226  has a height H dc  between the first end  230  and the second end  232  along the channel central axis A of the second channel  214 . In an example embodiment the height H dc  of the delivery conduit  226  is 185.22 millimeters (mm). The delivery conduit  226  also has a height H cs  of the center section  234  along the channel central axis A of the second channel  214 . In an example embodiment, the height H cs  of the delivery conduit  226  is 175.22 mm. 
     The delivery conduit  226  is defined by a conduit central axis B extending within the delivery conduit  226  along a center point of the delivery conduit  226 . The delivery conduit  226  is also defined by a bend distance (e.g., circumference, etc.) L b  from the conduit central axis B of the center section  234  from the channel central axis A of the second channel  214 . In this way, the central axis B of the center section  234  is at least partially offset from (e.g., separated from, etc.) the channel central axis A of the second channel  214 . The bend distance L b  is substantially constant along the center section  234 . In an example embodiment, the bend distance L b  is 6.85 mm. As the center section  234  straightens, the bend distance L b  decreases; as the center section  234  becomes increasingly helical, the bend distance L b  increases. 
     The delivery conduit  226  is also defined by a plurality of bend radii r b . In an example, each of the radii r b  is equal to 9.5 mm. In various embodiments, each of the radii r b  is equal to 1.5d 0 . Such radii r b  simplify manufacturing requirements (e.g., facilitate utilization of standard manufacturing equipment as opposed to customized manufacturing equipment, etc.) while facilitating desirable deformation of the center section  234  when the temperature of the housing  202  changes. T 0  form the delivery conduit  226 , the delivery conduit  226  may be bent using a computer numeric control (CNC) bender. Each of the radii r b  may be input by a user into the CNC bender and the CNC bender may form a blank conduit into the delivery conduit  226 . 
     The first end  230  includes a first substantially straight section  300  where the conduit central axis B is substantially coincident with the channel central axis A of the second channel  214 . The first substantially straight section  300  of the first end  230  has a height H fe . In an example embodiment, the height H fe  of the first substantially straight section  300  of the first end  230  is 5 mm. 
     The second end  232  includes a second substantially straight section  302  where the conduit central axis B is substantially coincident with the channel central axis A of the second channel  214 . The second substantially straight section  302  of the second end  232  has a height H se . In an example embodiment, the height H se  of the substantially straight section  302  of the second end  232  is 5 mm. 
     The delivery conduit  226  also has a helical length L es  along the conduit central axis B and therefore along the delivery conduit  226 . The helical length L es  of the delivery conduit  226  is measured between a location at which the first end  230  is coupled to the plate  210  and a location at which the second end  232  is coupled to the endcap  222  (e.g., the fitting  228 , the channel  229 , etc.). The helical length L es  of the center section  234  is determined by
 
 L   cs =√{square root over ( H   cs   2 +(2π L   b ) 2 )}  (1)
 
     In an example embodiment where the height H cs  of the center section  234  is 175.22 mm and the bend distance L b  is 6.85 mm, the helical length L es  of the delivery conduit  226  is
 
 L   cs =√{square root over (175.22 mm 2 +(2π*6.85 mm) 2 )}=180.43 mm  (2)
 
     The housing  202  is defined by a height H h  between a location at which a first end of the pipe  220  is coupled to the plate  210  and a location at which a second end of the pipe  220  is coupled to the endcap  222 . The height H h  of the housing  202  is a function of the temperature of the housing  202 . In some embodiments, the height H h  is equal to 175.22 mm when the housing  202  is at the ambient temperature T 0 . The height H h  is equal to the height H cs  of the center section  234  when the entirety of the first substantially straight section  300  is received in the second channel  214  and the entirety of the second substantially straight section  302  is received in the fitting  228 . Accordingly, the helical length L es  of the center section  234 , which is measured between a location at which the first end  230  is coupled to the plate  210  and a location at which the second end  232  is coupled to the endcap  222  (e.g., the fitting  228 , the channel  229 , etc.), is greater than a distance, the height H h , between a location at which a first end of the pipe  220  is coupled to the plate  210  and a location at which a second end of the pipe  220  is coupled to the endcap  222 . 
     The delivery conduit  226  may have various different dimensions such that the delivery conduit  226  is tailored for a target application. In various embodiments, these different dimensions have a parametric relationship substantially identical to the parametric relationship present in the dimensions mentioned above. 
     
       
         
           
               
             
               
                 TABLE 2 
               
             
            
               
                   
               
               
                 Dimensions associated with the dosing lance 
               
               
                 assembly 200 at the ambient temperature T 0 . 
               
            
           
           
               
               
               
               
            
               
                   
                 Value of Dimension 
                 Parametric 
                 Value of Dimension 
               
               
                   
                 in an Example 
                 Relationship 
                 in Various 
               
               
                 Dimension 
                 Embodiment [mm] 
                 to d o   
                 Embodiments [mm] 
               
               
                   
               
            
           
           
               
               
               
               
            
               
                 d o   
                 6.35 
                 d o   
                  1-20 
               
               
                 H h   
                 175.22 
                 27.60d o   
                 27.60-552     
               
               
                 H dc   
                 185.22 
                 29.17d o   
                  29.17-583.40 
               
               
                 H cs   
                 175.22 
                 27.60d o   
                 27.60-552     
               
               
                 d i   
                 5.3975 
                  0.85d o   
                 0.85-17     
               
               
                 t 
                 0.9525 
                     0.15 d o   
                 0.15-3   
               
               
                 L b   
                 6.85 
                  1.08d o   
                 1.08-21.6 
               
               
                 r b   
                 9.5 
                 1.5d o   
                 1.5-30  
               
               
                 H fe   
                 5 
                  0.79d o   
                 0.79-15.8 
               
               
                 H se   
                 5 
                  0.79d o   
                 0.79-15.8 
               
               
                 H cs   
                 180.43 
                 28.41d o   
                 28.41-568.2 
               
               
                   
               
            
           
         
       
     
     As the housing  202  is heated (e.g., by exhaust gases within the exhaust component  206 , etc.), the housing  202  may deform. For example, each of the housing  202 , the pipe  220 , the endcap  222 , and/or the nozzle  224  may be displaced relative to the others of the housing  202 , the pipe  220 , the endcap  222 , and/or the nozzle  224  when the housing  202  is heated. This displacement results in a change in the height H h  of the housing  202 . The height H h  of the housing  202  is a function of the temperature Th of the housing  202 . 
     The change in the height H h  of the housing  202  is determined by
 
Δ H   h =α h   ΔT   h   H   h   (3)
 
where ΔT h  is the change in temperature of the housing  202  from an ambient temperature of the housing  202  (e.g., an average ambient temperature of various components of the housing  202 , etc.) associated with an ambient environment surrounding the dosing lance assembly  200  to a current temperature of the housing  202 , and where α h  is the coefficient of thermal expansion of the housing  202  (e.g., an average coefficient of thermal expansion of various components of the housing  202 , etc.). The change in the height H h  of the housing  202  may be determined when, for example, the internal combustion engine is warming up, at steady-state, or cooling down. The change in the height H h  of the housing  202  increases as the temperature of the housing  202  increases. Accordingly, the change in the height H h  of the housing  202  is greater when the internal combustion engine is at steady-state than when the internal combustion engine is warming up or cooling down.
 
     In one embodiment, the housing  202 , the pipe  220 , the endcap  222 , and the nozzle  224  are made from  439  stainless steel, such that α h  is 
             11   ⁢         μ   ⁢           ⁢   m     mK     .           
In this embodiment, the height H h  of the housing  202  is 175.22 mm and the average ΔT h  is 555° K (e.g., from −55° C. to 500° C., etc.). Therefore, the change in the height H h  of the housing  202  is:
 
                     Δ   ⁢           ⁢     H   h       =       11   ⁢       μ   ⁢           ⁢   m     mK     *   555   ⁢   °   ⁢           ⁢     K   .     *   175.22   ⁢           ⁢   mm   *       0.001   ⁢           ⁢   mm       1   ⁢           ⁢   μ   ⁢           ⁢   m         =       1069.718   ⁢       mm   2     m     *       1   ⁢           ⁢   m       1000   ⁢           ⁢   mm         =     1.07   ⁢           ⁢   mm                 (   4   )               
when the internal combustion engine is at steady-state. In this embodiment, the plate  210  and the fitting  228  are 1.07 mm further apart when the housing  202  is at the steady-state temperature T SS  than when the housing  202  is at the ambient temperature T 0 .
 
     As the height H h  of the housing  202  changes, the center section  234  is stretched and/or compressed. In this way, the height H cs  of the center section  234  is a function of the height H h  of the housing  202 . For example, as the height H h  increases (e.g., as the plate  210  is separated further from the fitting  228 , etc.), the plate  210  pulls on the first end  230  of the delivery conduit  226  and the fitting  228  pulls on the second end  232  of the delivery conduit  226 , thereby causing a corresponding increase in the height H cs  of the center section  234 . Stretching of the center section  234  is facilitated by the helical shape of the center section  234  because as the height H cs  of the center section  234  increases, the center section  234  straightens. Similarly, compression of the center section  234  is facilitated by the helical shape of the center section  234  because as the height H cs  of the center section  234  decreases, the center section  234  becomes increasingly helical in shape. The height H cs  of the center section  234  varies between
 
 H   h ( T   0 )≤ H   cs   ≤L   cs   (5)
 
where H h (T 0 ) is the height of the housing  202  when the housing  202  is at the ambient temperature T 0 . The center section  234  is configured to have a helical length L cs  that is equal to the height of the housing  202  when the housing  202  is at the steady-state temperature T SS . Therefore the helical length L cs  of the center section  234  is a function of the height H h  at the ambient temperature T 0 , the change in temperature of the housing  202  ΔT h  from the ambient temperature T 0  to the steady state current temperature of the housing  202 , and the coefficient of thermal expansion of the housing  202  α h . In various embodiments, a first location on the conduit central axis B is a first distance from a second location on the channel central axis A when the housing  202  is at the ambient temperature T 0 . In these embodiments, the first location on the conduit central axis B is a second distance, less than the first distance, from the second location on the channel central axis A when the housing  202  is at temperatures greater than the ambient temperature T 0 .
 
     Depending on the change in the height H h  of the housing  202  from the ambient temperature T 0  to the steady-state temperature T SS  the center section  234  may need to facilitate more or less stretching and compression. For example, if the change in the height H h  of the housing  202  from the ambient temperature T 0  to the steady-state temperature T SS  is relatively large, the center section  234  must facilitate a relatively large amount of stretching and compression. Accordingly, the height H cs  of the center section  234  and the bend distance L b  are functions of the change in the height H h  of the housing  202  from the ambient temperature T 0  to the steady-state temperature T SS . As the change in the height H h  of the housing  202  from the ambient temperature T 0  to the steady-state temperature T SS  increases, the height H cs  of the center section  234  and/or the bend distance L b  correspondingly increase. 
     As the housing  202  is heated by exhaust gases within the exhaust component  206 , the delivery conduit  226  is also heated. The housing  202  is structured to attain a maximum temperature T Max  when exhaust gases are provided through the exhaust component  206 . The maximum temperature T Max  is greater than the ambient temperature T 0 . The helical length L cs  of the center section  234  is determined by a function of the height H h  at the ambient temperature T 0 , the change in temperature of the housing  202  ΔT h  from the ambient temperature T 0  to the maximum temperature T Max , and the coefficient of thermal expansion of the housing  202  α h . The helical shape of the center section  234  is utilized because reductant flows through the delivery conduit  226 , thereby cooling the center section  234  relative to the housing  202 . The temperature of the delivery conduit  226  is less than the temperature of the housing  202  when the internal combustion engine is warming up, cooling down, and at steady state because of the cooling provided by the reductant. 
     The plate  210  is also structured to provide air into the pipe  220  such that the housing  202  and the delivery conduit  226  are cooled by the air. This air may be provided through the first channel  212 . This air may, for example, flow within the housing  202  thereby cooling an internal surface of the housing  202  while simultaneously cooling an external surface of the delivery conduit  226 . This cooling of the housing  202  functions to decrease the change in the height H h  of the housing  202  from the ambient temperature T 0  to the steady-state temperature T SS , thereby reducing the height H cs  and/or the bend distance L b  of the center section  234  because a smaller helical length L cs  of the center section  234  can be utilized. 
       FIGS.  5 - 7    illustrate the delivery conduit  226  according to another example embodiment. In this embodiment, the height H dc  of the delivery conduit  226  is 174.22 mm. The second end  232  is bent such that the second substantially straight section  302  is generally orthogonal to the conduit central axis B. The delivery conduit  226  of this embodiment may be implemented with a fitting  228  having a different configuration that that shown in  FIG.  2   . 
       FIG.  8    illustrates the dosing lance assembly  200  according to another example embodiment. In this embodiment, the dosing lance assembly  200  utilizes the delivery conduit  226  as shown in  FIGS.  5 - 7   . The dosing lance assembly  200  includes an air conduit  800  coupled to the exhaust component  206  about the aperture  208 . The air conduit  800  is coupled to elbow  802  which protrudes through the pipe  220  and is coupled to the nozzle  224 . The air conduit  800  receives air (e.g., from the first connector  216 , etc.) and routes the air within the pipe  220  around the delivery conduit  226 . The air conduit  800  is configured based on the delivery conduit  226  such that space between the delivery conduit  226  and the air conduit  800  is minimized. For example, the air conduit  800  may be a cylinder with an inner radius slightly larger than the bend distance L b  of the delivery conduit  226 . By routing the air with close proximity around the delivery conduit  226 , cooling of the delivery conduit  226  is maximized. The air conduit  800  may be coupled to the nozzle  224  such that the air is provided into the nozzle  224 . The endcap  222  may be coupled to the pipe  210  via brazed joints. Similarly, the pipe  210  may be coupled to the plate  210  using brazed joints. 
     As also shown in  FIG.  8   , the elbow  802  includes a first air passageway  804  and a second air passageway  806 . The first air passageway  804  and the second air passageway  806  receive air from the air conduit  800  and provide the air through the elbow  802  to the nozzle  224 . The first air passageway  804  and the second air passageway  806  may function to mix the air and the reductant in the nozzle  224 . The nozzle  224  may seal to the elbow  802  via a Grafoil® seal (e.g., gasket, O-ring, etc.). Similarly, the plate  210  may be configured to be attached to the exhaust component  206  via a bolted joint. 
       FIGS.  9 - 12    illustrate the delivery conduit  226  according to another example embodiment. In these embodiments, the delivery conduit  226  is bent in a single plane rather than a helix. By being bent only a single time, the delivery conduit  226  may experience less thermal stress on end welds (e.g., connections between the delivery conduit  226  and the plate  210 , connections between the delivery conduit  226  and the endcap  222 , etc.) than if the delivery conduit  226  was not bent at all. The arrangement of the delivery conduit  226  may minimize costs because only a relatively simple bending operation is required. In these embodiments, the height H se  of the second substantially straight section  302  of the second end  232  may be, for example, 15 mm, the outer diameter d 0  of the delivery conduit  226  may be, for example, 6.35 mm, the height H fe  of the first substantially straight section  300  of the first end  230  may be, for example, 15 mm, and the height H dc  of the delivery conduit  226  may be, for example, 183.37 mm. Furthermore, the delivery conduit  226  is defined by a small bend radius rbs at the junction of the center section  234  and each of the first end  230  and the second end  232  and a large bend radius r bl  at a midpoint of the center section  234 . In various embodiments, the small bend radius r bs  is 30 mm and the large bend radius r bl  is 250 mm. The delivery conduit  226  is also defined by a maximum bend distance d b  from an outermost edge of the first substantially straight section  300  to an outermost edge of the center section  234 . In various embodiments, the maximum bend distance db is 17.1 mm. In one embodiment, the thickness t of the delivery conduit  226  is 0.81 mm (e.g., 20 gauge, etc.). 
       FIGS.  13 - 15    illustrate the dosing lance assembly  200  according to another example embodiment. In this embodiment, the dosing lance assembly  200  utilizes the delivery conduit  226  as shown in  FIGS.  9 - 12   . The dosing lance assembly  200  does not include an air conduit similar to the air conduit  800 . The endcap  222  includes a threaded protrusion and the nozzle  224  is configured to be threaded onto the threaded protrusion. The threads may cover 6.8 mm on the endcap  222  and 6.8 mm on the nozzle  224 . In this way, the nozzle  224  may be sealed to the endcap  222  using a metal-to-metal seal (e.g., a 45 degree seal, etc.). In these embodiments, the endcap  222  includes a reductant passageway  1300  which receives the reductant from the channel  229  and provides the reductant to the nozzle  224 . 
     In the embodiments shown in  FIGS.  13 - 15   , the endcap  222  also includes a first air passageway  1400  and a second air passageway  1402 . The first air passageway  1400  and the second air passageway  1402  receive air from the pipe  220  and provide the air through the endcap  222  to the nozzle  224 . The air in the pipe  220  is pressurized. In various embodiments, the air in the pipe  220  is at approximately 45 pounds per square inch (PSI). The nozzle  224  has a 90 degree nozzle angle or a 70 degree nozzle angle. The nozzle  224  includes a plurality of holes (e.g., apertures, etc.)  1404  from which an air-reductant mixture is provided from the dosing lance assembly  200 . In various embodiments, the nozzle  224  includes six holes  1404 . The holes  1404  are symmetrically disposed about the nozzle  224  (e.g., at 60 degree increments about the nozzle  224 , etc.). The configuration of the first air passageway  1400 , the second air passageway  1402 , the reductant passageway  1300 , and the six holes  1404  creates an air curtain within the nozzle  224  which substantially prevents reductant from entering the air circuit of the dosing lance assembly  200  (e.g., entering the pipe  220  outside of the delivery conduit  226 , etc.). 
     In the embodiments shown in  FIGS.  13 - 15   , the plate  210  includes a protrusion  1302  which is configured to be received in the pipe  220 . The interaction between the protrusion  1302  and the pipe  220  is configured to arrest rotation of the pipe  220  relative to the plate  210 , and therefore relative to the exhaust component  206 . In this way, the protrusion  1302  may be a poka-yoke feature (e.g., an error-proof feature, etc.) for the dosing lance assembly  200 . In various embodiments, the pipe  220  and the protrusion  1302  are airfoil shaped (e.g., teardrop shaped, etc.). For example, the pipe  220  and the protrusion  1302  may each by shaped as a symmetric airfoil, a cambered airfoil, and/or shaped according to National Advisory Committee for Aeronautics (NACA) standards (e.g., NACA 2142, NACA 0015, NACA 0012, etc.). The airfoil shape of the pipe  220  may reduce boundary layer separation of exhaust gases encountering the pipe  220  (e.g., within the exhaust component  206 , etc.). As a result, the airfoil shape of the pipe  226  may facilitate less recirculation of the exhaust gases near the nozzle  224 , and therefore more desirable delivery of the reductant to the exhaust gases, than if the pipe  226  were not airfoil shaped. 
     The plate  210  may be configured to be attached to the exhaust component  206  via cooperation of a Marmon joint (e.g., a half Marmon joint, etc.) on the plate  210  and a V-band clamp. In this way, the dosing lance assembly  200  shown in  FIGS.  13 - 15    may be rapidly serviced. The endcap  222  may be coupled to the pipe  210  using tungsten inert gas (TIG) welds. Similarly, the pipe  210  may be coupled to the plate  210  using TIG welds. 
     In various embodiments, the endcap  222  is constructed from  316 L stainless steel, the nozzle  224  is constructed from Nitronic  60  alloy, the delivery conduit  226  is constructed from  316  L stainless steel, the pipe  220  is constructed from  439  stainless steel, and the plate  210  is constructed from  316 L stainless steel. The dosing lance assembly  200  may weigh, for example, 2.26796 kilograms (e.g., five pounds, etc.). 
     In the embodiments shown in  FIGS.  13 - 15   , the dosing lance assembly  200  is defined by a height H rp  from an exterior face of the plate  210  to a center axis of the reductant passageway  1300  and a height H ec  from an interior face of the plate  210  to a distal point (e.g., outermost point, etc.) of the end cap  222 . In various embodiments, the height H 1  is between 217.4 mm and 218.4 mm, inclusive and the height H ec  is 231.4 mm. Similarly, the dosing lance assembly  200  is defined by a distance d 0  from the outermost edge of the center section  234  to the outermost edge of the nozzle  224  and a distance den from the outermost edge of the center section  234  to the outermost edge of the endcap  222 . In various embodiments, the distance d 0  is 56.1 mm and the distance den is 33.51 mm. 
     IV. Construction of Example Embodiments 
     While this specification contains many specific implementation details, these should not be construed as limitations on the scope of what may be claimed but rather as descriptions of features specific to particular implementations. Certain features described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation can also be implemented in multiple implementations separately or in any suitable subcombination. Moreover, although features may be described as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can, in some cases, be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination. 
     As utilized herein, the terms “substantially,” “generally,” and similar terms are intended to have a broad meaning in harmony with the common and accepted usage by those of ordinary skill in the art to which the subject matter of this disclosure pertains. It should be understood by those of skill in the art who review this disclosure that these terms are intended to allow a description of certain features described and claimed without restricting the scope of these features to the precise numerical ranges provided. Accordingly, these terms should be interpreted as indicating that insubstantial or inconsequential modifications or alterations of the subject matter described and claimed are considered to be within the scope of the invention as recited in the appended claims. 
     As utilized herein, the term “helical” is intended to have a definition in harmony with that used in the art of geometric design. The term “helical” may refer to a cylindrical shape that is wrapped around another cylinder or cone. The term “helical” may refer to a shape in the form of a helix (e.g., single helix, double helix, etc.) or spiral. The term “helical” is not limited to a perfect helix and encompasses at least di minimus variations therefrom. 
     The terms “coupled,” “attached,” “fastened,” “fixed,” and the like, as used herein, mean the joining of two components directly or indirectly to one another. Such joining may be stationary (e.g., permanent) or moveable (e.g., removable or releasable). Such joining may be achieved with the two components or the two components and any additional intermediate components being integrally formed as a single unitary body with one another, with the two components, or with the two components and any additional intermediate components being attached to one another. 
     The terms “fluidly coupled,” “fluidly communicable with,” 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, 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. 
     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.