A piston for use in a GDCI engine cooperates with the wall of a cylinder defined in the engine and with a cylinder head to define a combustion chamber. The surface of the piston that faces the cylinder head defines a bowl that is configured to receive fuel that is dispensed from a fuel injector that is located in the cylinder head substantially along the central axis of the cylinder. The bowl is configured such that substantially all of the injected fuel associated with a combustion event reaches a localized equivalence ratio greater than 0.0 and less than or equal to 1.2 at a time immediately preceding initiation of the combustion event.

An injector (1) for injecting fuel and an additional fluid, is provided in that the injector (1) is designed for optimal space-saving yet exhibiting a simple construction. This construction results in a precise injection of a fuel and an additional fluid into a combustion chamber of an internal combustion engine. The arrangement has two solenoid valves, the first valve (2) and the second valve (3). The second solenoid valve (3) has a second nozzle needle (9) which is arranged in the injector (1), and the first nozzle needle (7) of the first solenoid valve (2) and the second nozzle needle (9) of the second solenoid valve (3) are arranged one behind the other on a longitudinal axis (10) of the injector (1). Further, the nozzle needles (7, 9) can be controlled independently of one another.

A method to control the combustion of a compression ignition engine having the steps of: establishing, for each combustion cycle, a fuel quantity to be injected into the cylinder; injecting a first fraction of the fuel quantity; heating a second fraction of the fuel quantity, which is equal to the remaining fraction of the fuel quantity, to an injection temperature higher than 100° C.; injecting the second fraction of the fuel quantity heated to the injection temperature into the cylinder at the end of the compression stroke and at no more than 60° from the top dead centre; and decreasing the injection temperature and the ratio between the second fraction and the first fraction as the internal combustion engine increases and as the rotation speed of the internal combustion engine increases.

A controller for an internal combustion engine is configured to execute: a process of switching the injection mode according to an engine operational state; an anomaly determination process of determining whether there is an anomaly in the injection system that is implementing a single injection mode during implementation of the single injection mode; a provisional determination process of provisionally determining whether there may be an anomaly in the injection system that is implementing the single injection mode during the implementation of the single injection mode; and an idle determination process of, if it is determined that there is an anomaly in the provisional determination process, prohibiting the automatic stop and executing, during an idle operation, the anomaly determination process by implementing an injection mode that uses only the injection system provisionally determined to have an anomaly in the provisional determination process.

Fuel management system for enhanced operation of a spark ignition gasoline engine. Injectors inject an anti-knock agent such as ethanol directly into a cylinder. It is preferred that the direct injection occur after the inlet valve is closed. It is also preferred that stoichiometric operation with a three way catalyst be used to minimize emissions. In addition, it is also preferred that the anti-knock agents have a heat of vaporization per unit of combustion energy that is at least three times that of gasoline.

A fuel injection device is provided with reduced adherence of fuel spray with respect to an intake valve, a wall surface in an engine cylinder, or a piston. The fuel injection device includes a valve body and a seat surface to perform sealing of fuel cooperatively and injection holes. Inlet opening surfaces are formed on the seat surface. A first injection hole and a second injection hole arranged closest to the first injection hole. The first injection hole is larger than the second injection hole in an injection hole angle to be an angle formed by a normal direction of the seat surface and a center axis of the injection hole. The second injection hole is larger than the first injection hole in an area of a cross-section perpendicular to the center axis of the injection hole.

Control is performed so as to occur SPCCI combustion in which, after an air-fuel mixture in a first area of a combustion chamber that includes an electrode portion of an ignition device is burned by receiving ignition energy, an air-fuel mixture formed in a second area located on an outer periphery of the first area is self-ignited. Control is also performed such that, in a high load operation region of an SPCCI combustion execution region, an air-fuel ratio in the entire combustion chamber becomes richer than a stoichiometric air-fuel ratio and that an air-fuel ratio of the air-fuel mixture in the first area becomes leaner than an air-fuel ratio of the air-fuel mixture in the second area.

The invention relates to an internal combustion engine and to a method for operating the internal combustion engine, which has at least one cylinder having a combustion chamber, the combustion chamber being bounded by a cylinder roof, a cylinder wall and a movable cylinder piston, a multi-hole injection nozzle and a spark plug being arranged in a central position in the cylinder roof, the multi-hole injection nozzle injecting fuel into the combustion chamber at injection pressures of >/=300 bar by means of a plurality of injection jets. It is provided that at least one injection jet (i>/=1) injects fuel into a three-dimensional space within the combustion chamber on the intake side, which space lies below an opening of at least one intake valve (104A, 104B) with respect to the direction of the longitudinal central axis (Z) of the cylinder, and at least four injections jets (i>/=4) inject fuel into a three-dimensional space of the combustion chamber on the exhaust side, which space lies below an opening of at least one exhaust valve (105A, 105B).

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.

In an internal combustion engine which performs a homogeneous lean combustion mode and a stratified lean combustion mode, there is provided a new internal combustion engine control device capable of obtaining a stable combustion state by decreasing influences of delay of an air flow and a degree of change of a transient state and smoothly performing switching between the homogeneous lean combustion mode and the stratified lean combustion mode. Accordingly, in the present invention, when switching between the stratified lean mode in which a compression stroke injection is performed by a direct injection injector 7 and the homogeneous lean combustion mode in which an intake stroke injection is performed by the direct injection injector 7 is performed, a predetermined delay time t is provided from at least a switching operation of a tumble control valve 6, a switching operation between the compression stroke injection and the intake stroke injection is performed, and the delay time t is set so as to correspond to a magnitude of the degree of change L of the transient state. A switching timing between the compression stroke injection and the intake stroke injection is controlled according to the flow delay of an air control system such as the tumble control valve 6 and the degree of change L of the transient state, and thus, it is possible to improve combustion stability in a combustion chamber.