A method of controlling combustion in an internal combustion engine includes measuring parameters of combustion in a cylinder of the engine during a combustion phase of the cylinder, after igniting an air/fuel charge in the cylinder, and calculating the heat release of combustion in the cylinder based on the measured parameters. An auto-ignition event of the air/fuel charge is identified based on the calculated heat release, and, based at least in part on the identified auto-ignition event, at least one of ignition timing in the cylinder for the next combustion phase of the cylinder or an amount of exhaust gas supplied to the cylinder for the next combustion phase of the cylinder is controlled to cause an auto-ignition event of the air/fuel charge in the next combustion phase to shift toward a specified crank angle.

A combustion control system for a dual fuel engine includes a combustion control unit structured to receive phasing data for combustion of a main charge of gaseous fuel ignited by way of pilot shots of a liquid fuel, output a pilot fueling command based on the phasing data, and output a valve timing command. The combustion control unit is further structured to vary a phasing of combustion of a main charge of a gaseous fuel ignited by pilot shots of a liquid fuel based on an adjustment to at least one of a pilot shot delivery parameter or a valve timing parameter such as intake valve closing timing from a first engine cycle to a second engine cycle. Control of the intake valve timing can be based on a main pilot shot timing error.

To provide a controller and a control method for an internal combustion engine capable of performing automatic adaptation of the optimal ignition timing or the optimal control value of the combustion operation mechanism during operating. A controller and a control method for an internal combustion engine changes setting values of a torque characteristics function so that an output torque calculated using the torque characteristics function approaches an output torque calculated based on an actual value of internal cylinder pressure; calculates a plurality of output torques corresponding to respective plurality of combustion control states using the torque characteristics function; and changes setting values of a combustion control target setting function so that a target value of combustion control state calculated using the combustion control target setting function approaches a maximum torque combustion control state where the output torque becomes the maximum.

An estimation device is applicable to a combustion system including an internal combustion engine. The estimation device includes a mixing acquisition unit, a combustion amount estimation unit, and a region estimation unit. The mixing acquisition unit acquires the mixing ratio of various components contained in the fuel used for combustion in the internal combustion engine. The combustion amount estimation unit estimates a main combustion amount of the fuel caused by a main combustion produced by injecting the fuel into a combustion chamber of the internal combustion engine with a main injection, based on the mixing ratio acquired by the mixing acquisition unit. The region estimation unit estimates a combustion region of the main combustion in the combustion chamber based on the mixing ratio acquired by the mixing acquisition unit.

A control device for a compression ignition engine is provided, which causes an injector to perform a pre-injection and a main injection, sets fuel injection timings of these injections so that an interval between a first peak of a heat release rate resulting from the combustion of fuel injected by the pre-injection and a second peak of the heat release rate resulting from the combustion of fuel injected by the main injection becomes an interval to make pressure waves caused by these combustions cancel each other out, and when an increase of an oxygen concentration of intake air supplied to a combustion chamber is detected, controls the injector to reduce the injection amount and retard the injection timing of the pre-injection compared with a case where the concentration increase is not detected under a condition that engine load and speed are the same.

A control system for a compression-ignition engine includes a combustion chamber, an injector, an ignition plug, a sensor device, and a controller having a circuitry. The ignition plug forcibly ignites mixture gas to start combustion accompanied by flame propagation of a part of the mixture gas, and again ignites remaining unburnt mixture gas at a timing at which the unburnt mixture gas combusts by self-ignition. The controller is configured to execute an ignition controlling module to output an ignition signal to the ignition plug before a target timing so that the unburnt mixture gas self-ignites at the target timing, an ignition timing estimating module to estimate an actual CI timing indicative of a timing at which the unburnt mixture gas actually self-ignited based on an in-cylinder pressure parameter, and an in-cylinder temperature determining module to determine the in-cylinder temperature at a given crank angle based on the estimated result.

An aircraft diesel engine may be operated at a minimal fuel rate. Shaft output power of the engine may be reduced by initiating combustion during the compression stroke. Combustion may be initiated during the compression stroke by advancing fuel injection, splitting fuel injection, and/or manipulating individual injection quantities. Initiating combustion during the compression stroke may slew torque generation to the compression stroke.

A control device for controlling an engine including an injector that supplies fuel into a cylinder and an in-cylinder pressure sensor that detects an in-cylinder pressure being a pressure inside the cylinder, is provided. The device includes a processor configured to execute an abnormal combustion determining module to determine whether combustion of a mixture gas inside the cylinder is abnormal based on a detection value of the in-cylinder pressure sensor. The abnormal combustion determining module determines that an abnormal combustion has occurred in which progress of the combustion of the mixture gas is excessively fast, when an in-cylinder pressure intensity that is a spectrum value of a frequency component of an in-cylinder pressure waveform less than a given reference frequency is greater than or equal to a given determination intensity, the in-cylinder pressure waveform being detected by the in-cylinder pressure sensor.

A control system for controlling pilot fuel injection in a dual fuel engine is disclosed. The control system may determine, using measurements from one or more sensors, one or more combustion parameters associated with the dual fuel engine during operation of the dual fuel engine. The control system may determine an estimated nitrogen oxides (NOx) emissions level based on the one or more combustion parameters, and may determine a NOx error based on a comparison between the estimated NOx emissions level and a desired NOx emissions level. The control system may control a quantity of pilot fuel injected into the dual fuel engine based on the NOx error.

An aircraft diesel engine may be operated at a minimal fuel rate. Shaft output power of the engine may be reduced by initiating combustion during the compression stroke. Combustion may be initiated during the compression stroke by advancing fuel injection, splitting fuel injection, and/or manipulating individual injection quantities. Initiating combustion during the compression stroke may slew torque generation to the compression stroke.