Patent Publication Number: US-10767537-B1

Title: Hydrocarbon injector deflector assembly for diesel exhaust system

Description:
INTRODUCTION 
     The present disclosure relates to exhaust systems and, more particularly, a hydrocarbon injector deflector for a diesel exhaust system of a vehicle. 
     Internal combustion engines produce particulate matter which is considered a waste byproduct of combustion and a concern to the environment. To reduce particulate matter exiting the exhaust system of a vehicle, a Diesel Particulate Filter (DPF) traps the soot/particulates in the exhaust and needs to be regenerated regularly at a high exhaust gas temperature of above 600 degC. Typically, the high exhaust temperature is generated in Diesel Oxidation Catalysts (DOC) by burning hydrocarbons (diesel fuel) vapors. The hydrocarbons are introduced into exhaust through a HydroCarbon Injector (HCl) at around 5 bar pressure. The HC comes out of HCl at a form of many HC droplets that need to be vaporized and mixed with exhaust flow before they get into the DOC. Improvements continue to be made to increase DPF regeneration efficiency yet maintaining competitive vehicle fuel efficiency. 
     Thus, while current diesel exhaust systems may achieve their intended purpose, there is a need for a new and improved system. 
     SUMMARY 
     According to one embodiment of the present disclosure, a hydrocarbon injector deflector for a diesel exhaust system is provided. In this embodiment, the deflector comprises a base plate having a first end linearly extending to a second end to define a first side and a second side. The base plate is arcuately formed such that the first side extends arcuately to the second side. The first end is disposed upstream of the exhaust system relative to the second end. 
     In this embodiment, the hydrocarbon deflector further comprises a frame connected to the second end of the base plate and extends therefrom at a first angle. The frame has an opening formed through the frame. Moreover, the window defines an outer wall having an inner side of the frame. The deflector further comprises a tab extending from the inner side at a second angle. 
     In one embodiment, the base plate comprises at least one slit formed therethrough. In this aspect, the slit formed through the base plate defines a wing for hydrocarbon droplet impingement. In another aspect, the at least one slit is a pair of grooves formed laterally between the first and second sides to define a pair of wings arcuately extending adjacent the second end of the base plate. 
     In another embodiment, the frame includes a first portion and a second portion. In this aspect, the first portion has a neck extending therefrom and is disposed on the second end of the base plate. Moreover, the second portion has at least one contact portion extending therefrom for mounting the deflector. 
     In one embodiment, the outer wall of the frame includes at least one cut formed thereon from the first portion to a length adjacent the second portion. The cut formed on the frame defines a strip extending from the second portion at a third angle. In this example, the at least one cut is a pair of cuts formed on the outer wall to define a pair of strips extending from the second portion of the frame at the third angle. 
     In another aspect of the present disclosure, a hydrocarbon injector deflector assembly for a diesel exhaust system of a vehicle having an exhaust flow is provided. The assembly comprises an exhaust column and a hydrocarbon injector disposed to and in fluid communication with the exhaust column. In this embodiment, the hydrocarbon injector is configured to introduce hydrocarbons to be mixed with the exhaust flow. The assembly further comprises a mixer disposed within the exhaust column downstream from the hydrocarbon injector. The assembly further comprises a Diesel Oxidation Catalyst (DOC) and a Diesel Particulate Filter (DPF) connect to and in fluid communication with the exhaust column. Moreover, the mixer is configured to mix HC droplets and exhaust flow and distribute them uniformly before the DOC. 
     In this aspect, the assembly further includes a hydrocarbon injector deflector comprising a base plate, a frame and a tab. In this embodiment, the base plate is disposed in the exhaust column between the hydrocarbon injector and the mixer. Moreover, the base plate has a first end linearly extending to a second end to define a first side and a second side. The base plate is arcuately formed such that the first side extends arcuately to the second side. The base plate is disposed adjacent the hydrocarbon injector. Moreover, the first end is disposed upstream relative to the second end. 
     The assembly further comprises a frame connected to the second end of the base plate and extending therefrom at a first angle. The frame has an opening or window formed therethrough. The window defines an outer wall having an inner side of the frame. The assembly further comprises a tab extending from the inner side of the frame at a second angle. 
     In one embodiment, the base plate comprises at least one slit formed therethrough. The slit defines a wing for hydrocarbon droplet impingement. The at least one slit is a pair of grooves formed laterally between the first and second sides to define a pair of wings arcuately extending adjacent the second end of the base plate. 
     In another embodiment, the frame includes a first portion and a second portion. The first portion has a neck extending therefrom and is disposed on the second end of the base plate. The second portion has at least one contact portion extending therefrom for mounting the deflector. In this embodiment, the outer wall of the frame includes at least one cut formed thereon from the first portion to a length adjacent the second portion, defining a strip extending from the second portion at a third angle. Moreover, the at least one cut is a pair of cuts formed on the outer wall to define a pair of strips extending from the second portion of the frame at the third angle. 
     In another embodiment, the frame is connected to the second end of the base plate and extends downstream therefrom at a first angle. Moreover, the first angle is between about 10 to about 15 degrees relative to a cross-section normal to the exhaust column for hydrocarbon droplet impingement and redistribution at low to medium exhaust flow. In one embodiment, the tab extends downstream from the inner side of the frame at a second angle, the second angle being between about 25 degrees and about 45 degrees relative to a cross-section normal to the exhaust column for hydrocarbon droplet impingement and redistribution at high exhaust flow. 
     In yet another aspect of the present disclosure, a vehicle having a diesel exhaust system with a hydrocarbon injector deflector assembly for exhaust flow is provided. In one embodiment, the vehicle comprises a chassis and a body supported by the chassis. The body includes a motor compartment and an occupant zone. Moreover, the vehicle further comprises a diesel exhaust system comprising an exhaust column and a hydrocarbon injector disposed to and in fluid communication with the exhaust column. The hydrocarbon injector is configured to introduce hydrocarbons to be mixed with the exhaust flow. The diesel exhaust system further comprises a mixer disposed within the exhaust column downstream from the hydrocarbon injector. In this example, the mixer is configured to distribute exhaust flow. The diesel exhaust system further comprises a Diesel Oxidation Catalyst (DOC) a diesel particulate filter (DPF) connect to and in fluid communication with the exhaust column. 
     In this aspect, the diesel exhaust system further comprises a hydrocarbon injector deflector. The deflector comprises a base plate, a frame and a tab. The base plate is disposed in the exhaust column between the hydrocarbon injector and the mixer. Moreover, the base plate has a first end linearly extending to a second end to define a first side and a second side. In this embodiment, the base plate is arcuately formed such that the first side extends arcuately to the second side. The base plate is disposed adjacent the hydrocarbon injector. Furthermore, the first end is disposed upstream relative to the second end. 
     In this example, the frame is connected to the second end of the base plate and extends therefrom at a first angle. The frame has a window opening formed therethrough wherein the window defines an outer wall having an inner side of the frame. Moreover, the tab extends from the inner side of the frame at a second angle. 
     In one embodiment, the base plate comprises at least one slit formed therethrough, defining a wing for hydrocarbon droplet impingement. Moreover, the frame includes a first portion and a second portion. The first portion has a neck extending therefrom and is disposed on the second end of the base plate. The second portion has at least one contact portion extending therefrom for mounting the deflector to the column. 
     In another embodiment, the outer wall of the frame includes at least one cut formed thereon from the first portion to a length adjacent the second portion, defining a strip extending from the second portion at a third angle. Moreover, the frame is connected to the second end of the base plate and extends downstream therefrom at a first angle. The first angle is between about 10 to about 15 degrees relative to a cross-section normal to the exhaust column for hydrocarbon droplet impingement and redistribution at low to medium exhaust flow. 
     In another embodiment, the tab extends downstream from the inner side of the frame at a second angle. The second angle is between about 25 degrees and about 45 degrees relative to a cross-section normal to the exhaust column for hydrocarbon droplet impingement and redistribution at high exhaust flow. 
     Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
         FIG. 1  is a perspective view of a hydrocarbon injector deflector in accordance with one embodiment of the present disclosure. 
         FIG. 2  is side view of the hydrocarbon injector deflector of  FIG. 1 . 
         FIG. 3  is a perspective view of a hydrocarbon injector deflector in accordance with another embodiment of the present disclosure. 
         FIG. 4A  is a schematic view of a hydrocarbon injector deflector assembly for an exhaust system of a vehicle according to an exemplary embodiment. 
         FIG. 4B  is an enlarged view of the hydrocarbon injector deflector assembly shown in circle  4 B in  FIG. 4A . 
     
    
    
     DETAILED DESCRIPTION 
     According to embodiments of the present disclosure, a hydrocarbon injector deflector for a diesel exhaust system of a vehicle having an exhaust flow is provided. The deflector is designed to have features that can distribute hydrocarbon droplets in the exhaust flow more uniformly at different exhaust flow rates across the exhaust flow cross-section before the hydrocarbon is mixed downstream by a mixer. A more uniform hydrocarbon distribution before the mixer enables a reduction in mixing/vaporization energy from the mixer and a reduction in pressure drop while still maintaining good mixing performances. 
       FIGS. 1 and 2  illustrate a hydrocarbon injector deflector  10  for a diesel exhaust system of a vehicle having an exhaust flow in accordance with one embodiment of the present disclosure. As shown, the deflector  10  comprises a base plate  12  having a first end  14  linearly extending to a second end  16  to define a first side  18  and a second side  20 . The base plate  12  is arcuately formed such that the first side  18  extends arcuately to the second side  20 . The first end  14  is to be disposed upstream of the exhaust system relative to the second end  16 . As discussed in greater detail below, the base plate  12  preferably allows for hydrocarbon droplet impingement/redistribution at low to medium exhaust flow rates. 
     In this embodiment, the hydrocarbon deflector  10  further comprises a frame  22  connected to the second end  16  of the base plate  12  and extends therefrom at a first angle  23 . As shown in  FIG. 1 , the frame  22  includes a first portion  24  and a second portion  26 . In this embodiment, the first portion  24  has a neck  28  extending therefrom and is disposed on or attached to the second end  16  of the base plate  12 . Moreover, the second portion  26  has at least one contact portion  30  extending therefrom for mounting the deflector  10  to the exhaust system. 
     Preferably, the frame  22  has an opening or window  32  formed through the frame  22 . Moreover, the window  32  defines an outer wall  34  having an inner side  36  of the frame  22 . As shown, the deflector  10  further comprises a tab  38  extending from the inner side at a second angle. As discussed in greater detail below, the frame  22  along with the tab  38  preferably allows for hydrocarbon droplet impingement/redistribution at relatively high exhaust flow rates. 
       FIG. 3  depicts a hydrocarbon injector deflector  40  for a diesel exhaust system of a vehicle having an exhaust flow in accordance with another embodiment of the present disclosure. As shown, the deflector  40  comprises a base plate  42  having a first end  44  linearly extending to a second end  46  to define a first side  48  and a second side  50 . The base plate  42  is arcuately formed such that the first side  48  extends arcuately to the second side  50 . The first end  44  is to be disposed upstream of the exhaust system relative to the second end  46 . As discussed in greater detail below, the base plate  42  preferably allows for hydrocarbon droplet impingement/redistribution at low to medium exhaust flow rates. 
     In this embodiment, the base plate  42  preferably comprises at least one slit  52  or groove formed therethrough. Preferably, the slit  52  is formed through the base plate  42  and defines a wing  54  for further enhanced hydrocarbon droplet impingement. As depicted in  FIG. 3 , the base plate  42  comprises a pair of slits formed laterally between the first and second sides to define a pair of wings arcuately extending adjacent the second end  46  of the base plate  42 . 
     In this embodiment, the hydrocarbon deflector  40  further comprises a frame  56  connected to the second end  46  of the base plate  42  and extends therefrom at a first angle  57 . As shown in  FIG. 3 , the frame  56  includes a first portion  58  and a second portion  60 . In this embodiment, the first portion  58  has a neck  62  extending therefrom and is disposed on or attached to the second end  46  of the base plate  42 . Moreover, the second portion  60  has at least one contact portion  64  extending therefrom for mounting the deflector  40  to the exhaust system. 
     Preferably, the frame  56  has an opening  66  or window formed through the frame  56 . Moreover, the window defines an outer wall  68  having an inner side  70  of the frame  56 . As shown, the outer wall  68  of the frame  56  includes at least one cut  72  formed thereon from the first portion  58  to a length adjacent the second portion  60 . The cut  72  formed on the frame  56  defines a strip  74  extending from the second portion  60  at a third angle. The third angle may be defined as an angle relative to the cross-section of the exhaust flow. The at least one cut  72  is preferably a pair of cuts formed on the outer wall  68  to define a pair of strips extending from the second portion  60  of the frame  56  at the third angle. 
     As shown, the deflector  40  further comprises a tab extending from the inner side  70  at a second angle. As discussed in greater detail below, the frame  56  along with the tab preferably allows for hydrocarbon droplet impingement/redistribution for relatively high exhaust flow rates. 
       FIGS. 4A and 4B  illustrate a hydrocarbon injector deflector  94  assembly  80  for a diesel exhaust system of a vehicle having an exhaust flow in accordance with another embodiment of the present disclosure. As shown, the assembly  80  comprises an exhaust column  86  and a hydrocarbon injector  88  disposed to and in fluid communication with the exhaust column  86 . In this embodiment, the hydrocarbon injector  88  is configured to introduce hydrocarbons to be mixed with the exhaust flow. The assembly  80  further comprises a mixer  90  disposed within the exhaust column  86  downstream from the hydrocarbon injector  88 . Moreover, the mixer  90  is configured to distribute exhaust flow. The assembly  80  further comprises a diesel particulate filter  92  disposed downstream from the mixer  90 . The diesel particulate filter  92  is connect to and in fluid communication with the exhaust column  86 . 
     In this embodiment, the assembly  80  further includes a hydrocarbon injector deflector  94  similar to the deflector shown in  FIG. 1 . As shown, the deflector  94  comprises a base plate  96 , a frame  106  and a tab. In this embodiment, the base plate  96  is disposed in the exhaust column  86  between the hydrocarbon injector  88  and the mixer  90 . Moreover, the base plate  96  has a first end  98  linearly extending to a second end  100  to define a first side  102  and a second side  104 . The base plate  96  is arcuately formed such that the first side  102  extends arcuately to the second side  104 . The base plate  96  is disposed adjacent the hydrocarbon injector  88 . Moreover, the first end  98  is disposed upstream relative to the second end  100 . 
     Preferably, the base plate  96  is disposed adjacent the injector  88  to provide hydrocarbon impingement as hydrocarbons are dispersed from the injector  88  thereby providing enhanced redistribution of hydrocarbons within the exhaust flow. It is to be understood that the base plate  96  is configured for impingement of hydrocarbons at low to medium exhaust flows. Thus, the base plate  96  preferably allows for hydrocarbon droplet impingement/redistribution at low to medium exhaust flow rates. 
     As shown, the assembly  80  further comprises a frame  106  connected to the second end  100  of the base plate  96  and extending therefrom at a first angle  107 . In this embodiment, the frame  106  includes a first portion  108  and a second portion  110 . The first portion  108  has a neck  112  extending therefrom and is disposed on the second end  100  of the base plate  96 . The second portion  110  has at least one contact portion  114  extending therefrom for mounting the deflector  94  to the exhaust column  86 . Preferably, the deflector  94  is mounted to the exhaust column  86  adjacent to the injector  88 . Moreover, the frame  106  has an opening or window  116  formed therethrough. The window  116  defines an outer wall  118  having an inner side  120  of the frame  106 . 
     As mentioned above, the frame  106  is connected to the second end  100  of the base plate  96  by way of the neck  112  and extends downstream therefrom at a first angle  107 . Moreover, the first angle  107  is preferably between about 10 to about 15 degrees relative to a cross-section normal to the exhaust column  86  for hydrocarbon droplet impingement and redistribution at low to medium exhaust flow. In this embodiment, the tab extends downstream from the inner side  120  of the frame  106  at a second angle  109 . Preferably, the second angle  109  is between about 25 degrees and about 45 degrees relative to a cross-section normal to the exhaust column  86  for hydrocarbon droplet impingement and redistribution at high exhaust flow. 
     Preferably, the frame  106  is positioned in the column  86  within an area of the exhaust flow cross-section such that anticipated high exhaust flow contacts the tab. The tab is configured to provide contact with hydrocarbons for enhanced hydrocarbon impingement within the exhaust flow. It is to be understood that the tab is configured for impingement of hydrocarbons at relatively high exhaust flows. Thus, the tab preferably allows for hydrocarbon droplet impingement/redistribution at high exhaust flow rates. 
     In one embodiment, the deflector  94  may be disposed adjacent the injector  88  such that the base plate  96  is positioned between about 15 millimeters (mm) and 45 mm therefrom, and the frame  106  is positioned between about 25 mm and 45 mm from the injector  88 . 
     The description of the present disclosure is merely exemplary in nature and variations that do not depart from the gist of the present disclosure are intended to be within the scope of the present disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the present disclosure.