Combustion stability can be improved while HC and PN discharged from a combustion chamber are prevented. In an ECU that controls a fuel injection device installed in a combustion chamber of an internal-combustion engine so as to be able to inject fuel in a direction intersecting with a sliding direction of a piston, a pressure value of the fuel supplied to the fuel injection device is acquired, control is performed such that the fuel injection device injects the fuel at least twice in a compression stroke, and control is performed such that fuel injection timing of at least one time in the compression stroke is advanced earlier than fuel injection timing of a time corresponding to the high pressure value of the fuel when the acquired fuel pressure value is low.

A method for operating an internal combustion engine includes moving a piston downward from a top dead center position to a bottom dead center position expanding a combustion chamber in an intake stroke, dispensing a first portion of fuel into the combustion chamber, subsequent to moving the piston downward in the intake stroke, moving the piston upward in the vertical direction compressing the combustion chamber in a compression stroke, subsequent to moving the piston upward in the compression stroke, moving the piston downward in the vertical direction in an expansion stroke, while moving the piston downward in the vertical direction in the expansion stroke, dispensing a second portion of fuel into the combustion chamber, and while moving the piston downward in the expansion stroke, igniting at least a part of the first portion of fuel and the second portion of fuel.

Various embodiments of the present disclosure are directed to methods of operating a spark-ignition internal combustion engine. In one embodiment, a method is disclosed including fuel is injected centrally into a combustion chamber via at least one fuel injection device per cylinder in at least one operating range of the internal combustion engine and is ignited centrally in the combustion chamber via at least one ignition device. The fuel is injected into the combustion chamber at an injection pressure of over 500 bar in the second half of the compression stroke before the top dead center of combustion and the internal combustion engine is operated at an air-fuel ratio 1.

In at least one operating range of the internal combustion engine, the fuel is injected into the combustion chamber between 180 and 0 before the top dead center.

An internal combustion engine (1) is provided with a turbocharger (2), and is configured to be switchable between a stoichiometric combustion mode having a theoretical air-fuel ratio as a target air-fuel ratio and a lean combustion mode having a lean air-fuel ratio as a target air-fuel ratio. An air bypass valve (20) is provided in an air bypass passage (19) communicating a collector (11a) on the downstream of a throttle valve (12) with the upstream side of a compressor (2b) in an intake passage (11). At the time of the shifting from the lean combustion mode to the stoichiometric mode, the throttle valve (12) is closed and the air bypass valve (20) is temporarily opened to decrease the pressure inside the collector (11a) quickly.

A control device of an engine including a cylinder, a piston, a cylinder head, and a combustion chamber is provided, which includes intake and exhaust ports, a swirl control valve provided in an intake passage connected to the intake port, a fuel injection valve attached to the cylinder head to be oriented into the center of the combustion chamber in a plan view thereof, and having first and second nozzle ports, and a control unit. The control unit includes a processor configured to execute a swirl opening controlling module to output the control signal to the swirl control valve to have a given opening at which a swirl ratio inside the combustion chamber becomes 2 or above, and a fuel injection timing controlling module to output the control signal to the fuel injector to inject fuel at a given timing at which the swirl ratio becomes 2 or above.

A control method of an internal combustion engine including a spark plug and a fuel injection valve includes starting electric discharge of the spark plug after a gas flow in a direction from a side of the fuel injection valve toward a side of the spark plug is generated at a position of an electric discharge gap of the spark plug due to spray of the fuel injected from the fuel injection valve.

A control method for an internal combustion engine including a variable compression ratio mechanism which includes: implementing a compression ratio fixing control in which a mechanical compression ratio is fixed to a predetermined low compression ratio, and controlling combustion form in a cylinder to stratified combustion, under engine idling during catalyst warming-up; controlling the combustion form in the cylinder to homogeneous combustion, under an operation state other than the engine idling during the catalyst warming-up; and implementing the compression ratio fixing control and controlling the combustion form in the cylinder to the homogeneous combustion, in response to pressing-down of an accelerator under the engine idling during the catalyst warming-up, and as long as the engine idling during the catalyst warming-up has a possibility to resume in response to release of the accelerator after the pressing-down.

A cylinder deactivation change apparatus including fuel supply parts supplying fuel into a first and second combustion chambers of a first and second cylinders, ignition parts igniting fuel-air mixture in the first and the second combustion chambers and a microprocessor. The microprocessor is configured to perform determining whether changing the operation mode is necessary, and controlling the fuel supply parts and ignition parts so as to ignite at first ignition timing before it is determined that changing the operation mode to the first mode is necessary, and so as to ignite at second ignition timing retarded in comparison with the first ignition timing and so as to supply the fuel into the first combustion chamber in a manner that causes a stratified charge combustion in the first combustion chamber, when it is determined that changing the operation mode to the first mode is necessary.

A split cycle internal combustion engine comprising a compression cylinder accommodating a compression piston; a combustion cylinder accommodating a combustion piston; a crossover passage between the compression cylinder and the combustion cylinder arranged to provide working fluid to the combustion cylinder; a controller arranged to determine a peak temperature of combustion in the combustion cylinder based on a received indication of a peak temperature of combustion in the combustion cylinder; and a coolant system arranged to regulate a temperature of the working fluid supplied to the combustion cylinder; wherein, in response to determining that the peak temperature of combustion exceeds a selected threshold, the controller is configured to control the coolant system to regulate the temperature of the working fluid supplied to the combustion cylinder so that a peak temperature of combustion in the combustion cylinder is less than the selected threshold.

A fuel injection control device for an engine is provided. A swirl generator generates a swirl flow inside a combustion chamber. A fuel injector with multiple nozzle holes injects fuel into the combustion chamber, and forms a lean mixture gas inside the combustion chamber. An spark plug ignites the lean mixture gas to cause a portion of the mixture gas to start combustion accompanied by flame propagation, and then combusts by self-ignition. The fuel injector has first and second nozzle holes, and a first atomized fuel spray injected from the first nozzle hole and a second atomized fuel spray injected from the second nozzle hole separate from each other by the swirl flow. The fuel injector sequentially performs a first injection and a second injection in an intake stroke. The controller makes an injection amount of the second injection greater than that of the first injection.