A metering valve or an injector includes: a valve-seat member which closes a valve chamber and has a central valve opening, and a spray orifice disk downstream from the valve-seat member in the flow direction of the fluid, which has at least one spray orifice. The spray orifice disk has a swirl chamber concentric with the spray orifice and at least one swirl duct leading from the swirl chamber to beneath the valve opening, and the swirl chamber and swirl duct are integrally formed as recesses into the disk surface of the spray orifice disk facing the valve body. The swirl duct has a duct cross section and the spray orifice has an orifice cross section such that the ratio of the duct cross section to the orifice cross section is equal to or greater than 1.5.

A ducted combustion system is disclosed. The ducted combustion system includes a combustion chamber bound by a flame deck surface of a cylinder head of an internal combustion engine and by a piston top surface of a piston disposed within the internal combustion engine. The system includes a fuel injector including one or more orifices, the one or more orifices injecting fuel into the combustion chamber as one or more fuel jets. The system includes one or more ducts disposed within the combustion chamber between the flame deck surface and the piston top surface, the one or more ducts being generally tubular shaped structures and being disposed such that each of the one or more fuel jets at least partially enters one of the one or more ducts upon being injected into the combustion chamber.

A fuel injection nozzle includes: a nozzle body having a plurality of injection holes; and a needle accommodated in the nozzle body to inject a DME fuel containing dimethyl ether as a main component. The nozzle body has a seat part to which the needle seated or from which the needle separated, and a tip end chamber arranged downstream of the seat part in a flow of the DME fuel to communicate with the plurality of injection holes. The DME fuel in the tip end chamber is heated with combustion heat in a combustion chamber of an internal combustion engine to have a supercritical state.

A nozzle for a member of a fuel combustion system of an engine includes a hollow nozzle body. The nozzle body includes an outer surface, an inner surface, and an orifice surface. The outer surface defines an outer opening. The inner surface defines an interior chamber and an inner opening. The orifice surface defines an orifice passage extending between, and in communication with, the outer opening and the inner opening. The orifice passage is in communication with the interior chamber via the inner opening. The orifice surface includes a boundary surface and a protrusion. The protrusion projects from the boundary surface radially inwardly into the orifice passage.

A fuel injection device includes a nozzle element, an injection hole forming member, and a valve element. The injection hole forming member includes a seat part having the seat surface, and a suck chamber formed on a front end part of the seat part, the suck chamber being a recess denting in the direction of heading from the seat surface toward a front end part. The suck chamber has a suck chamber injection hole from which a fuel is jetted toward the ignition plug.

A nozzle body of a fuel injector includes a proximal end, a distal end spaced apart from the proximal end, and at least one spray hole positioned at the distal end. The at least one spray hole includes an inlet having a first cross-sectional shape and an outlet having a second cross-sectional shape different from the first cross-sectional shape. In other embodiments, the nozzle body has a first row of spray holes and a second row of spray holes, and a cross-sectional shape of spray holes in the first row is different from the cross-sectional shape of spray holes in the second row.

An apparatus and method for injection of a pilot fuel and a gaseous fuel into an internal combustion engine, the method including injecting a quantity of pilot fuel, a quantity of pilot gaseous fuel and a main quantity of the gaseous fuel into the combustion chamber; igniting and burning the pilot fuel to create a pressure and temperature environment in the combustion chamber; igniting and burning the pilot quantity of the gaseous fuel due to the pressure and temperature environment in the combustion chamber due to the burning of the pilot fuel; and igniting and burning the main quantity of the gaseous fuel due to the pressure and temperature environment in the combustion chamber due to the burning of the pilot quantity of the gaseous fuel.

A fuel injector nozzle (9) is disclosed. The nozzle (9) comprises a nozzle tip (9) comprising an inner surface (39) and an outer surface (41). The nozzle (9) further comprises a number of fuel injection holes (11) each forming an inlet opening (31) at the inner surface (39) and an outlet opening (32) at the outer surface (41). At least one fuel injection hole (11) has a geometrical centre line (c1) being curved along at least a first portion (p1) of the at least one fuel injection hole (11). The radius of curvature (r1) of the geometrical centre line (c1) increases as seen in a direction (d1) from the inlet opening (31) towards the outlet opening (32). The radius of curvature (r1) increases continuously along the full first portion (p1) of the at least one fuel injection hole (11) as seen in the direction (d1) from the inlet opening (31) towards the outlet opening (32). A fuel injector (1), an internal combustion engine (40), and a vehicle (2) are also disclosed.