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.

A method for operating an internal combustion engine including feeding a pilot quantity of gas fuel, into a prechamber before a piston reaches a top dead center position. The method comprises autoignition of the pilot quantity of gas fuel in the prechamber, feeding a main quantity of gas fuel into the prechamber after the autoignition, and ignition of the main quantity of gas fuel by the conditions in the prechamber that are brought about by the autoignited pilot quantity. The method makes it possible to operate an internal combustion engine purely with methane or some other gaseous fuel, by means of compression autoignition of the pilot quantity.

An internal combustion engine includes including a fuel reformation cylinder for reforming a fuel and an output cylinder for yielding an engine power by combusting a fuel or a reformed fuel, wherein at least a part of the surfaces constituting a volume-variable reaction chamber of the fuel reformation cylinder has a highly heat-insulative material.

An internal combustion engine including a fuel reformation cylinder for reforming a fuel and an output cylinder for yielding an engine power by combusting a fuel or a reformed fuel, wherein at least a part of the surfaces constituting a volume-variable reaction chamber of the fuel reformation cylinder has a highly heat-insulative material.

A method for operating an internal combustion engine including feeding a pilot quantity of gas fuel, into a prechamber before a piston reaches a top dead center position. The method comprises autoignition of the pilot quantity of gas fuel in the prechamber, feeding a main quantity of gas fuel into the prechamber after the autoignition, and ignition of the main quantity of gas fuel by the conditions in the prechamber that are brought about by the autoignited pilot quantity. The method makes it possible to operate an internal combustion engine purely with methane or some other gaseous fuel, by means of compression autoignition of the pilot quantity.

An apparatus and method are disclosed for an injector assembly including an injector tip having a prechamber, such as a permanent, passive prechamber (PPPC), and a nozzle combustion shield (NCS) to mitigate pre-ignition events, such as knocking, caused by overheating of the prechamber. The NCS has a thermal conductivity greater than the injector tip. The NCS optionally includes a barrel forming a slip fit with the cylinder head bore and forming a press fit with the injector tip. The NCS also optionally includes a brim to form a combustion seal with a cylinder head. As the spark plug ignites a fuel charge in the prechamber, heat is absorbed into the injector tip, flows into the NCS barrel, out of the NCS brim, and into the cylinder head for cooling via a cooling jacket.

Disclosed is a prechamber device for a combustion engine. The prechamber device comprises a prechamber body circumferentially enclosing a prechamber cavity, a nozzle body extending from the prechamber body and disposed at a first axial end of the prechamber device, wherein an interior of the nozzle body is in fluid communication with and provides an appendix of the prechamber cavity. The prechamber body and the nozzle body are provided as a wall comprising an inner surface and an outer surface and comprise a first material. A core member of a second material is enclosed inside the wall between the inner surface and the outer surface and axially extending inside the nozzle body, enclosed by the first material.

An internal combustion engine (1) including a fuel reformation cylinder (2) for reforming a fuel and an output cylinder (3) for yielding an engine power by combusting a fuel or a reformed fuel, wherein at least a part of the surfaces constituting a volume-variable reaction chamber (23) of the fuel reformation cylinder (2) has a highly heat-insulative material (10).

A prechamber ignition device in an internal combustion engine is provided having a body piece formed of a first type of material and a tip piece formed of a second type of material. A distal end of the body piece has a cladding, which may be of the second type of material, for preventing corrosion of the first type of material from which the body piece is formed.

An apparatus and method are disclosed for an injector assembly including an injector tip having a prechamber, such as a permanent, passive prechamber (PPPC), and a nozzle combustion shield (NCS) to mitigate pre-ignition events, such as knocking, caused by overheating of the prechamber. The NCS has a thermal conductivity greater than the injector tip. The NCS optionally includes a barrel forming a slip fit with the cylinder head bore and forming a press fit with the injector tip. The NCS also optionally includes a brim to form a combustion seal with a cylinder head. As the spark plug ignites a fuel charge in the prechamber, heat is absorbed into the injector tip, flows into the NCS barrel, out of the NCS brim, and into the cylinder head for cooling via a cooling jacket.