The present invention relates to a gas intake device (1) for a cylinder of an internal-combustion engine. The gas intake device comprises two intake pipes (5a, 5b), two intake valves (4), two intake valve calibration parts (6a, 6b) and, in each intake pipe (5a, 5b), means for forming an aerodynamic gas motion of tumble type in the cylinder. Furthermore, for each intake pipe (5a, 5b), the intersection between intake pipe (5a, 5b) and calibration part (6a, 6b) occurs along a line non-parallel to the plane of the fire face. Besides, the inclination angle of this intersection is different for each pipe (5a, 5b).

Examples are directed to a fuel injection device positioned in a cylinder liner. In one example, a cylinder includes a combustion chamber which is jointly formed by a piston crown of a piston, by a cylinder barrel which laterally delimits the combustion chamber, and by a cylinder head. The cylinder includes an injection device positioned in the cylinder barrel for direct introduction of fuel into the combustion chamber, which injection device has at least one opening which, during a course of an injection process, is configured to be activated to introduce fuel into the combustion chamber, the injection device terminating flush, at a combustion chamber side, with the cylinder barrel.

An intake stroke injection and a compression stroke injection are performed during catalyst warm-up control (upper section in FIG. 7). During the catalyst warm-up control, a discharge period at an electrode portion is set on a retard side of compression top dead center, and an expansion stroke injection is performed during the discharge period. However, when a distance between a spray contour surface and the electrode portion increases, an additional injection (first injection) is performed in advance of the expansion stroke injection (second injection) (lower section in FIG. 7). The additional injection is performed at a timing that is on the retard side of compression top dead center and is on an advance side relative to a start timing of the discharge at the electrode portion.

A control device is configured to perform, when it is estimated that a combustion fluctuation increases, estimation related to an ignition delay for initial flame generated from a discharge spark and an air-fuel mixture containing fuel spray injected by intake stroke injection. When it is estimated that the ignition delay for the initial flame is increased from that before the increase in the combustion fluctuation, an injection amount in expansion stroke injection is reduced in a next time cycle. When it is estimated that the ignition delay for the initial flame is reduced from that before the increase in the combustion fluctuation, the injection amount in expansion stroke injection is increased in a next time cycle.

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.

A cylinder head of an engine in which a thermal stress acting between a valve seat made of clad material and a base metal is reduced. The cylinder head comprises: an inner wall surface; a pair of intake ports arranged adjacent to each other; a valve seat formed of clad material around each intake port; a mask section formed within a predetermined range of a circumference of each intake port to protrude toward a combustion chamber; and a cavity formed between a pair of the mask sections by partially depressing the inner wall surface toward the combustion chamber.

A hydrogen intake assembly for a hydrogen internal combustion engine characterized in that the hydrogen intake assembly includes at least one air intake manifold comprising an air intake pipe comprising at least one air inlet and air outlets, air intake runners comprising air inlets and air outlets, a spacer having a wall defining an inner chamber receiving a mixture of air, water and hydrogen and comprising air inlets and mixture outlets delivering said mixture, a water rail comprising at least one water inlet and water outlets, said water outlets being embedded in the wall of the spacer and a hydrogen rail comprising at least a hydrogen inlet and hydrogen outlets.

In a control method of an internal combustion engine including a fuel injection valve having a plurality of injection holes and adapted to directly inject a fuel into a cylinder and an ignition plug adapted to generate a plug discharging channel, after fuel injection is performed, spark ignition is performed while turbulence in an air flow is generated by the fuel injection by an ignition plug disposed so that a discharging region is sandwiched by fuel sprays injected from the two adjacent injection holes and located within a range where the turbulence in the air flow is generated.

A far square or diamond architecture engine with tumble flow to support spark-ignited fuel usage. The engine may be provided in a configuration generally suited for swirl flow, compression combustion fuel usage. However, the introduction of a unique, replaceable valve head assembly may be utilized to induce tumble flow within a combustion chamber of the engine. Thus, spark-ignited fuel may be utilized without requiring vast overhaul of the engine to accommodate such fuels. Notably, with the addition of such an assembly, diesel fuel may be replaced with natural gas on large scale equipment without the requirement of impractically burdensome or expensive measures.

An internal combustion engine for a motor vehicle includes a combustion chamber in which a first tumble-shaped current of a fuel-air mixture is settable. A pre-chamber spark plug is allocated to the combustion chamber which has a pre-chamber which is fluidically connected to the combustion chamber via a plurality of openings where via the plurality of openings a part of the fuel-air mixture flows out of the combustion chamber and into the pre-chamber. The plurality of openings are formed such that the part of the fuel-air mixture that flows into the pre-chamber via the plurality of openings has a second tumble-shaped current where the second tumble-shaped current is opposite to the first tumble-shaped current.