Abstract: A combustion manager portion of an engine controller is responsive to ambient air density and engine temperature signals to schedule charge flow and EGR fraction commands. The combustion manager includes a data structure determination block operable to select an appropriate engine speed/engine fueling data structure based on air density and engine temperature information as well as on desired emissions level and engine operating state (i.e., steady state or transient) information. Charge flow and EGR fraction determination blocks are, in turn, responsive to current engine speed and engine fueling information to produce compute the EGR fraction and charge flow commands as a function of the selected engine speed/engine fueling data structures.

Abstract: A variable geometry turbine and active wastegate are provided in combination along with independent control of the variable geometry turbine and wastegate valve so as to independently control exhaust gas recirculation flow and air flow in an internal combustion engine. Such independent control of exhaust gas recirculation flow and air flow in an internal combustion engine is achieved by providing a system for exhaust gas recirculation including an intake air manifold, an exhaust manifold, an exhaust gas recirculation passage providing fluid communication between the exhaust manifold and the intake air manifold, a variable geometry turbine positioned downstream of the exhaust manifold, and a waste gate passage providing fluid communication between the exhaust gas manifold and a point downstream of the variable geometry turbine.

Abstract: A variable geometry turbine and active wastegate are provided in combination along with independent control of the variable geometry turbine and wastegate valve so as to independently control exhaust gas recirculation flow and air flow in an internal combustion engine. Such independent control of exhaust gas recirculation flow and air flow in an internal combustion engine is achieved by providing a system for exhaust gas recirculation including an intake air manifold, an exhaust manifold, an exhaust gas recirculation passage providing fluid communication between the exhaust manifold and the intake air manifold, a variable geometry turbine positioned downstream of the exhaust manifold, and a waste gate passage providing fluid communication between the exhaust gas manifold and a point downstream of the variable geometry turbine.