A control system that controls fuel injection of a diesel engine includes a split injection control module that causes a fuel injection valve to execute pre-injection for injecting fuel at a predetermined first timing, and post-injection for injecting fuel at a second timing later than the pre-injection, a setting module that sets a fuel injection amount or a fuel injection timing in the pre-injection or the post-injection so that a difference between a first peak and a second peak, which are peaks of an increase rate of combustion pressure accompanying the pre- and post-injection, falls within a predetermined range, and a calculation module that calculates the first and second peaks in an increase rate of the combustion pressure by excluding motoring pressure, which is an in-cylinder pressure at the time of non-combustion of the combustion chamber.

A fuel injection control device causes an injector to execute main injection or pilot injection toward a joint portion, and low penetration injection to inject fuel at timing earlier than the pilot injection in a PILOT region or at timing later than the main injection in an AFTER region. The fuel injection control device causes the low penetration injection to be executed to inject the fuel only in a radial central region of a combustion chamber.

A fuel injection control causes a fuel injection valve to execute at least: a main injection to inject fuel at timing when a piston is positioned near a compression top dead center; a pilot injection to inject the fuel at timing earlier than the main injection; and a low penetration injection to inject the fuel at timing earlier than the pilot injection or timing later than the main injection. The fuel injection control device includes: a first injection control module that executes at least one of the main injection or the pilot injection at timing to inject the fuel toward a joint portion of a cavity; and a second injection control module that executes the low penetration injection to inject the fuel only into a radial central region of a combustion chamber.

A piston for an internal combustion engine is disclosed. The piston is configured to reciprocate along a centre axis of the piston during operation in an engine. The piston comprises a number of fuel directing surfaces arranged at a distance from a top surface of the piston measured along the centre axis. Each fuel directing surface is configured to direct a fuel spray sprayed onto the fuel directing surface. The fuel directing surfaces are arranged with gaps between two adjacent fuel directing surfaces. The present disclosure further relates to an engine comprising a piston and a vehicle comprising an internal combustion engine.

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.

A diesel engine comprises: a cylinder head covering one end of a cylinder; a piston having a crown surface opposed to the cylinder head and reciprocatingly movable in the cylinder; and a fuel injection valve attached to the cylinder head, wherein the crown surface of the piston is formed with a cavity which is concaved toward a side opposite to the cylinder head, and has a round shape in top plan view, and the fuel injection valve is formed with a nozzle hole directed toward the inside of the cavity, and wherein a wall surface defining the cavity has a wall segment formed in a periphery of the cavity at a position deviated from a directional direction of the nozzle hole and protruding toward a radially inward side of the piston in approximately parallel to a plane including a central axis of the piston.

A fuel injector for injecting fuel vapour into a combustion chamber of an internal combustion engine. The injector has a central axis and is mountable to the internal combustion engine so that the fuel injector projects into the combustion chamber. The injector has an inlet for supplying fuel to the fuel injector. The inlet projects from the injector body at a first circumferential position of the injector body. The inlet has a component of projection, X, radially outward relative to the central axis of the injector. The injector also has a spray nozzle having a tip and the spray nozzle extends longitudinally from the injector body. The injector has a plurality of spray discharge orifices formed on the tip with an even radial distribution about the tip. Each spray discharge orifice is configured to discharge fuel vapour. Each spray discharge orifice has a component of direction parallel to the central axis and a component of direction, Y, radially outward relative to the central axis. Y is at an angle offset from X.

The diesel engine comprises: a cylinder head covering one end of a cylinder; a piston having a crown surface opposed to the cylinder head and performing a reciprocating movement within the cylinder; and a fuel injector attached to the cylinder head. The crown surface of the piston is formed with a cavity which is concaved toward a side opposite to the cylinder head and has a round shape in top plan view, and a groove concaved from a periphery of the cavity toward a radially outward side of the piston. The groove extends from the lower end on the side opposite to the cylinder head, toward the upper end on the side of the cylinder head, while inclining in a circumferential direction of the piston. The fuel injector is formed with a nozzle hole directed toward the groove.

A diesel engine includes a cylinder, a cylinder head, a fuel injection valve, and a piston. The piston has a cavity recessed so as to be capable of receiving fuel injected from the fuel injection valve when the piston is positioned at a top dead center, and a notch formed by recessing a part of a circumferential edge of an opening of the cavity radially outward. The notch inclines radially inward at an angle of 0 to 50 relative to a center axis of the cylinder from a piston crown surface toward an inner circumferential wall surface.

A piston for an internal combustion engine including a piston crown and a combustion chamber recess recessed therein, the combustion chamber recess including a recess edge. The piston may also include a ring groove for receiving a piston ring. The piston may further include a cooling duct having a smaller spacing from the piston crown than that of a flank of the ring groove, the cooling duct defining a minimum spacing from the piston crown at a first location, and a minimum spacing from the combustion chamber recess at a second location. The cooling duct may have a rounded portion between the first location and the second location. The cooling duct may have a maximum spacing from the recess edge at a third location. The rounded portion may have a rounding radius defined at least at the third location that is greater than 4% of a piston diameter.