Systems, devices, and methods described herein provide one or more radical chemicals generators (RCGs) and/or mini-chambers (M-Cs) that can be used to provide enhanced radical ignition (ERI) in an internal combustion engine. RCGs as described herein can include quenching systems (QSs) that can be configured to quench a flame of combustion products to produce a jet of partial combustion products containing radical species (RS). The jet of partial combustion products can be injected to a main combustion chamber (MCC) of an engine to induce ERI. ERI can proceed under leaner fuel conditions and lower temperatures compared to those needed for conventional thermally induced, fuel oxidation chain initiation reaction processes.

An internal combustion engine generally includes at least a cylinder; at least an intake valve acting on an intake port for controlling the airflow entering the cylinder; at least an injector for supplying uncombusted fuel to the cylinder; at least an outlet valve acting on a respective outlet port for controlling the flow of the exhaust gases at the outlet of the cylinder; a piston sliding in a linear manner within the cylinder; at least a first spark plug arranged in a position adjacent to the injector and acting within the combustion chamber; a pre-chamber communicating with the combustion chamber; and a second spark plug acting within the pre-chamber; the first spark plug is arranged in an intermediate position between the pre-chamber and the injector.

An engine system is provided, which includes a cylinder block, a cylinder head, a piston, a main combustion chamber, a subchamber, an injector that injects fuel into the main combustion chamber, a main spark plug that ignites a mixture gas inside the main combustion chamber, a subspark plug that ignites the mixture gas inside the subchamber, and a controller electrically connected to the injector, the main spark plug and the subspark plug. When an engine speed is above a given reference engine speed, the controller controls, in a low-load range below a given reference load, the ignition devices so that the subignition is performed after the main ignition, and the controller controls, in a high-load range exceeding the reference load, the ignition devices so that only the subignition is performed, or so that the main ignition is performed at the same timing as or after the subignition.

Operating a gaseous fuel engine includes spark-igniting gaseous hydrogen fuel and air, and propagating combustion gases of the spark-ignited mixture outwardly from a spark gap. The propagating combustion gases are impinged upon a cone surface of a piston so as to limit a flame area of the propagating combustion gases. Additional gaseous hydrogen fuel and air is ignited in the combustion cylinder by way of the propagating combustion gases to urge a piston toward a bottom-dead-center position.

An internal combustion engine comprising: at least a cylinder; at least an intake valve acting on an intake port for controlling the airflow entering the cylinder; at least an injector for supplying uncombusted fuel to the cylinder; at least an outlet valve acting on a respective outlet port 18 for controlling the flow of the exhaust gases at the outlet of the cylinder; a piston sliding in a linear manner within the cylinder; at least a first spark plug arranged in a position adjacent to the injector and acting within the combustion chamber; a pre-chamber communicating with the combustion chamber; and a second spark plug acting within the pre-chamber; the first spark plug is arranged in an intermediate position between the pre-chamber and the injector.

An ignition device configured to ignite a fuel included in an air-fuel mixture supplied to a main combustion chamber of an internal combustion engine. The ignition device includes a partition member that forms a precombustion chamber that encloses an ignition point of a fuel. The partition member has a plurality of communicating holes communicating between the main combustion chamber and the precombustion chamber. The ignition device further includes a first interference member that protrudes inward from an inner surface of the partition member.

A method includes forming a combustible mixture by mixing generally homogeneously a first fuel and air and introducing this mixture into a cylinder, compressing the combustible mixture with a piston in a compression stroke, introducing a second fuel into a prechamber at an introduction-time before start of combustion thus creating a prechamber charge, in which the second fuel being of the same or different chemical composition and/or concentration with respect to the first fuel, and spark igniting the prechamber charge. Emission of the cylinder and/or mechanical stress of the cylinder caused by the combustion are monitored. If emissions and/or mechanical stress are above respective predetermined thresholds, individually for the at least one cylinder, the chemical composition and/or the amount of second fuel introduced into the prechamber, and/or temperature of the cylinder charge and/or spark timing, are changed.

An internal combustion engine may include a combustion chamber which is delimited by a cylinder; an injector with which fuel can be injected into the combustion chamber, whereby a mixture comprising fuel and air can be generated in the combustion chamber; a pre-chamber, which is fluidically separate from the combustion chamber with the exception of a passage opening and which is fluidically connected to the combustion chamber via the passage opening; a first spark plug with which an ignition spark can be produced in the pre-chamber; and a second spark plug with which an ignition spark can be produced in the combustion chamber and outside of the pre-chamber, wherein the pre-chamber, the injector, and the second spark plug are arranged, in this order, in a direction extending in a plane that is perpendicular to the axial direction of the cylinder.

An internal combustion engine including at least one combustion chamber having a main chamber and a prechamber, wherein the prechamber is in fluid connection with the main chamber via at least one bore. The at least one combustion chamber is connected to a charging path for the supply of a combustion air-fuel mixture into the combustion chamber via the charging path. A fuel intermixing region is arranged in a section of the charging path separately assigned to the combustion chamber, which fuel intermixing region is in fluid connection with the charging path on one side and with a fuel line on the other side for the supply of fuel into the fuel intermixing region via a controllable fuel valve. The internal combustion engine wherein the prechamber and the fuel intermixing region are in fluid connection with one another via a check valve.

A method of combusting fuel, e.g. heavy fuel, in a rotary engine, including injecting a main quantity of fuel directly into a combustion chamber to form a first fuel-air mixture having a first air-fuel equivalence ratio higher than 1, injecting a pilot quantity of fuel into a pilot subchamber to form a second fuel-air mixture having a second air-fuel equivalence ratio smaller than the first air-fuel equivalence ratio, igniting the second fuel-air mixture within the pilot subchamber, using the ignited second fuel-air mixture from the pilot subchamber to ignite the first fuel-air mixture, and injecting a supplemental quantity of fuel directly into the combustion chamber after igniting the first fuel-air mixture, upstream of an exhaust port of the rotary engine with respect to a direction of rotation of the rotor. A rotary engine with interburner fuel injector is also discussed.