Internal combustion engine comprising at least one cylinder and a piston supported for repeated reciprocal movement in the cylinder so as to define a combustion chamber of an engine bore diameter A-A, the internal combustion engine further comprising an ignition device arranged in said cylinder having an igniter portion and an fuel injector which are both arranged in a pre-chamber, wherein the pre-chamber comprises a plurality of orifices for providing fluid communication between said pre-chamber and the combustion chamber, and wherein the plurality of orifices are of an overall orifice area so that the ratio between the overall orifice area and the engine bore diameter A-A ranges from 0.01 mm to 0.2 mm.

A method for operating a spark ignited gaseous fuel internal combustion engine is disclosed. The engine may have at least one main combustion chamber and at least one ignition device configured to initiate an ignition event within an ignition region. The method may include supplying pressurized fuel to the ignition region at times between about 30° to about 0° crank angle before the ignition event is initiated by the ignition device for enriching the ignition region with fuel. The method may also include initiating an ignition event in the ignition region for combusting an enriched air/fuel mixture within the ignition region.

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.

A method and a unit for operating or for the operation of a fuel metering system of an internal combustion engine, in particular in a motor vehicle, and it being provided, in particular, that at least one operating variable of the internal combustion engine is detected, a dynamic operating state of the internal combustion engine is detected based on the at least one detected operating variable, and a dynamic correction to the fuel metering system of the internal combustion engine is carried out for a detected dynamic operating state of the internal combustion engine, taking into account the efficiency of an NOx exhaust gas aftertreatment system.

Methods and systems are provided for transferring hot, compressed gases from one cylinder to another cylinder while fuel injection in both cylinders is deactivated. In one example, a method may include during a fuel shut-off event, opening a first pre-chamber injector of the first cylinder undergoing late compression or early expansion and opening a second pre-chamber injector of the second cylinder undergoing a late expansion and/or exhaust stroke or undergoing an intake stroke to allow a hot, compressed gas from the first cylinder to transfer to the second cylinder through the first and second pre-chamber injectors.

A fuel ignition device for an engine having a plurality of cylinders. The fuel ignition device including an active pre-chamber, the active pre-chamber further including a fuel inlet for introducing fuel into the active pre-chamber, a spark plug configured to ignite a fuel-air mixture in the active pre-chamber, and a plurality of holes arranged circumferentially around a lower end of the active pre-chamber, the plurality of holes being configured to provide fluid communication between the central chamber and a combustion main chamber of the gas engine.

The present invention relates to a device and a method for controlling the start of an internal combustion engine, wherein the internal combustion engine is equipped with an ignition device comprising a fuel-fed prechamber to ignite an air-fuel mixture in a main combustion chamber. In order to reduce the emissions of the internal combustion engine during engine start a prechamber heating operations is performed by injecting a predetermined amount of fuel into the prechamber and igniting an air-fuel-mixture therein, while the main fuel injector is deactivated during at least a first engine cycle after engine start request.

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.

Methods and systems are provided for operating a cylinder of an engine including a pre-chamber system. In one example, a method includes flowing gases from a pre-chamber to a cylinder of an engine prior to fueling the cylinder during a combustion cycle, adjusting a composition of the gases by adjusting at least one of an air injection amount to the pre-chamber and a fuel injection amount to the pre-chamber, and igniting an air-fuel mixture in the cylinder via a pre-chamber ignition event, the air-fuel mixture in the cylinder including the gas from the pre-chamber. In this way, combustion qualities in the cylinder may be adjusted in order to increase a performance and/or an efficiency of the cylinder.

Provided is a subchamber diesel engine having excellent thermal efficiency and capable of appropriately controlling the ignition timing of fuel supplied to a combustion subchamber. A subchamber diesel engine according to the present invention comprises a main combustion chamber and a combustion subchamber communicated with each other by a communication hole, the diesel engine including: an electrically driven injector for injecting fuel into the combustion subchamber at a random timing; a fuel passage pipe connected to a fuel inlet of the injector; a fuel pump for supplying fuel to the fuel passage pipe; an engine operating state detector for detecting an engine operating state; and a controller, wherein the controller performs a preliminary fuel injection in the first half of an intake stroke, performs a main injection during a compression stroke, and after the main injection, performs an ignition control injection near a compression top dead center.