An air-assisted jet flame ignition device includes a housing, a fuel-air premixing unit, and a prechamber. The fuel-air premixing unit includes a fuel injector, an air injection valve, a premixing sleeve, a premixing sleeve inner core placed in the premixing sleeve, and a fuel injector fastening bolt. An inner wall surface of the premixing sleeve and an outer wall surface of the premixing sleeve inner core form a premixing sleeve inner cavity. An inner wall surface of the premixing sleeve inner core, a lower end surface of a nozzle of the fuel injector, and an upper end surface of an air inlet of the air injection valve form a premixing cavity. The premixing cavity coupled to the premixing sleeve inner cavity via a through hole on the sidewall of the premixing sleeve inner core. A prechamber nozzle is fixedly coupled to the lower part of the housing.

A method for starting an internal combustion engine comprises the steps of: providing an internal combustion engine having at least one cylinder and a piston supported at a crankshaft for repeated reciprocal movement in the cylinder so as to define a main combustion chamber, the internal combustion engine further having an ignition device arranged in said cylinder with an igniter portion and a fuel injector which are both arranged at a pre-chamber, wherein the pre-chamber has a plurality of orifices for providing fluid communication between said pre-chamber and the main combustion chamber, injecting fuel in the pre-chamber, and igniting the injected fuel in the pre-chamber for pre-heating of the pre-chamber prior to injecting fuel in the main combustion chamber for combusting the injected fuel in the main combustion chamber.

A fuel injector is configured so that, when seen from a top view of a combustion chamber, a first fuel spray flux and a second fuel spray flux sandwich an electrode part of a spark plug, and the electrode part is located outside of contour surfaces of the two fuel spray fluxes. A first injection angle between a center line of the first fuel spray flux and a vertical line and a second injection angle between a center line of the second fuel spray flux and the vertical line are larger than an angle between a center line of any other fuel spray flux and the vertical line. The second injection angle is made smaller than the first injection angle so that a distance from the electrode part to the contour surface of the second fuel spray flux is larger than a distance from the electrode part to the contour surface of the first fuel spray flux.

A fuel injector is configured so that, when seen from a top view of a combustion chamber, a first fuel spray flux and a second fuel spray flux sandwich an electrode part of a spark plug, and the electrode part is located outside of contour surfaces of the two fuel spray fluxes. A first injection angle between a center line of the first fuel spray flux and a vertical line and a second injection angle between a center line of the second fuel spray flux and the vertical line are larger than an angle between a center line of any other fuel spray flux and the vertical line. The second injection angle is made smaller than the first injection angle so that a distance from the electrode part to the contour surface of the second fuel spray flux is larger than a distance from the electrode part to the contour surface of the first fuel spray flux.

A compression ignition engine may operate using autoignition resistant fuels by laser-assisted ignition where a focused laser beam directly heats a spray of fuel proximate to an injector nozzle to promote a lifted flame combustion avoiding knock that could occur with the ignition of premixed fuel.

A compression ignition engine may operate using autoignition resistant fuels by laser-assisted ignition where a focused laser beam directly heats a spray of fuel proximate to an injector nozzle to promote a lifted flame combustion avoiding knock that could occur with the ignition of premixed fuel.

An air-assisted jet flame ignition device includes a housing, a fuel-air premixing unit, and a prechamber. The fuel-air premixing unit includes a fuel injector, an air injection valve, a premixing sleeve, a premixing sleeve inner core placed in the premixing sleeve, and a fuel injector fastening bolt. An inner wall surface of the premixing sleeve and an outer wall surface of the premixing sleeve inner core form a premixing sleeve inner cavity. An inner wall surface of the premixing sleeve inner core, a lower end surface of a nozzle of the fuel injector, and an upper end surface of an air inlet of the air injection valve form a premixing cavity. The premixing cavity coupled to the premixing sleeve inner cavity via a through hole on the sidewall of the premixing sleeve inner core. A prechamber nozzle is fixedly coupled to the lower part of the housing.

An internal combustion engine has fuel injectors for a first fuel and separate fuel injector-igniters for a second fuel. The first fuel may be a compression-ignition fuel such as diesel fuel while the second fuel is a lower cetane fuel that requires external energy for controlled ignition. For example, the second fuel may be natural gas. Such engines have applications in a wide range of fields, particularly those fields requiring large-displacement slow- and medium-speed engines. Such engines are particularly well adapted for use in railway locomotives. A locomotive equipped with such an engine may operate primarily on natural gas, and thereby take advantage of the significant price difference between natural gas and diesel fuel, while permitting switch over to operation on 100% diesel fuel.

An internal combustion engine has fuel injectors for a first fuel and separate fuel injector-igniters for a second fuel. The first fuel may be a compression-ignition fuel such as diesel fuel while the second fuel is a lower cetane fuel that requires external energy for controlled ignition. For example, the second fuel may be natural gas. Such engines have applications in a wide range of fields, particularly those fields requiring large-displacement slow- and medium-speed engines. Such engines are particularly well adapted for use in railway locomotives. A locomotive equipped with such an engine may operate primarily on natural gas, and thereby take advantage of the significant price difference between natural gas and diesel fuel, while permitting switch over to operation on 100% diesel fuel.

An internal combustion engine, includes at least one cylinder, wherein the or each cylinder includes a main combustion chamber for burning fuel in the cylinder, wherein an assembly serving to supply and/or ignite fuel is installed on a cylinder head of each cylinder between gas exhaust valves of the cylinder in such a way that the assembly is inserted into a cut-out in the cylinder head of the cylinder and is sealed to said cut-out, wherein a segment of the assembly that is inserted into the cut-out in the cylinder head of the cylinder has an oval contour in the cross-section, and wherein a bounding surface of said segment of the assembly, which bounding surface lies in the sealing region, is contoured in such a way that said bounding surface is continuously convexly curved outward in the peripheral direction.