A two-stroke engine according to the present invention includes: a separating wall which confines a tip end portion of an ignition device; an ignition promoting chamber which is formed by means of the separating wall, is independent of a combustion chamber, and encloses the tip end portion of the ignition device; and a plurality of communicating holes which are provided in the separating wall, each of which is provided with a first opening that opens in the combustion chamber and a second opening that opens in the ignition promoting chamber, and which provide communication between the combustion chamber and the ignition promoting chamber.

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.

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.

To provide an engine capable of more quickly decreasing an auxiliary chamber gas pressure and ensuring a favorable load responsiveness. A gas engine is an engine including, as combustion chambers of each cylinder, an auxiliary chamber that ignites fuel gas to generate flame and a main chamber that combusts the mixture of fuel gas and air using the flame generated in the auxiliary chamber, and includes an auxiliary chamber main pipe that supplies the fuel gas to the auxiliary chamber, an air supply passage in which the air to be supplied to the main chamber flows, and a connection pipe communicating from the auxiliary chamber main pipe to the air supply passage.

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.

A pre-chamber arrangement (100) for a gas engine (1), including a pre-chamber body (20) accommodating a volume (30); and a supply device (50) for supplying a gaseous medium (52) into the pre-chamber volume (30); wherein the pre-chamber body (20) has a bottom portion (22) with channels (40) for allowing gas to flow between the pre-chamber volume (30) and a main combustion chamber (10) of the gas engine (1). Each channel (40) extends along a channel axis (C) from an inner opening (42) facing the pre-chamber volume (30) to an outer opening (44) configured to face the main combustion chamber (10). The bottom portion (22) has a curved outer surface (24). The channels (40) are obliquely arranged in relation to a radius (r) of the bottom portion (22). The bottom portion has flat surfaces (46) surrounding the outer openings of the channels.

Systems and methods for starting and operating a direct injection engine are described. In one example, the air and fuel are injected into a pre-chamber of a cylinder of an engine while the engine is not rotating. The air and fuel are combusted in the pre-chamber to improve ignition of an air and fuel mixture in the cylinder.

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 λ 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 λ 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.

To meet both a request to improve the thermal efficiency in the medium load operation of an engine and a request to suppress knocking in the high load and high rotation operation of the engine, the engine includes a main combustion chamber comprising a cylinder block, a cylinder head, and a piston; a pre-chamber having a plurality of injection holes that open into the main combustion chamber; and a spark plug that ignites an air-fuel mixture in the pre-chamber. A compression ratio of the main combustion chamber is not less than 14 and not more than 24. A first index, which is the product between a total cross-sectional area of the plurality of injection holes and the compression ratio, is not less than 0.1496 cm.sup.2 and not more than 0.8449 cm.sup.2.

To effectively suppress strong knock that occurs in the operating region of high load and high rotation in a specific engine having a pre-chamber in a combustion chamber, the engine includes a piston that defines a combustion chamber together with a cylinder block and a cylinder head. The combustion chamber includes a sub-chamber and a main chamber separated from the sub-chamber by a pre-chamber. The specific ratio obtained by dividing a volume of the sub-chamber by a stroke volume of a cylinder is greater than or equal to 0.00005 and less than or equal to 0.00045.