A method of operating an internal combustion engine having at least one combustion chamber and an actuator disposed therein being arranged to drive an output shaft of the engine, the method comprising: 5 (i) injecting a water containing fuel into the combustion chamber, (ii) flash boiling the water-containing fuel to form water vapour within the combustion chamber, (iii) thermolyzing the water vapour to form hydrogen gas and oxygen gas; and (iv) combusting the hydrogen gas to drive the actuator within the combustion chamber to 10 thereby drive the connected output shaft of the combustion engine.

A diesel engine system is provided, which includes a piston having a cavity dented downwardly in a crown surface thereof and having a bottom part, a peripheral part dented so as to be convex radially outward, and a lip part formed above the peripheral part and protruding so as to be convex radially inward in a cross-sectional view. An injection controller causes an injector to perform, during operation in a given operating range, a main injection in which injected fuel is directed to the lip part, and an after-injection in which a smaller amount of the fuel than the main injection is injected at a given timing later than the main injection in an expansion stroke. An injection interval period from an end of the main injection to a start of the after-injection is shorter as a temperature parameter related to a progress of a warmup of engine increases.

A diesel engine system has a piston in which a cavity is formed in a crown surface. The cavity has a bottom part, a peripheral part dented so as to be convex radially outward in a cross-sectional view, and a lip part formed above the peripheral part and protruding so as to be convex radially inward in the cross-sectional view. An injection controller causes an injector to perform, during operation in a given operating range, a main injection in which injected fuel is directed to the lip part, and an after-injection in which a smaller amount of fuel than the main injection is injected at a given period later than the main injection in an expansion stroke. An injection interval period that is a period of time from an end of the main injection to a start of the after-injection is shorter as an injection pressure of fuel increases.

A fuel system for an internal combustion engine includes a fuel injector having a nozzle with first and second sets of spray orifices formed therein. The fuel injector also includes a first and a second outlet check movable to open and close the first and second sets of spray orifices. Spray plume ducts are supported at fixed orientations relative to a nozzle of the fuel injector, and each are oriented in-line with a center axis defined by one of the spray orifices. The spray plume ducts may be directly attached to the fuel injector or to a duct carrier mounted to an engine head.

A control device for an engine is provided, which includes a combustion controlling module, and an ignition retard determining module configured to determine whether there is a request for an ignition retard for retarding an ignition timing of an ignition plug. When the controlling module controls the ignition plug and an injector so that the SPCCI combustion is performed and there is not the ignition retard request, the controlling module executes a control in which the entire fuel to be injected in one cycle is injected in an intake stroke and a jump-spark ignition is carried out at a basic ignition timing, and when there is the ignition retard request, the controlling module executes a control in which an injection is performed in an intake stroke, a portion of the entire fuel is injected in a compression stroke, and the ignition timing is retarded from the basic ignition timing.

A fuel injector includes an injector body with a fuel chamber configured to receive fuel from a fuel line, an injector tip provided at an end of the injector body, and one or more nozzle assemblies provided in the injector tip. The one or more nozzle assemblies have a fuel channel in fluid communication with the fuel chamber, a premixing tube fluidly connected to the fuel channel, and a port fluidly connected to the premixing tube. The premixing tube has an orifice providing an outlet for the injector tip.

A fuel system for an internal combustion engine includes a fuel injector having a nozzle with first and second sets of spray orifices formed therein. The fuel injector also includes a first and a second outlet check movable to open and close the first and second sets of spray orifices. Spray plume ducts are supported at fixed orientations relative to a nozzle of the fuel injector, and each are oriented in-line with a center axis defined by one of the spray orifices. The spray plume ducts may be directly attached to the fuel injector or to a duct carrier mounted to an engine head.

In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the engine includes a lower cavity, an upper cavity, and a lip portion therebetween. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the load is lower than the load in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller sets the timing of the pilot injection(s) so that the distribution ratio of the fuel spray of the pilot injection(s) for the lower cavity is higher when the engine operates in the first state than when in the second state.

In a compression-ignition engine having a two-stage cavity, the distribution ratio between fuel for an upper cavity and fuel for a lower cavity is maintained even when the operational state of the engine changes. A piston of the engine includes a lower cavity, an upper cavity, and a lip portion between the lower cavity and the upper cavity. A controller causes a main injection and at least one pilot injection to be executed when the engine operates in a first state and a second state in which the load is lower than the load in the first state. The fuel spray is distributed to the lower cavity and the upper cavity. The controller outputs a control signal to a fuel injection valve so that a distribution ratio for the upper cavity is higher when the engine operates in the second state than when in the first state.

A first engine fuel, for example diesel fuel, is reformed (preferably via steam reforming) to produce syngas for use as a second engine fuel, with the fuels then both being used in an internal combustion engine to perform Reactivity Controlled Compression Ignition (RCCI). The syngas is produced and supplied to the engine as a supercritical fluid, thereby avoiding the pumping losses that would occur if syngas was pressurized for supply/injection. The reforming is done by a reformer which is provided as a unit with the engine (e.g., both the engine and reformer are onboard a vehicle), thereby effectively allowing use of a single fuel for RCCI engine operation.