Apparatuses, systems and method for utilizing multi-zoned combustion chambers (and/or multiple combustion chambers) for achieving compression ignition (and/or spark-assisted or fuel-assisted compression ignition) in an internal combustion engine are provided. In addition, improved apparatuses, systems and methods for achieving and/or controlling compression ignition (and/or spark-assisted or fuel-assisted compression ignition) in a Siamese cylinder internal combustion engine are provided.

A variable compression ratio engine includes an extra chamber formed at a cylinder head, an extra valve being able to open/close the extra chamber, and an actuator being able to open/close the extra chamber by driving the extra valve.

An internal combustion engine includes low and high pressure turbochargers connected in series. An engine cylinder has an intake valve that fluidly connects a main chamber of the engine cylinder with an outlet of the high pressure compressor through an intake passage. An exhaust gas recirculation passage is fluidly interconnected between exhaust and intake conduits. A pre-chamber encloses a spark plug and is fluidly open with the main chamber of the engine cylinder. A first fluid path extends from the intake passage directly to the pre-chamber, and a second fluid path extends from the intermediate passage directly to the pre-chamber.

The present disclosure relates to an engine in which compression and expansion is performed in the same cylinder. Also disclosed is a microprocessor for controlling the state of various valves in the cylinderincluding an intake valve, a transfer valve, and an exhaust valveto cause a compression or expansion to occur. A compression tank is provided for receiving, via the transfer valve, compressed air, which may be retrieved during an expansion (combustion) cycle. Compressed air for from multiple consecutive compressions may be stored in the tank and retrieved later, including for multiple consecutive expansions. Compression and expansion are not required to occur in any fixed or predetermined pattern and the microprocessor may evaluate vehicle sensors to determine a power demand, and cause compression or expansion to occur depending on the given power demand.

One embodiment is a system comprising an engine including a dedicated EGR cylinder configured to provide EGR to the engine via an EGR loop, a non-dedicated cylinder, a plurality of injectors, an ignition system including a plurality of spark plugs, an intake throttle, and an electronic control system. The electronic control system is configured to control combustion during transient operation of the engine by determining one or more combustion control parameters compensating for variation of one or more of inert matter, unburned air and unburned fuel in EGR output by the dedicated EGR cylinder during transient operation of the engine, and an effect of the EGR loop on inert matter, unburned air and unburned fuel provided to the plurality of cylinders, and controlling operation of at least one of the throttle, the ignition system and the plurality of injectors in response to at least one of the one or more combustion control parameters.

Embodiments disclosed herein relate to internal combustion engines, combustion systems that include such internal combustion engines, and controls for controlling operation of the combustion engine. The internal combustion engine may include one or more mechanisms for injecting fuel, air, fuel-air mixture, or combinations thereof directly into one or more cylinders, and controls may operate or direct operation of such mechanisms.

Methods and systems for operating an engine and determining relative compression ratio differences from a reference cylinder are disclosed. In one example, an engine is rotated via a starter or another type of electric machine and engine deceleration rates related to each engine cylinder are determined. The engine deceleration rates form a basis for compression ratio factors for each engine cylinder.

Methods and systems are provided for reducing engine compression torque when an engine having a split exhaust system is spun unfueled. In one example, a method may include maintaining closed a blowdown exhaust valve of a cylinder, the blowdown exhaust valve coupled to a first exhaust manifold that directs gases from the cylinder to a catalyst, and opening a scavenge exhaust valve of the cylinder, the scavenge exhaust valve coupled to a second exhaust manifold that directs gases from the cylinder to an exhaust gas recirculation system. In this way, compression of gases within they cylinder is reduced while gas flow to the catalyst is prevented.

A method for operating a reciprocating internal combustion engine in an engine braking mode of operation is provided. The method includes closing, for a first time, at least one exhaust valve of at least one cylinder in the engine braking mode of operation within a working cycle, and opening for a first time, and closing, for a second time, the at least one exhaust valve of the at least one cylinder, and opening for a second time to thereby discharge compressed gas in the cylinder via a piston of the cylinder from the cylinder. After the first opening and before the second closing, the exhaust valve is kept open, until the cylinder is filled with gas which flows through at least one exhaust channel from at least one second cylinder of the reciprocating internal combustion engine.

A control device for an internal combustion engine that includes an external EGR device having an EGR passage and an EGR valve installed at an end portion of the EGR passage on the side of a cylinder is configured, when a high intake air pressure condition is met and there is no EGR gas introduction request, to execute an EGR cut control using a variable valve operating device. In the EGR cut control, the control device is configured to open an intake valve during the intake stroke after the EGR valve opens, and adjust an overlap area such that an outflow gas amount via the EGR valve becomes equal to an inflow gas amount via the EGR valve. The EGR passage is configured so as to store a gas that flows out to the EGR passage from the cylinder via the EGR valve during of the EGR cut control.