Abstract: An internal combustion engine is configured to operate in a homogeneous-charge compression-ignition combustion mode and a spark-ignition combustion mode employing late intake valve closing. A method for operating the internal combustion engine includes determining an amount of residual gas re-inducted into a combustion chamber from a previous engine cycle and determining an amount of fresh air trapped in the combustion chamber for the present engine cycle based upon the amount of residual gas re-inducted into the combustion chamber from the previous engine cycle. Engine fueling to the cylinder for the present engine cycle is controlled based upon the amount of fresh air trapped in the combustion chamber for the present engine cycle.

Abstract: The method can control a powertrain in order to maintain the charge temperature at a desired value regardless of exhaust manifold pressure or altitude. The method includes the following steps: (a) receiving a torque request; (b) determining a desired air charge based, a least in part, on the torque request; (c) determining an actual air charge based, at least in part, on input signals from a manifold absolute pressure (MAP) sensor and a mass airflow (MAF) sensor; (d) adjusting an intake valve timing of the intake valve such that the actual air charge is equal to a desired air charge, and (e) adjusting throttle position and actuator positions of boosting devices such that the actual intake manifold pressure is equal to the desired intake manifold pressure.

Abstract: An engine assembly includes an internal combustion engine with an engine block having at least one cylinder. An intake manifold and an exhaust manifold are each fluidly connected to the at least one cylinder and define an intake manifold pressure (pi) and an exhaust manifold pressure (pe), respectively. A controller is operatively connected to the internal combustion engine and configured to receive a torque request (TR). The controller is programmed to determine a desired fuel mass (mf) for controlling a torque output of the internal combustion engine. The desired fuel mass (mf) is based at least partially on the torque request (TR), the intake and exhaust manifold pressures and a pressure-volume (PV) diagram of the at least one cylinder.

Abstract: An engine assembly includes an internal combustion engine with an engine block having at least one cylinder and at least one piston moveable within the at least one cylinder. A crankshaft is moveable to define a plurality of crank angles (CA) from a bore axis defined by the cylinder to a crank axis defined by the crankshaft. A controller is operatively connected to the internal combustion engine and configured to receive a torque request (TR). The controller is programmed to determine a desired combustion phasing (CAd) for controlling a torque output of the internal combustion engine. The desired combustion phasing is based at least partially on the torque request (TR) and a pressure-volume (PV) diagram of the at least one cylinder.

Abstract: An internal combustion engine is configured to operate in a homogeneous-charge compression-ignition combustion mode. A method for operating the internal combustion engine includes determining a desired effective charge dilution for a cylinder charge for a cylinder firing event. A desired air/fuel ratio, a desired intake air mass and a desired intake oxygen are determined to achieve the desired effective charge dilution for a combustion event. The desired air/fuel ratio is adjusted based upon a difference between the desired intake oxygen and the actual intake oxygen, and engine operation is controlled to achieve the adjusted desired air/fuel ratio.

Abstract: Controlling combustion in a spark-ignition direction-injection internal combustion engine includes providing an initial injected fuel mass timing and an initial spark ignition timing. A combustion phasing error is monitored and compared with each of the initial injected fuel mass timing and the initial spark ignition timing. An adjusted injected fuel mass timing and an adjusted desired spark ignition timing is determined based on the comparing for maintaining a desired combustion phasing.

Abstract: An internal combustion engine operates in a homogeneous-charge compression-ignition combustion mode. A method for controlling the internal combustion engine in response to a fast transient event from a low-load state to a high-load state includes operating the engine with a negative valve overlap between an intake valve and an exhaust valve, and determining a preferred combustion phasing responsive to the high-load state. A preferred EGR mass and a preferred intake valve timing corresponding to the preferred combustion phasing are determined. A first intake valve timing is determined in response to a difference between the preferred EGR mass and an actual EGR mass. The intake valve timing is controlled in response to a difference between the preferred intake valve timing and the first intake valve timing.

Abstract: An internal combustion engine is configured to operate in a homogeneous-charge compression-ignition combustion mode. Operation of the engine includes determining a combustion pressure parameter for each cylinder. Fueling for each cylinder is controlled responsive to a target state for the combustion pressure parameter for the corresponding cylinder. An end-of-injection timing and a corresponding spark ignition timing for each cylinder are controlled responsive to a target mass-burn-fraction point for an engine operating point.

Abstract: An internal combustion engine is configured to operate in a homogeneous-charge compression-ignition combustion mode and a spark-ignition combustion mode employing late intake valve closing. A method for operating the internal combustion engine includes determining an amount of residual gas re-inducted into a combustion chamber from a previous engine cycle and determining an amount of fresh air trapped in the combustion chamber for the present engine cycle based upon the amount of residual gas re-inducted into the combustion chamber from the previous engine cycle. Engine fueling to the cylinder for the present engine cycle is controlled based upon the amount of fresh air trapped in the combustion chamber for the present engine cycle.

Abstract: The method can control a powertrain in order to maintain the charge temperature at a desired value regardless of exhaust manifold pressure or altitude. The method includes the following steps: (a) receiving a torque request; (b) determining a desired air charge based, a least in part, on the torque request; (c) determining an actual air charge based, at least in part, on input signals from a manifold absolute pressure (MAP) sensor and a mass airflow (MAF) sensor; (d) adjusting an intake valve timing of the intake valve such that the actual air charge is equal to a desired air charge, and (e) adjusting throttle position and actuator positions of boosting devices such that the actual intake manifold pressure is equal to the desired intake manifold pressure.

Abstract: A combustion mode transition control for controlling a transition between a homogeneous-charge compression-ignition (HCCI) combustion mode and a spark-ignition (SI) combustion mode includes slowly transitioning intake and exhaust camshafts from initial phase settings corresponding to one of the HCCI and SI combustion modes to target phase settings corresponding to the other of the HCCI and SI combustion modes. An ignition spark timing and an injected fuel mass are coordinated with the transitioning of the intake and exhaust camshaft phase settings to substantially maintain engine load continuity during the transitioning of the intake and exhaust camshaft phase settings.

Abstract: A method to control an internal combustion engine includes controlling the engine in a homogeneous charge compression ignition mode and depending upon the operating range of the engine operating both intake and exhaust valves with one of a high-lift profile or a low lift profile or the exhaust valves with a low-lift profile and the intake valves with a high-lift profile.

Abstract: A method can be used to determine the total residual gas volume in a cylinder when the piston of an internal combustion engine is at the bottom dead center (BDC) position. The method includes: (a) measuring an intake manifold pressure and an exhaust manifold pressure; (b) determining a residual gas volume in the at least one cylinder originating from a current engine cycle; (c) determining a residual gas volume in the at least one intake port originating from at least one previous engine cycle; and (d) determining a total residual gas volume when the piston is at a BDC position based, at least in part, on the residual gas volume in the at least one cylinder originating from the current engine cycle and the residual gas volume in the at least one cylinder originating from at least one previous engine cycle.

Abstract: An internal combustion engine is configured to operate in a homogeneous-charge compression-ignition combustion mode. A method for operating the internal combustion engine includes determining a desired effective charge dilution for a cylinder charge for a cylinder firing event. A desired air/fuel ratio, a desired intake air mass and a desired intake oxygen are determined to achieve the desired effective charge dilution for a combustion event. The desired air/fuel ratio is adjusted based upon a difference between the desired intake oxygen and the actual intake oxygen, and engine operation is controlled to achieve the adjusted desired air/fuel ratio.

Abstract: A method to control a non-linear system includes operating a learning cycle to approximate characteristics of the system and, once the learning cycle is complete, operating the system based upon the characteristics. The learning cycle includes monitoring operation of the system, approximating the characteristics of the system with a recursive least squares approximation based upon the monitored operation, comparing variance of the operation to a threshold variance, and completing the learning cycle based upon the variance exceeding the threshold variance.

Abstract: A piston for an internal combustion engine is located within a cylinder of the engine. The piston includes a dish-shaped depression in a surface of the piston exposed to a combustion chamber of the cylinder providing a recess from a nominal top of the piston. The depression includes a depression boundary located at the nominal top of the piston and proximate to an outer diameter of the piston, an apex, and inclined walls connecting the apex to the depression boundary.

Abstract: An internal combustion engine is configured to operate in a homogeneous-charge compression-ignition combustion mode. Operating the internal combustion engine includes determining an integrated thermal state parameter from an aggregation of engine environment factors. A feed-forward engine control scheme is executed to determine states for engine control parameters. The states for the engine control parameters correspond to a preferred combustion phasing responsive to an operator torque request and the integrated thermal state parameter. Operation of the internal combustion engine is controlled to achieve the preferred combustion phasing using the states for the engine control parameters.

Abstract: A direct injection engine includes a fuel injector receiving a flow of pressurized fuel. The fuel injector provides fuel injections directly into a combustion chamber of the engine. The fuel injector includes a first fuel injector nozzle opening directing with a first narrow injection angle a first portion of a fuel injection mass at a spark gap of a spark plug. The fuel injector further includes a second fuel injector nozzle opening dispersing with a second wider injection angle a second portion of the fuel injection mass within the combustion chamber.

Abstract: A direct-injection internal combustion engine includes an intake camshaft with a low-lift intake cam and a high-lift intake cam, a variable lift control for selectively operating an intake valve in one of a low-lift intake valve profile with the low-lift intake cam and a high-lift intake valve profile with the high-lift intake cam, a variable cam phase control operative on the intake camshaft for simultaneously controlling the phase of the low-lift intake cam and the high-lift intake cam, an ignition spark control, a fuel injection control, an exhaust gas recirculation control, and an intake throttle control.

Abstract: A method for controlling combustion in a multi-cylinder internal combustion engine operating in a controlled auto-ignition mode includes providing combustion control parameters, determining peak cylinder pressures and crank angle location of the peak cylinder pressures. Cylinder volumes at the peak cylinder pressures and at intake valve closings are determined and cylinder pressures at intake valve closings are determined. A combustion parameter for each cylinder is calculated based upon the peak cylinder pressure, the cylinder pressure at the intake valve closing, the crank angle location of the peak cylinder pressure, the cylinder volume coincident with the peak cylinder pressure, and the cylinder volume at the intake valve closing. A target combustion parameter is determined and the calculated combustion parameter for each cylinder is compared to the target combustion parameter.