An engine system is provided, which includes a vehicle-mounted engine having an injector, a spark plug, an intake valve operating mechanism, and an exhaust valve operating mechanism, an accelerator opening sensor, and a controller. The engine is configured to execute flame propagation combustion and compressed self-ignition combustion. The controller performs a combustion control so that a target torque set based on an accelerator opening is realized in a specific cycle in the future from a present time by a given delay time. The controller sets beforehand the combustion mode based on a target load, estimates an in-cylinder property when the intake valve is closed in the present cycle, sets a target in-cylinder property so that the set combustion mode is realized in the specific cycle, and sets a target operating amount of each of the intake and exhaust valve operating mechanisms based on the set target in-cylinder property.

A split cycle internal combustion engine includes a combustion cylinder accommodating a combustion piston and a compression cylinder accommodating a compression piston. The engine also includes a controller arranged to receive an indication of a parameter associated with the combustion cylinder and/or a fluid associated therewith and to control an exhaust valve of the combustion cylinder in dependence on the indicated parameter to cause the exhaust valve to close during the return stroke of the combustion piston, before the combustion piston has reached its top dead centre position (TDC), when the indicated parameter is less than a target value for the parameter; and close on completion of the return stroke of the combustion piston, as the combustion piston reaches its top dead centre position (TDC), when the indicated parameter is equal to or greater than the target value for the parameter.

A system includes a fuel tank and a dehydration reactor that are configured to provide a primary fuel and a pilot fuel to a power system. The fuel tank is configured to store the primary fuel and is fluidly connected to a reactor feed line and a primary fuel line provide the primary fuel. The dehydration reactor is configured to receive the primary fuel via the reactor feed line and convert a portion of the primary fuel to the pilot fuel and a byproduct. The power system is configured to receive the pilot fuel from the dehydration reactor to initiate combustion of the primary fuel. The power system also includes a cylinder with an internal piston that receives the pilot fuel and the primary fuel, contains the combustion reaction, and generates power from the combustion reaction; and contains the combustion reaction. A pilot fuel injector provides the pilot fuel to the cylinder at a first time to initiate combustion and a primary fuel injector provides the pilot fuel to the cylinder at to generate power via the power system.

A dual fuel system includes a liquid pilot fuel supply, a liquid main fuel supply, and a fuel injection apparatus. The dual fuel system further includes a fueling control unit coupled with a cylinder pressure sensor and a NOx sensor, and structured to vary, via outputting a fueling control command to a main fuel injection control valve, fuel delivery parameters each on the basis of at least one of a cylinder pressure parameter or a NOx parameter. The fueling control unit compensates via the varying fuel delivery parameters for a change to a liquid main fuel composition such as a change from a first alcohol fuel or blend to a second alcohol fuel or blend.

A method for carrying out the operation of an internal combustion engine, wherein liquid fuel injection amounts are injected at cylinders of a group of cylinders of the internal combustion engine in the context of injection events, wherein in a first step, a first cylinder of the group with the strongest knocking tendency over a time period is determined, and in a second step an injection correction occurs such that the injection events at the first determined cylinder can be sequentially reduced in their injection duration or injection amount by a first correction value, while the injection duration or injection amount of the injection events at the other cylinders of the group are sequentially increased by a second correction value.

A knocking control method in a power generation system (1) which includes a gas engine (20) including a plurality of air cylinders (21) and a knocking detection unit (51) configured to detect knocking in each of the air cylinders (21). The knocking control method includes a first control step of delaying an ignition timing for at least one of the air cylinders (21) when the knocking detection unit (51) has detected knocking; a second control step of reducing an amount of gas supplied to at least one of the air cylinders (21) when the knocking has not been eliminated by the first control step; and a third control step of shutting off supply of a gas to any of the air cylinders (21) in which the knocking has occurred.

A variety of methods and arrangements for detecting misfire and other engine-related errors are described. In one aspect, a window is assigned to a target firing opportunity for a target working chamber. There is an attempt to fire a target working chamber during the target firing opportunity. A change in an engine parameter (e.g., crankshaft angular acceleration) is measured during the window. A model (e.g., a pressure model) is used to help determine an expected change in the engine parameter during the target firing opportunity. Based on a comparison of the expected change and the measured change in the engine parameter, a determination is made as to whether an engine error (e.g., misfire) has occurred.

A control device for an internal combustion engine is configured to carry out a lean combustion of which excess air factor is 2.0 or more by injecting fuel for creating a homogeneous air-fuel mixture from a first fuel injection valve into a combustion chamber of an engine main body, injecting ignition fuel for creating an ignition air-fuel mixture near an electrode portion of a spark plug from a second fuel injection valve, and igniting the ignition air-fuel mixture, and when occurrence of knocking is detected based on a detection value of a knock sensor during the lean combustion, apply retard correction to each of an ignition timing of the spark plug and an injection timing of the ignition fuel set corresponding to an engine operating state, and apply increase correction to an injection amount of the ignition fuel.

Emission targets, such as NOx levels, for gaseous fuelled internal combustion engines that burn a gaseous fuel in a diffusion combustion mode are increasingly more challenging to achieve. A method of fuel injection for an internal combustion engine fuelled with a gaseous fuel comprises introducing a first amount of pilot fuel in a first stage of fuel injection; introducing a first amount of main fuel (the gaseous fuel) in a second stage of fuel injection; and introducing a second amount of main fuel in a third stage of fuel injection. The first and second amounts of main fuel contribute to load and speed demand of the internal combustion engine. Engine maps calibrated for different engine performance can be employed in different regions of the load and speed range of the engine. The engine maps are blended when the engine transitions between two regions; and momentary excursions into different regions do not change the engine calibration.

A process to adjust the ignition timing of an air-fuel mixture in a combustion chamber of an internal combustion engine, the process comprises determining a first quantity indicative of a pressure of the mixture for a cycle of the engine, determining a second quantity indicative of a speed of the engine, determining a third quantity indicative of a first temperature of a conditioning fluid, providing a heat exchange mathematical model for the combustion chamber, which maps the three quantities from the first to the third one onto a fourth quantity indicative of a second temperature of a wall portion around the combustion chamber, estimating the fourth quantity by means of the three determined quantities and by means of the mathematical model, and adjusting the ignition timing as a function of the fourth estimated quantity.