Abstract:
An exhaust treatment system for a vehicle includes an intake conduit adapted to receive pressurized intake air provided from a turbocharger compressor and supply the pressurized intake air to an internal combustion engine. An uninterrupted bypass conduit bypasses the internal combustion engine and includes upstream and downstream ends. The upstream end branches from the intake conduit. An exhaust conduit includes an upstream end adapted to receive exhaust from the internal combustion engine. An upstream end of a mixing tube is fixed to and in fluid communication with a downstream end of the exhaust conduit and the downstream end of the bypass conduit at a tubular joint, wherein the exhaust and the pressurized intake air are mixed within the mixing tube. An exhaust treatment device is in fluid communication with a downstream end of the mixing tube.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 12/041,943 filed on Mar. 4, 2008. The entire disclosure of the above application is incorporated herein by reference. 
     
    
     FIELD 
       [0002]    The present disclosure relates to an exhaust system and, more particularly, relates to a charged air bypass for an aftertreatment combustion air supply. 
       BACKGROUND 
       [0003]    The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. 
         [0004]    Vehicles can include aftertreatment devices for treating exhaust produced by an internal combustion engine. For instance, many vehicles include a diesel particulate filter that collects materials (e.g., soot) from the exhaust stream before being emitted from the vehicle, and these vehicles often include a burner that ignites injected fuel in order to reduce the collected materials. Also, some vehicles include a hydrocarbon injector (e.g., flame reformer, urea injector) that injects hydrocarbons into the exhaust stream in order to reduce undesirable substances, such as NOx, before the exhaust stream is emitted from the vehicle. 
         [0005]    These aftertreatment devices typically receive air from an air supply in order to function. For instance, burners receive air that is used to ignite fuel for reducing materials collected by an associated particulate filter. In most conventional systems, a pump is used to supply air to the aftertreatment device. This pump can be driven by the engine, or the pump can be independently driven. 
         [0006]    These conventional aftertreatment air supply systems can be relatively complex and can include a substantial number of components. Furthermore, the components can take up a substantial amount of space and can, therefore, be difficult to integrate into the vehicle. Additionally, these conventional air supply systems can cause parasitic losses to the engine system, which can reduce the efficiency of the engine system. 
       SUMMARY 
       [0007]    An engine system for a vehicle is disclosed. The vehicle includes an internal combustion engine, an intake fluid system that receives an intake fluid stream, and an exhaust fluid system that receives an exhaust stream from the engine. The vehicle also includes a turbocharger device including a compressor member that supplies a compressed fluid stream to the internal combustion engine and an energy supply member actuated by the exhaust stream. The vehicle further includes an aftertreatment device in operative communication with the exhaust stream to treat the exhaust stream. The engine system has a bypass fluid system that bypasses the internal combustion engine and includes an upstream end and a downstream end. The upstream end receives a portion of the compressed fluid stream from the compressor member, and the downstream end is in fluid communication with the exhaust fluid system downstream from the energy supply member. The bypass fluid system supplies the portion of the compressed fluid stream to the aftertreatment device. 
         [0008]    In another aspect, an engine system for a vehicle is disclosed. The engine system includes an internal combustion engine and an intake fluid system that receives an intake fluid stream. The engine system further includes an exhaust fluid system that receives an exhaust stream from the engine. Furthermore, the engine system includes a turbocharger device including a compressor member in operative communication with the intake fluid stream and an energy supply member in operative communication with the exhaust stream to be actuated thereby. The energy supply member transfers energy to the compressor member, the compressor member supplies a compressed fluid stream to the internal combustion engine. Moreover, the engine system includes an aftertreatment device in operative communication with the exhaust stream to treat the exhaust stream. The engine system additionally includes a bypass fluid system that bypasses the internal combustion engine and that includes an upstream end and a downstream end. The upstream end receives a portion of the compressed fluid stream from the compressor member, and the downstream end is in fluid communication with the exhaust fluid system downstream from the energy supply member. The bypass fluid system supplies the portion of the compressed fluid stream to the aftertreatment device. 
         [0009]    In still another aspect, a method of directing flow through an engine system is disclosed. The engine system includes an internal combustion engine, an intake fluid system, an exhaust fluid system, a turbocharger device including a compressor member and an energy supply member, an aftertreatment device, and a bypass fluid system that bypasses the internal combustion engine. The method includes receiving an intake fluid stream via the intake fluid system, receiving an exhaust stream from the engine via the exhaust fluid system, and actuating the energy supply member of the turbocharger device via the exhaust stream. The method also includes transferring energy from the energy supply member to the compressor member so as to supply a compressed fluid stream to the internal combustion engine. Furthermore, the method includes providing the aftertreatment device in operative communication with the exhaust stream and receiving a portion of the compressed fluid stream via the bypass fluid system. Additionally, the method includes directing flow of the portion of the compressed fluid stream through the bypass fluid system downstream from the energy supply member and to the aftertreatment device. 
         [0010]    In a further aspect, an engine system for a vehicle is disclosed. The engine system includes an internal combustion engine, an intake fluid system that receives an intake fluid stream, and an exhaust fluid system that receives an exhaust stream from the engine. The engine system also includes a turbocharger device including a compressor member in operative communication with the intake fluid stream and an energy supply member in operative communication with the exhaust stream to be actuated thereby. The energy supply member transfers energy to the compressor member, and the compressor member supplies a compressed fluid stream to the internal combustion engine. The engine system additionally includes a fluid cooler operatively coupled to the intake fluid system downstream of the compressor member to reduce a temperature of the compressed fluid stream. Moreover, the engine system includes an aftertreatment device in operative communication with the exhaust stream to treat the exhaust stream. The aftertreatment device includes a burner that reduces materials collected from the exhaust stream and/or a hydrocarbon injector that injects a hydrocarbon into the exhaust stream. The engine system further includes a controller and a bypass fluid system including an upstream end, a downstream end, and a bypass valve. The upstream end receives a portion of the compressed fluid stream from the turbocharger device, and the downstream end in fluid communication with the exhaust fluid system downstream from the energy supply member. The bypass fluid system supplies the portion of the compressed fluid stream to the aftertreatment device. Furthermore, the controller changes a configuration of the bypass valve to selectively change flow through the bypass fluid system. 
         [0011]    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. 
     
    
     
       DRAWINGS 
         [0012]    The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
           [0013]      FIG. 1  is a schematic diagram of a vehicle having an engine system according to the teachings of the present disclosure; 
           [0014]      FIG. 2  is a flowchart illustrating a method of operating the engine system of  FIG. 1 ; 
           [0015]      FIG. 3  is a schematic diagram of a vehicle with another embodiment of the engine system according to the teachings of the present disclosure; and 
           [0016]      FIG. 4  is a flowchart illustrating a method of operating the engine system of  FIG. 3 . 
       
    
    
     DETAILED DESCRIPTION 
       [0017]    The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features. 
         [0018]    Referring initially to  FIG. 1 , a vehicle  10  is illustrated having an engine system  12  according to various embodiments of the present disclosure. The engine system  12  includes an internal combustion engine  14 . The internal combustion engine  14  can be of any suitable type, such as a diesel engine, a gasoline-powered engine, etc. 
         [0019]    The engine system  12  further includes an intake fluid system, generally indicated at  16 , and an exhaust fluid system, generally indicated at  18 . As will be explained, the intake fluid system  16  generally receives an intake fluid stream  20  from outside the vehicle  10 , and the exhaust fluid system  18  generally receives an exhaust stream  22  from the engine  14 . In other words, the intake fluid stream  20  passes through the intake fluid system  16  to the engine  14 . The engine  14  produces the exhaust stream  22  as a product of combustion of fuel, and the exhaust stream  22  flows through the exhaust fluid system  18  and is emitted from the vehicle  10 . It will be appreciated that the intake and exhaust fluid system  16 ,  18  can include a plurality of hollow pipes, passages, and the like for directing flow of the respective fluids. 
         [0020]    Furthermore, the engine system  12  includes a turbocharger device  24 . The turbocharger device  24  can be of any suitable known type. In some embodiments, the turbocharger device  24  includes a compressor member  26 , an energy supply member  28 , and a coupling member  30 . In some embodiments, the compressor member  26  is in operative communication with the intake fluid stream  20 , and the energy supply member is in operative communication with the exhaust stream  22 . More specifically, in some embodiments, the compressor member  26  is disposed within the intake fluid system  16 , and the energy supply member  28  is disposed in the exhaust fluid system  18 . The energy supply member  28  and the compressor member  26  can be fixed to the coupling member  30 , and the turbocharger device  24  can be supported for rotation relative to the intake and exhaust fluid systems  16 ,  18 . Additionally, the compressor member  26  and the energy supply member  28  can each include a plurality of fins. In operation, as the intake fluid stream  20  flows through the intake fluid system  16 , the flow of the intake fluid stream is compressed by the compressor member  26 , such that the compressor member  26  supplies a compressed fluid stream  32  to the engine  14 . Also, flow of the exhaust stream  22  drivingly rotates the energy supply member  28 , and this energy of rotation is transferred to the compressor member  26  via the coupling member  30 . It will be appreciated that the turbocharger device  24  allows for a greater amount of air/fuel mixture to enter into the cylinders of the engine  14  to improve the efficiency of the engine  14 . 
         [0021]    The engine system  12  can also include a fluid cooler  33 . The fluid cooler  33  can be operatively coupled to the intake fluid system  16  downstream of the compressor member  26  of the turbocharger device  24 . In operation, the fluid cooler  33  reduces temperature of the compressed fluid stream  32  before entering the engine  14 . It will be appreciated that the fluid cooler  33  can be of any suitable known type. 
         [0022]    Additionally, the engine system  12  can include an aftertreatment device  34 . The aftertreatment device  34  can be in operative communication with the exhaust stream  22 . In other words, the aftertreatment device  34  can be in fluid communication with the exhaust stream  22  and disposed within the exhaust fluid system  18 . It will be appreciated that the aftertreatment device  34  can be of any suitable type for receiving at least a portion of the exhaust stream  22  and treating the exhaust stream  22 , such as a diesel particulate filter, a hydrocarbon injector, etc. 
         [0023]    In some embodiments represented by  FIG. 1 , the aftertreatment device  34  includes a diesel particulate filter  36  that filters particulate (i.e., soot) from the exhaust stream  22  before the exhaust stream  22  is emitted from the vehicle  10 . The diesel particulate filter  36  can also include a burner  38  and an injector  40 . At predetermined times, the injector  40  injects fuel, and the burner  38  ignites the fuel injected from the injector  40 , and the particulate matter collected by the diesel particulate filter  36  is reduced in a process known as “regeneration.” However, it will be appreciated that the aftertreatment device  34  can be of any suitable type for treating (e.g., reducing undesirable matter) from the exhaust stream  22 . 
         [0024]    The engine system  12  additionally includes a bypass fluid system  42 . Like the intake and exhaust fluid systems  16 ,  18 , the bypass fluid system  42  can include a plurality of pipes, passages, etc. The bypass fluid system provides fluid communication between the intake fluid system  16  and the exhaust fluid system  18  and bypasses the internal combustion engine  14 . Furthermore, the bypass fluid system  42  includes an upstream end  44  and a downstream end  46 . The upstream end  44  receives a portion of the compressed fluid stream  32  from the compressor member  26  of the turbocharger device  24 , and the downstream end  46  is in fluid communication with the exhaust fluid system  18  downstream from the energy supply member  28  of the turbocharger device  24 . As will be explained, the bypass fluid system  42  supplies the aftertreatment device  34  with the portion of compressed fluid stream  32  from the intake fluid system  16 . 
         [0025]    The bypass fluid system  42  can include a bypass valve  48 . The bypass valve  48  can be of any suitable type for selectively changing flow behavior through the bypass fluid system  42 . Also, the bypass valve  48  can be disposed in any suitable position relative to the bypass fluid system  42 . 
         [0026]    Moreover, the engine system  12  can include a controller  50 . The controller  50  can include circuitry, programmed logic, computer memory, and the like for changing a configuration of the bypass valve  48  (e.g., changing the position of the valve  48 ). The controller  50  can be in communication with the bypass valve  48  and the aftertreatment device  34 . As will be explained in greater detail, the controller  50  can change the configuration (e.g., the position) of the bypass valve  48  based on a predetermined operation schedule of the aftertreatment device  34 . 
         [0027]    Referring now to  FIG. 2 , a method  52  of operating the engine system  12  and directing fluid through the engine system  12  is illustrated. The method begins in decision block  54 , wherein it is determined whether conditions are met for regeneration of the diesel particulate filter  36 . In other words, decision block  54  involves determining whether the predetermined operation schedule calls for a regeneration of the diesel particulate filter  36 . It will be appreciated that the predetermined operation schedule can call for regeneration under any suitable vehicle conditions. For instance, the predetermined operation schedule can call for regeneration after a certain amount of miles have been driven, once pressure detected downstream of the aftertreatment device  34  is above a predetermined threshold, or the like. 
         [0028]    If decision block  54  is answered in the negative, the method  52  loops back to the start of the method  52 . However, if decision block  54  is answered in the affirmative, step  56  follows. 
         [0029]    In step  56 , the controller  50  transmits a signal causing the bypass valve  48  to move from a substantially closed position to an open position to begin flow through the bypass fluid system  42  to the aftertreatment device  34 . 
         [0030]    Then, in step  58 , regeneration of the diesel particulate filter  36  occurs. More specifically, the injector  40  injects a fuel into the fluid provided by the bypass fluid system  42 , and the burner  38  ignites the air/fuel mixture to reduce particulate collected by the diesel particulate filter  36 . It will be appreciated that the bypass fluid system  42  could provide fluid to the burner  38  in combination with the exhaust fluid system  18 , or the bypass fluid system  42  could provide fluid to the burner  38  independent of the exhaust fluid system  18  to enable regeneration of the aftertreatment device  34 . 
         [0031]    Then, in step  60 , the controller  50  transmits a signal, which causes the bypass valve  48  to move from the open position to the substantially closed position to substantially stop flow through the bypass fluid system  42 . Accordingly, it will be appreciated that the controller  50  controls the configuration and position of the bypass valve  48  such that flow through the bypass fluid system  42  is intermittent and such that flow through the bypass fluid system  42  occurs according to the predetermined regeneration schedule of the diesel particulate filter  36 . 
         [0032]    It will also be appreciated that the upstream end  44  of the bypass fluid system  42  is downstream from the fluid cooler  33 . As such, the compressed fluid stream  32  flowing through the bypass fluid system  42  is substantially cooled by the fluid cooler  33 . Accordingly, overheating and malfunction of the injector  40  is less likely. 
         [0033]    Referring now to  FIG. 3 , an engine system  112  of a vehicle  110  according to various other embodiments of the present disclosure is illustrated. It will be appreciated that the engine system  112  is substantially similar to the engine system  12  of  FIGS. 1 and 2 . It will also be appreciated that like components are indicated with like numerals increased by 100. 
         [0034]    The engine system  112  includes a bypass fluid system  142  with an upstream end  144  and a downstream end  146 . The upstream end  144  of the bypass fluid system  142  is in fluid communication with the intake fluid system  116  upstream of the cooler  133 . 
         [0035]    Also, in some embodiments, the engine system  112  includes and aftertreatment device  134 , such as a hydrocarbon injector  137  (e.g., flame reformer, urea injector). The hydrocarbon injector  137  can be of any suitable known type for injecting hydrocarbons into the exhaust stream  122  for reducing NOx emitted by the engine system  112 . 
         [0036]    Furthermore, the engine system  112  can include an emissions sensor  139  that detects an amount of an emission substance in the exhaust stream  122 . It will be appreciated that the emissions sensor  139  can be of any suitable known type, such as an NOx sensor that detects an amount of NOx in the exhaust stream  122 . The controller  150  is in communication with the bypass valve  148 , the aftertreatment device  134 , and the emissions sensor  139 . As will be described below, the controller  150  changes the configuration (e.g., the position) of the bypass valve  148  based on the amount of the emissions detected by the emissions sensor  139 . 
         [0037]    Referring now to  FIG. 4 , a method  170  for controlling the engine system  112  and directing flow through the engine system  112  is illustrated. The method  170  begins in step  172 , in which the emissions sensor  139  detects the level of NOx. Then, in step  172 , the controller  150  calculates a desired position of the bypass valve  148  based on the level of NOx detected by the emissions sensor  139 . 
         [0038]    Next, in step  176 , the controller  150  transmits a signal to change the position of the bypass valve  148  to match the desired position of the bypass valve  148  calculated in step  174 . In some embodiments, the position of the bypass valve  148  is changed in step  176  between a partially closed position and a fully open position. As such, flow is maintained substantially continuous, but the flow rate is changed through the bypass fluid system  142  in step  176 . In other words, flow rate through the bypass fluid system  142  varies as a function of the NOx output of the engine  114 , and the emissions sensor  139  provides feedback to the bypass valve  148  to adjust the amount of fluid flow through the bypass valve  148  to the hydrocarbon injector  137 . 
         [0039]    In some embodiments represented in  FIG. 3 , the upstream end  144  of the bypass fluid system  142  is in fluid communication with the intake fluid system  116  upstream of the fluid cooler  133  and downstream of the compressor member  126  of the turbocharger device  124 . In this case, fluid flowing through the bypass fluid system  142  is not cooled by the fluid cooler  133  for improved performance of the aftertreatment device  134 . 
         [0040]    Thus, the engine system  12 ,  112 , includes a bypass fluid system  42 ,  142  for supplying air to the aftertreatment device  34 ,  134 . It will be appreciated that the bypass fluid system  42 ,  142  supplies air to the aftertreatment device  34 ,  134  without the need of an independent air supply system or an air supply system that is driven by the engine  14 ,  114 . Thus, the engine system  112  can be less complex, can include less components, can be easier to integrate into the vehicle  10 ,  110 , and can improve efficiency as compared to prior art engine systems. 
         [0041]    Furthermore, the foregoing discussion discloses and describes merely exemplary embodiments of the present disclosure. One skilled in the art will readily recognize from such discussion, and from the accompanying drawings and claims, that various changes, modifications and variations may be made therein without departing from the spirit and scope of the disclosure as defined in the following claims.