A mixing structure can include a body having first conduits, mixture conduits, and second conduits extending through the body to the internal volume. The first conduits may be closer to a first side of the body than the mixture conduits and the second conduits. The second conduits may closer to another side of the body than the first conduits and the mixture conduits. The internal volume may receive liquid streams from an injector. The first conduits and the second conduits may receive gas streams from outside the body. The body may thermally modify the gas streams and entrain the gas streams into the liquid streams in the internal volume. The mixture conduits may be positioned to direct the gas streams entrained into the liquid streams out of the body in directions directed toward the second side of the body and away from the first side of the body.

A fuel and gas mixing structure for an engine is provided. This mixing structure includes a body configured to be positioned between a fuel injector and a cylinder of an engine. The body defines an interior volume that is configured to receive gas (e.g., air) from outside the body and to receive one or more streams of fuel from the fuel injector in the interior volume. The body also includes one or more upper channels and one or more lower channels that are configured to provide a substantially similar amount of flow relative to each other to the interior volume The body also defines one or more mixture conduits configured to conduct plumes of the fuel and gas, while mixing, from the interior volume to one or more exit ports and therethrough to the cylinder.

A piston includes a swirl pocket that extends radially from the radially outer lip portion to a lower axial extremity spaced away from the radially outer lip portion a first axial distance. A convex arcuate surface extends downwardly and inwardly from the radially outer lip portion, a concave arcuate surface extends to the lower axial extremity from the convex arcuate surface, and a conical portion extends upwardly and inwardly from the concave arcuate surface to an apex that is spaced a second axial distance from the radially outer lip portion that is less than the first axial distance.

Operating an engine includes injecting a first charge of liquid fuel using a first set of nozzle outlets in a fuel injector, and injecting a second charge of liquid fuel using a second set of nozzle outlets in a fuel injector. The first charge is autoignited in a first engine cycle, and the second charge is autoignited in a second engine cycle, and may be used to pilot ignite a charge of gaseous fuel. Operating the engine further includes limiting errors in targeting of the second charge of liquid fuel caused by transitioning the engine from a first combination to a second combination of speed, load, and boost, by varying an injection pressure of the liquid fuel from the first engine cycle to the second engine cycle.

This piston for a diesel engine includes: a bottom portion that has a deepest combustion chamber bottom in the combustion chamber; a circumferential protrusion that is provided around an entire circumference of a circumferential wall between the bottom portion and a top surface of the piston and protrudes toward an intersection (P0) of a center line of the piston and the top surface in a cross-sectional view that includes the center line; an inclination portion that inclines closer to the top surface toward an outer side in a radial direction from the circumferential protrusion; and a rising portion that rises from the inclination portion toward the top surface.

A fuel injector includes an injector housing having a fuel connector, and an outer housing surface extending around a longitudinal axis of the injector housing. The outer housing surface includes a cylindrical upper section, a cylindrical lower section, and a middle section. The fuel connector defines a connector axis oriented normal to a longitudinal axis of the injector housing and extending between a first connector end attached to the middle section, and a terminal connector end radially outward of the outer housing surface and having therein a fuel inlet. The fuel connector includes an outer connector surface having an unthreaded base section, and an externally threaded end section adjacent to the terminal connector end.

Operating an engine includes moving a piston in a combustion chamber between a bottom dead center position and a top dead center position in an engine cycle. A fuel is injected into the combustion chamber through a plurality of sets of nozzle outlets varied set-to-set with respect to outlet size and spray angle. Spray jets of the injected fuel are propagated in an impingement-limiting fuel spray pattern that is based on the set-to-set variation in outlet size and spray angle so as to limit dissipation of heat from combustion of the injected fuel to material of the engine by way of a thermal barrier coating (TBC) upon a surface of the combustion chamber.

An internal combustion engine includes a piston and a fuel injection valve. The fuel injection valve includes a first injection hole, a second injection hole, a first needle configured to open and close the first injection hole, and a second needle configured to open and close the second injection hole. The first injection hole and the second injection hole are configured such that a portion of a fuel spray injected from the first injection hole and a portion of a fuel spray injected from the second injection hole overlap each other at a position apart at a predetermined distance from a side wall of a cavity of the piston. The second needle is configured to start operation in order to open the second injection hole after a predetermined time has elapsed from a point of time when the first needle starts operation in order to open the first injection hole.

A fuel injection valve has first injection holes, second injection holes, a first needle that opens and closes the first injection holes, and a second needle. The fuel injection valve is arranged such that a part of fuel injected from the first injection hole and a part of fuel injected from the second injection hole are gathered together at a position spaced from the side wall of the cavity by a predetermined distance. The second needle starts operating to open the second injection holes, after a predetermined time elapses from a point in time at which the first needle starts operating to open the first injection holes.

A piston for an internal combustion engine and method of construction thereof are provided. The piston includes an upper crown formed at least in part by a first metal material and a thermally insulating insert. The upper crown has an upper wall forming an upper combustion surface and a ring belt region. The upper combustion surface is formed at least in part by the thermally insulating insert. The thermally insulating insert has a base surface with pores extending upwardly therein. The first metal material is infused and solidified in the pores, with the first metal material forming a first bonding surface. The piston further includes a body portion formed from a second metal material. The body portion provides pin bosses having coaxially aligned pin bores and diametrically opposite skirt portions. The body portion has a second bonding surface bonded to the first bonding surface of the first metal material.