A method for starting an internal combustion engine comprises the steps of: providing an internal combustion engine having at least one cylinder and a piston supported at a crankshaft for repeated reciprocal movement in the cylinder so as to define a main combustion chamber, the internal combustion engine further having an ignition device arranged in said cylinder with an igniter portion and a fuel injector which are both arranged at a pre-chamber, wherein the pre-chamber has a plurality of orifices for providing fluid communication between said pre-chamber and the main combustion chamber, injecting fuel in the pre-chamber, and igniting the injected fuel in the pre-chamber for pre-heating of the pre-chamber prior to injecting fuel in the main combustion chamber for combusting the injected fuel in the main combustion chamber.

Disclosed is a multiple combustion mode engine with ammonia fuel including an cylinder head, a cylinder sleeve, a piston, a main combustion chamber, an inlet valve and an exhaust valve, and further including a jet ignition device arranged on the cylinder head and used for providing an ignition source for the main combustion chamber, and an ammonia injector used for providing ammonia/air mixture gas for the main combustion chamber. Also disclosed is a control method of the multiple combustion mode engine with ammonia fuel. The time sequence of ammonia injection of the main combustion chamber and jet flame generation of the pre-chamber is controlled, the mixed state of the fuel/air in the main combustion chamber before ignition can be controlled, and finally different combustion modes, i.e. a premixed combustion mode and a diffusion combustion mode, are formed in the main combustion chamber.

A fuel injection system for a spark-ignition internal combustion engine having a number of cylinders, where a plurality of respective main combustion chambers are defined; a number of first injectors and spark plugs coupled to the cylinders; a number of combustion pre-chambers, each obtained in the area of a respective spark plug; a number of extraction ducts, which originate from a respective cylinder to extract the gas mixture present inside the respective main combustion chamber; a reserve, where the gases extracted by the extraction ducts are mixed with the quantity of fuel needed to obtain a combustion under stoichiometric conditions inside the combustion pre-chambers; and a number of second injectors, each coupled to a respective combustion pre-chamber, into which it injects the gas-and-fuel mixture coming from the reserve.

A fuel injector assembly for an internal combustion engine includes a proximal end portion, a distal end portion, and a fuel injector extending at least to the distal end portion, the fuel injector including a fuel opening. The fuel injector assembly also includes a chamber formed between the proximal and distal end portions, a flame passage extending from the chamber to the distal end portion, and an atomizer configured to provide atomization of liquid fuel injected into the chamber.

Methods and systems are provided for injecting gaseous fuel during an engine start. In one example, a method comprises generating gaseous fuel via a fuel gasification device and injecting the gaseous fuel via a fuel injector. The fuel injector is configured to inject adjacent to an ignition device.

The present disclosure relates to a method for operating a combustion engine. A main amount of gas fuel is fed via a pre-chamber into a main combustion chamber. An ignition quantity of gas fuel is fed into the pre-chamber before the piston reaches the upper dead center to form an air-gas fuel mixture in the pre-chamber, which is fatter than in the main combustion chamber. The air-gas fuel mixture in the pre-chamber ignites itself. The air-gas fuel mixture in the main combustion chamber ignites through the self-ignited air-gas fuel mixture in the pre-chamber.

An internal combustion engine including a pre-chamber connected to a pre-chamber feed conduit for supplying the pre-chamber with a fuel (F), and a main combustion chamber. Fuel (F) in the main combustion chamber can be ignited by an ignition flare which passes from the at least one pre-chamber into the at least one main combustion chamber and which is produced by ignition of fuel (F) in the pre-chamber. At least one valve can be open-loop or closed-loop controlled by an open-loop or closed-loop control device depending on a parameter characteristic of a change in a power produced by the internal combustion engine, and/or by which a pre-chamber fuel flow directed through the pre-chamber feed conduit to the at least one pre-chamber can be at least partially diverted into a volume separate from the at least one pre-chamber.

A prechamber assembly includes a cylinder head including a coolant cavity, a prechamber body located within the cylinder head, the prechamber body including a nozzle, and an annular sleeve radially surrounding a portion of the prechamber body. The sleeve includes a plurality of coolant inlet holes. A portion of the prechamber body is radially spaced from the sleeve to form a coolant sleeve annulus extending along a length of the prechamber body above the coolant inlet holes. The coolant cavity and the coolant sleeve annulus are in fluid communication through the plurality of coolant inlet holes.

To meet both a request to improve the thermal efficiency in medium load operation of an engine and a request to suppress knocking in high load operation of the engine, the engine includes a main combustion chamber including a cylinder block, a cylinder head, and a piston; a pre-chamber having a plurality of injection holes that open into the main combustion chamber; and a spark plug that ignites an air-fuel mixture in the pre-chamber. A compression ratio of the main combustion chamber is not less than 14 and not more than 24, an aperture ratio, which is the ratio of a total cross-sectional area of the plurality of injection holes to a volume of the pre-chamber, is not less than 0.0078 mm.sup.-1 and not more than 0.0145 mm.sup.-1, and the volume of the pre-chamber 15 is not less than 0.0430 cm.sup.3 and not more than 0.5631 cm.sup.3.

Methods and systems are provided for injecting gaseous fuel during an engine start. In one example, a method comprises generating gaseous fuel via a fuel gasification device and injecting the gaseous fuel via a fuel injector. The fuel injector is configured to inject adjacent to an ignition device.