Operating a gaseous fuel engine system includes urging a mixture containing a gaseous hydrogen fuel and air into a pocket in an igniter fluidly connected to a cylinder to form an ignition charge, and igniting the ignition charge via a flame kernel formed by energizing spark electrodes of the igniter. The method further includes igniting a main charge containing the gaseous hydrogen fuel via a flame jet of the ignition charge from the igniter. The pocket is shielded from the cylinder sufficiently to form within the pocket a flow field protecting the flame kernel, while fluidly connected to the cylinder sufficiently to clear the pocket of residual combustion gases.

A prechamber assembly for an internal combustion engine is disclosed. The prechamber assembly may have a prechamber housing with a first prechamber housing portion and a second prechamber housing portion. The first prechamber housing portion and the second prechamber housing portion may define a prechamber volume. The prechamber assembly may also have a cooling system. The cooling system may be configured to cool at least one of the first prechamber housing portion and the second prechamber housing portion based on a flow of a cooling fluid through the cooling system. The cooling system may have at least one cooling channel formed within the prechamber housing.

The present invention pertains to arrangements for a pre-chamber of a combustion engine as well as pre-chambers comprising such arrangements, in particular to avoid or impair backfiring or flashbacks of a combustible mixture and/or to enable a flame retardation within a respective pre-chamber. Accordingly, an arrangement for a pre-chamber gas valve of a combustion engine, preferably a gas engine, is suggested, which comprises a housing having an outer surface and comprising a channel, wherein a first end of the channel is in fluid communication with the outer surface and a second end of the channel is connectable to a valve seat of the pre-chamber gas valve. The arrangement furthermore comprises a plurality of protrusions extending radially outward from the outer surface of the housing. The first end of the channel is arranged upstream of the second end of the channel and downstream of the protrusions, wherein the protrusions are spaced apart from each other in a circumferential direction and define a respective cavity between respective adjacent protrusions, each cavity having an extension being larger in a radial direction and/or axial direction than an extension in the circumferential direction.

The invention relates to an engine having prechamber ignition, in particular a gas engine, that comprises a main combustion space in a cylinder of the engine for combusting an air-fuel mixture and a prechamber having an ignition device arranged therein and a fuel injector arranged therein, wherein the prechamber has at least one transfer port that fluidically connects the prechamber to the main combustion space. The engine is characterized in that the fuel injector arranged in the prechamber is the only fuel injector via which fuel can be introduced into the associated main combustion space.

A prechamber spark plug. The spark plug includes a housing, a cap, which defines a prechamber at least partially, and which includes a plurality of through holes that are configured to produce a connection between the prechamber and a combustion chamber of an internal combustion engine; the through holes each having a hole center line; the cap including a recess at a region pointed towards the housing, the recess abutting the housing at a combustion-chamber-side end of the housing; a distance from an exit point of a through hole lying on the hole center line, to a recess, being in a range of 2 mm to 7 mm; and a first angle between a center axis of the prechamber spark plug and the hole center line being in a range of 30? to 70?. An internal combustion engine including such a prechamber spark plug is also described.

An engine has, for each cylinder, a combustion chamber and a combustion pre-chamber communicating with the combustion chamber. First and second spark plugs are associated with the pre-chamber and combustion chamber, respectively. Gasoline is injected by an injector device directly into the combustion chamber and/or by an injector device into a cylinder intake duct. There is no device for injecting gasoline, air or an air/gasoline mixture directly into the pre-chamber. The engine operates with an air/gasoline mixture substantially corresponding to stoichiometric for compatibility with an exhaust system having a trivalent catalyst. The pre-chamber is, not used for engine operation with poor dosing, but to increase resistance to engine detonation. The engine can thus be configured with a high compression ratio, with a significant reduction in fuel consumption at the same power level. The second spark plug is only activated at low and medium engine loads to stabilize combustion.

A pre-chamber body for an internal combustion engine is disclosed. The pre-chamber body may have a pre-chamber. The pre-chamber body may also have a flow transfer passage, which may fluidly connect the pre-chamber and an exterior of the pre-chamber body. In addition, the pre-chamber body may have at least one backflow channel, which may fluidly connect the pre-chamber and the flow transfer passage.

In certain embodiments with large size prechambers and/or with prechambers that have large spark-gap electrode assemblies, a poor scavenge of the crevice volume may cause deterioration of the preignition margin, which then may limit the power rating of the engine, may cause the flow velocity field of the fuel-air mixture to be excessively uneven and may result in the deterioration of the misfire limit. One or more auxiliary scavenging ports may allow admission of fuel rich mixture to the crevice volume, thereby cooling the residual gases and preventing occurrence of preignition. More organized and powerful flow velocity fields may be obtained in the spark-gap electrode assembly region. This condition may result in a significant extension of the flammability limit and may significantly improve the combustion efficiency of the prechamber. Passive prechambers using the active scavenge concept may increase the engine power output and reduce the emission of pollutants from engine combustion.

The invention relates to an engine having prechamber ignition, in particular a gas engine, that comprises a main combustion space in a cylinder of the engine for combusting an air-fuel mixture and a prechamber having an ignition device arranged therein and a fuel injector arranged therein, wherein the prechamber has at least one transfer port that fluidically connects the prechamber to the main combustion space. The engine is characterized in that the fuel injector arranged in the prechamber is the only fuel injector via which fuel can be introduced into the associated main combustion space.

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.