Abstract:
A torque adaptation system is provided. The system includes: a torque error estimator module that estimates a torque error based on an error propagation model and a plurality of torque model parameters; and an adapt torque module that adapts a model torque based on the torque error.

Description:
TECHNICAL FIELD 
       [0001]    The present invention relates to an intake manifold assembly for an internal combustion engine having a cross-plane crankshaft. 
       BACKGROUND OF THE INVENTION 
       [0002]    Internal combustion engines with eight cylinders arranged in a V-type configuration (two banks of four cylinders disposed at a generally ninety degree angle to each other) typically include a dual plane or cross-plane crankshaft. With a cross-plane crankshaft, each crank pin (of four) is positioned at a ninety degree angle from the previous, such that when viewed from one end of the crankshaft, along the longitudinal axis, that the crank pins form a cross shape. With a cross-plane crankshaft, a cylinder of the first bank of cylinders shares a crank pin with a cylinder of the second bank of cylinders. The cross-plane crankshaft can achieve very good engine balance as a result of counterweights formed integrally with the crankshaft. While the sequential firing of the cylinders is regular overall, the firing of each bank is not. Within the sequential firing order, two cylinders on each bank of cylinders will fire ninety crank angle degrees apart from one another, whereas all other cylinders on a respective bank fire at 180 crank angle degrees intervals. 
         [0003]    With a boosted diesel engine, such as a turbo charged or supercharged engine, the second close firing cylinder of each bank tends to induct more intake air than the first close firing cylinder resulting in a greater amount of intake air trapped within the second close firing cylinder. As a result, at high intake air flow rates, the second close firing cylinder of each bank of cylinders will have comparatively higher peak in-cylinder pressures that may limit power output due to engine stress/fatigue constraints. Additionally, the remaining six cylinders, with comparatively low peak in-cylinder pressures, may operate below their power potential. 
       SUMMARY OF THE INVENTION 
       [0004]    An intake assembly is provided for a sequentially fired eight cylinder V-type internal combustion engine including a cylinder block having a first bank of cylinders and a second bank of cylinders wherein the first bank of cylinders defines the first, third, fifth, and seventh cylinder positioned from a first end to a second end of the engine. The second bank of cylinders defines the second, fourth, sixth, and eighth cylinder positioned from the first end to the second end of the engine. The intake assembly includes first and second intake plenums mounted with respect to the engine. Each of the first and second intake plenums are operable to communicate intake air to at least one of the first, third, fifth, and seventh cylinders. Additionally, third and fourth intake plenums are mounted with respect to the engine. Each of the third and fourth intake plenums are operable to communicate the intake air to at least one of the second, fourth, sixth, and eighth cylinders. The first bank of cylinders includes a first group of two cylinders that fire ninety crank angle degrees apart from each. The second bank of cylinders includes a second group of two cylinders that fire ninety crank angle degrees apart from each other. The first intake plenum is operable to communicate the intake air to one cylinder of the first group of two cylinders and the second intake plenum is operable to communicate the intake air to another cylinder of the first group of two cylinders. The third intake plenum is operable to communicate the intake air to one cylinder of the second group of two cylinders and the fourth intake plenum is operable to communicate the intake air to another cylinder of the second group of two cylinders. 
         [0005]    The first, second, third, and fourth intake plenums may be mounted with respect to the engine in an outboard configuration. The intake assembly may further include an intake air duct and a first and second flow passage in downstream fluid communication with the intake air duct. First and second runner passages may be provided in downstream fluid communication with the first flow passage. The first and second runner passages may be provided in fluid communication with a respective one of the first and second intake plenums. Third and fourth runner passages may be provided in downstream fluid communication with the second flow passage. The third and fourth runner passages may be provided in fluid communication with a respective one of the third and fourth intake plenums. A compressor may be provided to pressurize the intake air. An internal combustion engine incorporating the disclosed intake assembly is also provided. 
         [0006]    The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0007]      FIG. 1  is a schematic plan view of an eight cylinder, V-type internal combustion engine having a sequential firing order of  1 - 2 - 7 - 8 - 4 - 5 - 6 - 3  and illustrating an intake manifold assembly consistent with the present invention; 
           [0008]      FIG. 2  is a schematic plan view of an eight cylinder, V-type internal combustion engine have a sequential firing order of  1 - 5 - 6 - 3 - 4 - 2 - 7 - 8  and illustrating an alternate embodiment of the intake manifold assembly of the present invention; 
           [0009]      FIG. 3  is a schematic plan view of an eight cylinder, V-type internal combustion engine have a sequential firing order of  1 - 2 - 7 - 3 - 4 - 5 - 6 - 8  and illustrating an alternate embodiment of the intake manifold assembly of the present invention; 
           [0010]      FIG. 4  is a schematic plan view of an eight cylinder, V-type internal combustion engine have a sequential firing order of  1 - 2 - 6 - 3 - 4 - 5 - 7 - 8  and illustrating an alternate embodiment of the intake manifold assembly of the present invention; 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0011]    Referring to the drawings wherein like reference numbers correspond to like or similar components throughout the several figures, there is shown in  FIG. 1  an internal combustion engine  10 . The internal combustion engine  10  may be either a spark-ignited type or a compression-ignited type. For discussion hereinbelow, it will be assumed that the internal combustion engine  10  is a compression-ignited internal combustion engine. The internal combustion engine  10  includes a cylinder case or block  12  having a first bank of cylinders  14  and a second bank of cylinders  16 . The first and second bank of cylinders  14  and  16  are arranged in a generally V-shaped configuration such that the internal combustion engine  10  may be characterized as a V-type internal combustion engine. The space at least partially defined by the included angle of the first and second bank of cylinders  14  and  16  is generally referred to as a valley  18 . 
         [0012]    Each of the first and second bank of cylinders  14  and  16  define a plurality of cylinders  20 . Each of the cylinders  20  defined by the first bank of cylinders  14  are arranged from a first end of the internal combustion engine  10  to a second end of the internal combustion engine  10  as first cylinder  1 , third cylinder  3 , fifth cylinder  5 , and seventh cylinder  7 . Similarly, each of the cylinders  20  defined by the second bank of cylinders  16  are arranged from the first end of the internal combustion engine  10  to the second end of the internal combustion engine  10  as second cylinder  2 , fourth cylinder  4 , sixth cylinder  6 , and eighth cylinder  8 . As such, the internal combustion engine  10  may be further characterized by having eight cylinders  20 . 
         [0013]    The internal combustion engine may further include an intake manifold assembly  22 . The intake manifold assembly is operable to provide intake air  24  to the cylinders  20  of the internal combustion engine  10  to enable combustion of fuel, not shown, within the cylinders  20 . The intake manifold assembly  22  includes an intake air duct  26  in fluid communication with a first flow passage and a second flow passage  28  and  30 , respectively. The first flow passage  28  is in fluid communication with a first plenum runner  32  and a second plenum runner  34 . The first plenum runner  32  is operable to communicate intake air  24  to a first plenum  36  for subsequent introduction to at least one of the first cylinder  1 , third cylinder  3 , fifth cylinder  5 , and seventh cylinder  7 . The second plenum runner  34  is operable to communicate intake air  24  to a second plenum  38  for subsequent introduction to the at least one of the first cylinder  1 , third cylinder  3 , fifth cylinder  5 , and seventh cylinder  7  that is not in fluid communication with the first intake plenum  36 . 
         [0014]    The second flow passage  30  is in fluid communication with a third plenum runner  40  and a fourth plenum runner  42 . The third plenum runner  40  is operable to communicate intake air  24  to a third plenum  44  for subsequent introduction to at least one of the second cylinder  2 , fourth cylinder  4 , sixth cylinder  6 , and eighth cylinder  8 . The fourth plenum runner  42  is operable to communicate intake air  24  to a fourth plenum  46  for subsequent introduction to the at least one of the second cylinder  2 , fourth cylinder  4 , sixth cylinder  6 , and eighth cylinder  8  that is not in fluid communication with the third intake plenum  44 . 
         [0015]    As illustrated in  FIG. 1 , the first and second intake plenum  36 , and  38  are mounted in an outboard position with respect to the internal combustion engine  10 . That is, the first and second intake plenum  36  and  38  are disposed substantially adjacent to the first bank of cylinders  14  opposite the valley  18 . Similarly, the third and fourth intake plenum  44  and  46  are mounted in an outboard position with respect to the internal combustion engine  10 . That is, the third and fourth intake plenum  44  and  46  are disposed substantially adjacent to the second bank of cylinders  16  opposite the valley  18 . A compressor  48 , such as a turbocharger or a supercharger, may be provided in fluid communication with the intake manifold assembly  22 , and operate to selectively pressurize the intake air  24  within the intake manifold assembly  22 . 
         [0016]    The intake manifold assembly  22  as shown in  FIG. 1  is configured for a sequential cylinder firing sequence of the first cylinder  1 , second cylinder  2 , seventh cylinder  7 , eighth cylinder  8 , fourth cylinder  4 , fifth cylinder  5 , sixth cylinder  6 , and third cylinder  3 , or what is commonly referred to as a  1 - 2 - 7 - 8 - 4 - 5 - 6 - 3  firing order. With this configuration, the close firing pair of cylinders  20  on the first bank of cylinders  14  are the third cylinder  3  and the first cylinder  1 . The first intake plenum  36  is configured to communicate intake air  24  to the first cylinder  1 , and the second intake plenum  38  is configured to communicate intake air to the third cylinder  3 , fifth cylinder  5 , and seventh cylinder  7 . The close firing pair of cylinders  20  on the second bank of cylinders  16  are the eighth cylinder  8  and the fourth cylinder  4 . The third intake plenum  44  is configured to communicate intake air  24  to the second cylinder  2  and fourth cylinder  4 , and the fourth intake plenum  46  is configured to communicate intake air to the sixth cylinder  6  and eighth cylinder  8 . By configuring the intake manifold assembly  22  in this way, the tuning effects of the close firing pair of cylinders  20  on each of the first and second bank of cylinders  14  and  16  may be substantially attenuated. 
         [0017]    Referring now to  FIG. 2  there is shown the internal combustion engine  10  having an alternate embodiment of the intake manifold assembly  22 , shown in  FIG. 1 , and generally indicated as  22 A. The intake manifold assembly  22 A is configured for a sequential cylinder firing sequence of the first cylinder  1 , fifth cylinder  5 , sixth cylinder  6 , third cylinder  3 , fourth cylinder  4 , second cylinder  2 , seventh cylinder  7 , eighth cylinder  8 , or what is commonly referred to as a  1 - 5 - 6 - 3 - 4 - 2 - 7 - 8  firing order. With this configuration, the close firing pair of cylinders  20  on the first bank of cylinders  14  are the first cylinder  1  and the fifth cylinder  5 . The first intake plenum  36  is configured to communicate intake air  24  to the first cylinder  1 , and the third cylinder  3 , and the second intake plenum  38  is configured to communicate intake air  24  to the fifth cylinder  5  and seventh cylinder  7 . The close firing pair of cylinders  20  on the second bank of cylinders  16  are the fourth cylinder  4  and the second cylinder  2 . The third intake plenum  44  is configured to communicate intake air  24  to the second cylinder  2 , and the fourth intake plenum  46  is configured to communicate intake air  24  to the fourth cylinder  4 , sixth cylinder  6 , and eighth cylinder  8 . By configuring the intake manifold assembly  22 A in this way, the tuning effects of the close firing pair of cylinders  20  on each of the first and second bank of cylinders  14  and  16  may be substantially attenuated. 
         [0018]    Referring now to  FIG. 3  there is shown the internal combustion engine  10  having an alternate embodiment of the intake manifold assembly  22 , shown in  FIG. 1 , and generally indicated as  22 B. The intake manifold assembly  22 B is configured for a sequential cylinder firing sequence of the first cylinder  1 , second cylinder  2 , seventh cylinder  7 , third cylinder  3 , fourth cylinder  4 , fifth cylinder  5 , sixth cylinder  6 , and eighth cylinder  8 , or what is commonly referred to as a  1 - 2 - 7 - 3 - 4 - 5 - 6 - 8  firing order. With this configuration, the close firing pair of cylinders  20  on the first bank of cylinders  14  are the seventh cylinder  7  and the third cylinder  3 . The first intake plenum  36  is configured to communicate intake air  24  to the first cylinder  1 , and the third cylinder  3 , and the second intake plenum  38  is configured to communicate intake air  24  to the fifth cylinder  5  and seventh cylinder  7 . The close firing pair of cylinders  20  on the second bank of cylinders  16  are the sixth cylinder  6  and the eight cylinder  8 . The third intake plenum  44  is configured to communicate intake air  24  to the fourth cylinder  4 , sixth cylinder  6 , and eighth cylinder  8 , and the fourth intake plenum  46  is configured to communicate intake air  24  to the second cylinder  2 . By configuring the intake manifold assembly  22 B in this way, the tuning effects of the close firing pair of cylinders  20  on each of the first and second bank of cylinders  14  and  16  may be substantially attenuated. 
         [0019]    Referring now to  FIG. 4  there is shown the internal combustion engine  10  having an alternate embodiment of the intake manifold assembly  22 , shown in  FIG. 1 , and generally indicated as  22 C. The intake manifold assembly  22 C is configured for a sequential cylinder firing sequence of the first cylinder  1 , second cylinder  2 , sixth cylinder  6 , third cylinder  3 , fourth cylinder  4 , fifth cylinder  5 , seventh cylinder  7 , and eight cylinder  8 , or what is commonly referred to as a  1 - 2 - 3 - 4 - 5 - 7 - 8  firing order. With this configuration, the close firing pair of cylinders  20  on the first bank of cylinders  14  are the fifth cylinder  5  and the seventh cylinder  7 . The first intake plenum  36  is configured to communicate intake air  24  to the first cylinder  1 , third cylinder  3 , and fifth cylinder  5 , and the second intake plenum  38  is configured to communicate intake air  24  to the seventh cylinder  7 . The close firing pair of cylinders  20  on the second bank of cylinders  16  are the second cylinder  2  and the sixth cylinder  6 . The third intake plenum  44  if configured to communicate intake air  24  to the second cylinder  2  and fourth cylinder  4 , and the fourth intake plenum  46  is configured to communicate intake air  24  to the sixth cylinder  6  and eighth cylinder  8 . By configuring the intake manifold assembly  22 C in this way, the tuning effects of the close firing pair of cylinders  20  on each of the first and second bank of cylinder  14  and  16  may be substantially attenuated. 
         [0020]    By effectively separating the flow path of intake air  24  to the close firing pair of cylinders  20  on each of the first and second banks of cylinders  14  and  16 , the cylinder-to-cylinder combustion variation of the internal combustion engine  10  may be substantially reduced. This reduction in variation may improve power density and exhaust emissions of the internal combustion engine  10 . 
         [0021]    While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims.