A two stage turbocharger for an internal combustion engine, the two stage turbocharger comprising a high pressure turbine fluidly connected to an exhaust manifold of the engine through a high pressure turbine inlet duct and a low pressure turbine fluidly connected to the high pressure turbine through a low pressure turbine inlet duct, wherein the low pressure turbine is a variable geometry turbine, wherein the two stage turbocharger comprise a bypass duct system to bypass the variable geometry low pressure turbine, wherein the bypass duct system comprises a bypass valve.

A ducted combustion system includes a combustion chamber and a fuel injector in fluid connection with the combustion chamber, which includes an orifice opening from an injector tip of the fuel injector, the orifice injecting fuel into the combustion chamber as a fuel jet, the fuel jet flowing, within the combustion chamber, in a fuel flow direction. The system includes at least one duct disposed within the combustion chamber, the at least one duct being disposed such that the fuel jet, at least partially, enters one of the at least one ducts upon being injected into the combustion chamber. The at least one duct may be configured for having a flow field air stream within the duct, prior to entrance of the fuel jet, the flow field air stream having a flow direction that is substantially similar to the fuel flow direction.

A ducted combustion system includes a combustion chamber and a fuel injector in fluid connection with the combustion chamber, which includes an orifice opening from an injector tip of the fuel injector, the orifice injecting fuel into the combustion chamber as a fuel jet, the fuel jet flowing, within the combustion chamber, in a fuel flow direction. The system includes at least one duct disposed within the combustion chamber, the at least one duct being disposed such that the fuel jet, at least partially, enters one of the at least one ducts upon being injected into the combustion chamber. The at least one duct may be configured for having a flow field air stream within the duct, prior to entrance of the fuel jet, the flow field air stream having a flow direction that is substantially similar to the fuel flow direction.

A duct structure for a fuel injector assembly of an engine includes a first ring structure, a plurality of ducts, a plurality of posts, and an engagement structure. The fuel injector assembly includes a fuel injector having a plurality of orifices to discharge fuel. The first ring structure is configured to be coupled to a cylinder head of the engine, and defines a central axis. The ducts are circularly arrayed around the central axis, and are configured to provide passages to the fuel discharged from the fuel injector. The posts connect the ducts to the first ring structure. Further, the engagement structure is configured to engage with the fuel injector to align the ducts with the orifices such that each of the plurality of ducts is configured to receive fuel discharged from a corresponding one of the plurality of orifices.

A duct structure for a fuel injector assembly of an engine includes a first ring structure, a plurality of ducts, a plurality of posts, and an engagement structure. The fuel injector assembly includes a fuel injector having a plurality of orifices to discharge fuel. The first ring structure is configured to be coupled to a cylinder head of the engine, and defines a central axis. The ducts are circularly arrayed around the central axis, and are configured to provide passages to the fuel discharged from the fuel injector. The posts connect the ducts to the first ring structure. Further, the engagement structure is configured to engage with the fuel injector to align the ducts with the orifices such that each of the plurality of ducts is configured to receive fuel discharged from a corresponding one of the plurality of orifices.

An internal combustion engine includes an engine block having a cylinder bore and a cylinder head having a flame deck surface disposed at one end of the cylinder bore. A piston connected to a rotatable crankshaft and configured to reciprocate within the cylinder bore has a piston crown portion facing the flame deck surface such that a combustion chamber is defined within the cylinder bore and between the piston crown and the flame deck surface. A fuel injector having a nozzle tip disposed in fluid communication with the combustion chamber has at least one nozzle opening configured to inject a fuel jet into the combustion chamber along a fuel jet centerline. At least one arcuate indent is formed in the top surface in aligned fashion with the fuel jet and including an entry surface, a recirculation surface and a wall.

An engine control system performs a first control in the first place at the time of acceleration. Then, when an actual supercharging pressure is increased to a specified supercharging pressure, the engine control system performs a second control. In this way, at the time of acceleration, a turbine capacity and a valve overlap amount of an intake valve and an exhaust valve of an engine are optimized in correspondence to a driving state of an engine, whereby the intake valve and the exhaust valve of the engine can be made to overlap each other on the condition that a scavenging effect is larger than the effect of an exhaust interference during a valve overlap period.

A piston system includes a piston housing having a cylindrical body and forming an opening; a piston head positioned within and slidingly engaged with the opening; a first conduit extending from a side of the piston head to a top surface of the piston head; a first pocket extending partially within the cylindrical body of the piston housing.

A piston system includes a piston housing having a cylindrical body and forming an opening; a piston head positioned within and slidingly engaged with the opening; a first conduit extending from a side of the piston head to a top surface of the piston head; a first pocket extending partially within the cylindrical body of the piston housing.

A system for an internal combustion engine can include a separation device and an engine component including first and second valves. The separation device can separate intake air into a volume of nitrogen-rich air and a volume of oxygen-rich air. A first valve element can be movable relative to a first valve body and can have an annular shape disposed about a central axis of the combustion chamber. The first valve body can be fluidly coupled to the separation device and direct the oxygen-rich air into a central area of the combustion chamber. A second valve element can be movable relative to a second valve body and can have an annular shape disposed about the central axis, radially outward of the first valve. The second valve body can be fluidly coupled to the separation device and can direct the nitrogen-rich air to a peripheral area of the combustion chamber.