Abstract: A piston for balancing combustion efficiency and smoke generation with NOx production includes a combustion face forming a combustion bowl having a compound curvature increased in sharpness in a radially outward direction. An outer bowl surface defines a large radius of curvature adjacent an inner bowl surface, and a medium radius of curvature adjacent a cylindrical wall surface. The inner bowl, outer bowl, and wall surfaces together contour the combustion bowl, such that a diameter of the combustion bowl is about 124 mm so as to establish a bowl to bore ratio of about 0.71 in a direct injection compression ignition engine with a compression ratio of about 15:1 to 17:1.

Abstract: A piston for balancing combustion efficiency and smoke generation with NOx production includes a combustion face forming a combustion bowl having a compound curvature increased in sharpness in a radially outward direction. An outer bowl surface defines a large radius of curvature adjacent an inner bowl surface, and a medium radius of curvature adjacent a cylindrical wall surface. The inner bowl, outer bowl, and wall surfaces together contour the combustion bowl, such that a diameter of the combustion bowl is about 124 mm so as to establish a bowl to bore ratio of about 0.71 in a direct injection compression ignition engine with a compression ratio of about 15:1 to 17:1.

Abstract: The piston has a crown forming a piston bowl. The piston bowl has a center portion with a convex spherical shape, a floor having a convex frusto-conical shape adjacent the center portion, and a base having a concave toroidal shape surrounding the floor. The piston bowl also has a cylindrical wall extending tangentially from the base that surrounds the center portion. The piston has a top surface perpendicular to the cylindrical wall along a rim of the piston bowl. A ratio between the piston bowl depth and the cylindrical wall length is less than 4, and a ratio between the piston bowl diameter and the piston bowl depth is 4.7.

Abstract: The piston has a crown forming a piston bowl. The piston bowl has a center portion with a convex spherical shape, a floor having a convex frusto-conical shape adjacent the center portion, and a base having a concave toroidal shape surrounding the floor. The piston bowl also has a cylindrical wall extending tangentially from the base that surrounds the center portion. The piston has a top surface perpendicular to the cylindrical wall along a rim of the piston bowl. A ratio between the piston bowl depth and the cylindrical wall length is less than 4, and a ratio between the piston bowl diameter and the piston bowl depth is 4.7.

Abstract: A method of operating an internal combustion engine includes operating the engine in a first combustion mode. The method also includes switching operation of the engine to a second combustion mode. The method includes directing an exhaust stream of the engine into contact with a NOx adsorber substantially only during the operation in the second combustion mode.

Abstract: A method of operating an internal combustion engine including at least one cylinder and a piston slidable in the cylinder is provided. In at least one embodiment, the method includes: supplying a mixture of pressurized air and recirculated exhaust gas from an intake manifold to an air intake port of a combustion chamber in the cylinder; operating an air intake valve to open the air intake port to allow the pressurized air and exhaust gas mixture to flow between the combustion chamber and the intake manifold during a portion of a compression stroke of the piston; and operably controlling a fuel supply system to inject fuel into the combustion chamber via a common rail fuel injector.

Abstract: An engine and a method of operating an internal combustion engine is provided. The method comprises supplying a pressurized air from an intake manifold to an air intake port of a combustion chamber in the cylinder, operating an air intake valve to open the air intake port to allow the pressurized air and exhaust gas mixture to flow between the combustion chamber and the intake manifold during a portion of a compression stroke of the piston, and operating the engine in an HCCI combustion mode. In at least some embodiments, a mixture of pressurized air and recirculated exhaust gas is supplied from an intake manifold to an air intake port of a combustion chamber in the cylinder. In some embodiments, the method further comprises causing an exhaust stream of an engine to contact a NOx adsorber.

Abstract: Engines and methods of controlling an engine may involve at least one fluid actuators associated with one or more engine intake and/or exhaust valves. Timing of valve closing/opening and use of an air supply system may enable engine operation according to a Miller cycle.

Abstract: An engine and method of operating an internal combustion engine with either a continuously variable speed transmission or electric drive is provided. The engine and method comprises operating the engine at its optimum engine speed throughout a range of vehicle speeds through, supplying pressurized air from an intake manifold to an air intake port of a combustion chamber in the cylinder, and operating an air intake valve to open the air intake port to allow the pressurized air to flow between the combustion chamber and the intake manifold during a portion of a compression stroke of the piston. In at least one embodiment, the engine and method further comprises using a mixture of pressurized air and recirculated exhaust gas.

Abstract: An engine and method of operating an internal combustion engine is provided. The method comprises supplying pressurized air from an intake manifold to an air intake port of a combustion chamber in the cylinder, operating an air intake valve to open the air intake port to allow the pressurized air to flow between the combustion chamber and the intake manifold during a portion of a compression stroke of the piston, and filtering particulate matter from an exhaust stream of the engine with a particulate filter.

Abstract: A method and apparatus for operating a compression ignition engine having a cylinder wall, a piston, and a head defining a combustion chamber. The method and apparatus includes delivering fuel substantially uniformly into the combustion chamber, the fuel being dispersed throughout the combustion chamber and spaced from the cylinder wall, delivering an oxidant into the combustion chamber sufficient to support combustion at a first predetermined combustion duration, and delivering a diluent into the combustion chamber sufficient to change the first predetermined combustion duration to a second predetermined combustion duration different from the first predetermined combustion duration.

Abstract: A compound turbocharger is provided, including at least one housing. A first turbocharger having an outer shaft is disposed within the housing, and a second turbocharger is provided having an inner shaft co-axial with and extending within the outer shaft. At least one displacement limiter is disposed at a selected position along the length of the outer shaft. A method of reducing vibrational amplitude in an inner shaft of a coaxial shaft assembly is further provided, including the step of operably positioning at least one displacement limiter at a selected position along a length of the outer shaft.

Abstract: A method of operating an internal combustion engine includes operating the engine in a first combustion mode. The method also includes switching operation of the engine to a second combustion mode. The method includes directing an exhaust stream of the engine into contact with a NOx adsorber substantially only during the operation in the second combustion mode.

Abstract: An engine and method of operating an internal combustion engine with either a continuously variable speed transmission or electric drive is provided. The engine and method comprises operating the engine at its optimum engine speed throughout a range of vehicle speeds through, supplying pressurized air from an intake manifold to an air intake port of a combustion chamber in the cylinder, and operating an air intake valve to open the air intake port to allow the pressurized air to flow between the combustion chamber and the intake manifold during a portion of a compression stroke of the piston. In at least one embodiment, the engine and method further comprises using a mixture of pressurized air and recirculated exhaust gas.

Abstract: Engines and methods of controlling an engine may involve one or more fluidically controlled actuators associated with engine intake and/or exhaust valves. In some examples, the actuators may be used to hold valves open. Timing of valve closing/opening and possible use of an air supply system may enable engine operation according to a Miller cycle.

Abstract: Engines and methods of controlling an engine may involve one or more cams associated with engine intake and/or exhaust valves. In some examples, shifting the rotational phase of one or more cams advances and/or delays timing of the opening and/or closing of valves. Timing of valve closing/opening and possible use of an air supply system may enable engine operation according to a Miller cycle.

Abstract: An internal combustion engine has an engine block defining at least one cylinder, a head, a piston, an air intake valve, and a valve actuator. The valve actuator has an actuator housing defining a tank and a bore, and a piston adapted to engages the air intake valve. The valve actuator further has a control valve disposed between the tank and the bore in the actuator housing. The control valve selectively moves between a first position where fluid is allowed to flow between the tank and the bore and a second position where the fluid is prevented from flowing to trap fluid in the bore, thereby preventing the engine valve from returning to a closed position. The internal combustion engine also has at least one turbocharger fluidly connected to the air intake port, and a fuel supply system operable to controllably inject fuel into the combustion chamber.

Abstract: An engine and method of operating an internal combustion engine is provided. The method comprises supplying pressurized air from an intake manifold to an air intake port of a combustion chamber in the cylinder, operating an air intake valve to open the air intake port to allow the pressurized air to flow between the combustion chamber and the intake manifold during a portion of a compression stroke of the piston, and filtering particulate matter from an exhaust stream of the engine with a particulate filter.

Abstract: In one aspect, the present disclosure is directed to an internal combustion engine having an engine block defining at least one cylinder and a head connected with said engine block. The head has an air intake port and an exhaust port. The internal combustion engine also has a piston and a combustion chamber. The internal combustion engine further has an air intake valve movable to open and close the air intake port and an air supply system having at least one turbocharger fluidly connected to the air intake port. The internal combustion engine additionally has a fuel supply system operable to inject fuel into the combustion chamber, a cam assembly selectively mechanically linked to the air intake valve to move the air intake valve, and an electromagnetic actuator configured to decouple the cam assembly from the air intake valve and control movement of the air intake valve.

Abstract: Engines and methods of controlling an engine may involve at least one fluid actuators associated with one or more engine intake and/or exhaust valves. Timing of valve closing/opening and use of an air supply system may enable engine operation according to a Miller cycle.