Abstract: An engine system includes an engine having first and second exhaust manifolds each having outlet ports and a bypass runner. A first turbocharger is in fluid communication with the outlet port of the first manifold, and a second turbocharger in fluid communication with the outlet port of the second manifold. An exhaust aftertreatment device is in fluid communication with the first and second turbochargers. A turbocharger bypass circuit includes a valve assembly having an inlet side connected in fluid communication with the bypass runners of the first and second manifolds, an outlet side in fluid communication with the aftertreatment device, and a valve having an open position in which the inlet and outlet sides are in fluid communication and a closed position in which the inlet and outlet sides are not in fluid communication.

Abstract: An engine system includes an engine having first and second exhaust manifolds each having outlet ports and a bypass runner. A first turbocharger is in fluid communication with the outlet port of the first manifold, and a second turbocharger in fluid communication with the outlet port of the second manifold. An exhaust aftertreatment device is in fluid communication with the first and second turbochargers. A turbocharger bypass circuit includes a valve assembly having an inlet side connected in fluid communication with the bypass runners of the first and second manifolds, an outlet side in fluid communication with the aftertreatment device, and a valve having an open position in which the inlet and outlet sides are in fluid communication and a closed position in which the inlet and outlet sides are not in fluid communication.

Abstract: Methods and systems are provided for exhaust heat recovery and EGR cooling via a single heat exchanger. In one example, a method may include selecting a specific mode of operation of an engine exhaust system with the heat exchanger based on engine operating conditions and an estimated fuel efficacy factor. The fuel efficiency factor may take into account fuel efficacy benefits from EGR and exhaust heat recovery.

Abstract: Systems and methods are provided for an engine system having a split exhaust system. In one example, a system may include an engine having a plurality of cylinders, each of the plurality of cylinders including first and second exhaust ports, the first and second exhaust ports arranged in a non-alternating pattern across the plurality of cylinders and along a cylinder head, a blowdown exhaust manifold coupled to the first exhaust ports and an exhaust passage, and a scavenge exhaust manifold coupled to the second exhaust ports and an intake passage of the engine. In this way, the first and second exhaust ports may be arranged to enhance turbocharger performance characteristics.

Abstract: Systems and methods are provided for an engine system having a split exhaust system. In one example, a system may include an engine having a plurality of cylinders, each of the plurality of cylinders including first and second exhaust ports, the first and second exhaust ports arranged in a non-alternating pattern across the plurality of cylinders and along a cylinder head, a blowdown exhaust manifold coupled to the first exhaust ports and an exhaust passage, and a scavenge exhaust manifold coupled to the second exhaust ports and an intake passage of the engine. In this way, the first and second exhaust ports may be arranged to enhance turbocharger performance characteristics.

Abstract: Methods and systems are provided for improving surge control in a boosted engine system configured with an electric motor to provide electrical boost assistance. Tip-in and tip-out surge are addressed by increasing the opening of a compressor recirculation valve and coordinating the recirculation valve opening with adjustments to an exhaust waste-gate position and a power output by the electric motor. The adjustments enable an intake airflow to be provided that operates the compressor outside a surge region while providing a target boost pressure as operator torque demand increases or decreases.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, one or more valves of a set of first exhaust valves coupled to the second exhaust manifold may be deactivated in response to select engine operating conditions, while maintaining active all valves of a set of second exhaust valves coupled to the first exhaust manifold. The select engine operating conditions may include one or more of a deceleration fuel shut-off condition, a part throttle condition, and a cold start condition.

Abstract: Methods and systems are provided for warming an engine and/or engine fluids. In one example, a method may comprise powering on an electric motor of an intake boost device to generate heat, circulating coolant and/or engine oil through the boost device to absorb the heat produced by the boost device, and then flowing the coolant and/or engine oil to the engine to transfer the heat absorbed from the boost device to the engine. In this way, an engine may be warmed without running the engine rich by using the heat generated by the electric motor of the boost device to warm the engine.

Abstract: Methods and systems are provided for exhaust heat recovery and EGR cooling via a single heat exchanger. In one example, a method may include selecting a specific mode of operation of an engine exhaust system with the heat exchanger based on engine operating conditions and an estimated fuel efficacy factor. The fuel efficiency factor may take into account fuel efficacy benefits from EGR and exhaust heat recovery.

Abstract: Methods and systems are provided for improving surge control in a boosted engine system configured with an electric motor to provide electrical boost assistance. Tip-in and tip-out surge are addressed by increasing the opening of a compressor recirculation valve and coordinating the recirculation valve opening with adjustments to an exhaust waste-gate position and a power output by the electric motor. The adjustments enable an intake airflow to be provided that operates the compressor outside a surge region while providing a target boost pressure as operator torque demand increases or decreases.

Abstract: Methods and systems are provided for exhaust heat recovery and EGR cooling via a single heat exchanger. In one example, a method may include selecting a specific mode of operation of an engine exhaust system with the heat exchanger based on engine operating conditions and an estimated fuel efficacy factor. The fuel efficiency factor may take into account fuel efficacy benefits from EGR and exhaust heat recovery.

Abstract: Methods and systems are provided for warming an engine and/or engine fluids. In one example, a method may comprise powering on an electric motor of an intake boost device to generate heat, circulating coolant and/or engine oil through the boost device to absorb the heat produced by the boost device, and then flowing the coolant and/or engine oil to the engine to transfer the heat absorbed from the boost device to the engine. In this way, an engine may be warmed without running the engine rich by using the heat generated by the electric motor of the boost device to warm the engine.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, one or more valves of a set of first exhaust valves coupled to the second exhaust manifold may be deactivated in response to select engine operating conditions, while maintaining active all valves of a set of second exhaust valves coupled to the first exhaust manifold. The select engine operating conditions may include one or more of a deceleration fuel shut-off condition, a part throttle condition, and a cold start condition.

Abstract: Methods and systems are provided for controlling transitions between engine operating modes in a four-cylinder engine. One method includes transitioning engine operation between two-cylinder, three-cylinder, and four-cylinder modes wherein the transitioning includes a sequence of firing events such that successive firing events are separated by at least 120 crank angle degree intervals.

Abstract: Systems and methods for operating a driveline of a hybrid vehicle are disclosed. In one example, an engine may enter or stay in one of two cylinder modes in response to a request to a negative torque capacity of an electric machine being insufficient to provide a desired driveline braking torque. One cylinder mode operates cylinders with cylinder valves held closed and without fuel being injected to the cylinders while the other cylinder mode operates cylinders with valves that open and close without fuel being injected to the cylinders.

Abstract: Methods and systems are provided for operating a split exhaust engine system that provides blowthrough air and exhaust gas recirculation to an intake passage via a first exhaust manifold and exhaust gas to an exhaust passage via a second exhaust manifold. In one example, one or more valves of a set of first exhaust valves coupled to the second exhaust manifold may be deactivated in response to select engine operating conditions, while maintaining active all valves of a set of second exhaust valves coupled to the first exhaust manifold. The select engine operating conditions may include one or more of a deceleration fuel shut-off condition, a part throttle condition, and a cold start condition.

Abstract: Systems and methods for operating an engine with deactivating valves are presented. In one example, a groove in a camshaft controls oil flow to a valve operator that selectively activates and deactivates a poppet valve of a cylinder. The groove moves with the camshaft so that oil delivery to the valve operator is timed properly to deactivate and reactivate the cylinder.

Abstract: Methods and systems are provided for a wastegate of a turbocharger including a valve plate, valve actuation mechanism, and a bifurcated wastegate passage. In one example design, the wastegate may include a valve plate having an interior with a multiplane curved surface and a first mating feature centered along the curved surface, the curved surface forming a raised edge and a side opening on opposite sides of the valve plate; and a passage bifurcated by a central wall, an end of the central wall including a second mating feature adapted to have face-sharing contact with the first mating feature. The first mating feature may be either a rib or recessed slot formed on the valve plate, and the second mating feature may be one end of the central wall.

Abstract: An engine system is provided. The engine system may include an exhaust gas heat exchanger valve including an actuatable valve plate, a valve actuation assembly adjusting the position of the valve plate through operation of mechanical linkage coupled to the valve plate, and a flow reversal valve positioned in a coolant passage, the flow reversal valve configured to reverse the coolant flow in a flapper coolant conduit to trigger actuation of the mechanical linkage.

Abstract: An engine system is provided. The engine system may include an exhaust gas heat exchanger valve including an actuatable valve plate, a valve actuation assembly adjusting the position of the valve plate through operation of mechanical linkage coupled to the valve plate, and a flow reversal valve positioned in a coolant passage, the flow reversal valve configured to reverse the coolant flow in a flapper coolant conduit to trigger actuation of the mechanical linkage.