The deterioration of combustion due to condensed water flowing into a cylinder is suppressed as much as possible. A control apparatus for an internal combustion engine is applied to an internal combustion engine which includes a fuel injection valve that directly injects fuel into a cylinder and a spark plug. The internal combustion engine is constructed so that the fuel goes to the spark plug. The control apparatus comprising a controller configured to: predict whether condensed water flows into the cylinder during an intake stroke; and carry out first injection control to perform fuel injection in a predetermined period of time within a period of time which is after closure of an exhaust valve and before the condensed water flows into the cylinder, and second injection control to perform fuel injection in a compression stroke before ignition, if an inflow of the condensed water into the cylinder is predicted.

Methods and systems are provided for performing an onboard cylinder leakdown test in response to an indication of cylinder misfire. In one example, following an engine-off event and an engine temperature above a threshold, fuel is injected into the indicated cylinder under conditions wherein the cylinder is expected to be sealed, and the detection of hydrocarbon migration out of the cylinder indicates cylinder degradation. In this way, cylinder degradation may be accurately diagnosed without intrusive, time consuming, and difficult off-board cylinder leakdown tests.

A nozzle hole of a nozzle plate is coupled to a fuel injection port of a fuel injection device via a swirl chamber and first and second fuel guide channels opened into the swirl chamber. The swirl chamber is formed by combining first and second elliptical-shaped recessed portions. The first fuel guide channel opens at a side of a short axis of the first elliptical-shaped recessed portion and a side of the short axis that does not overlap with the second elliptical-shaped recessed portion, and the second fuel guide channel opens at a side of a short axis of the second elliptical-shaped recessed portion and a side of the short axis that does not overlap with the first elliptical-shaped recessed portion. The first and second fuel guide channels have depths deeper than those of the swirl chamber and extend inside of the swirl chamber while gradually reducing cross-sectional areas.

A combustion system is provided for an internal combustion engine including a cylinder head and a piston. In one example, a combustion system may include a cylinder head with a second cylinder surface angled relative to a first cylinder surface, an intake port coupled to the first cylinder surface, an exhaust port coupled to the second cylinder surface, and a piston with a first piston surface parallel to the first cylinder surface and a second piston surface parallel to the second cylinder surface.

A method is disclosed for injecting a gaseous fuel in an internal combustion engine having a combustion chamber and an inlet valve assigned to the combustion chamber. The method includes determining a torque output of the combustion chamber, specifying a comparative value for the torque output, and determining a difference between the torque output and the comparative value. When the difference is less than a given threshold value, the method reduces a first injection quantity of the gaseous fuel depending on the determined difference, which is injected temporally before the inlet valve is closed. When the difference is greater than the given threshold value, the method increases the first injection quantity of the gaseous fuel depending on the determined difference. Also described is a device which may carry out the method.

An ignition chamber of a combustion engine, the ignition chamber comprising: a piston having a piston bottom surface and a cylinder head having a cylinder head surface, the ignition chamber having an ignition chamber axis wherein one of said piston bottom surface and said cylinder head surface includes at least one depression and an ignition device is disposed in said ignition chamber and extends along said ignition chamber axis, said ignition device is configured to cause a cylindrical ignition impulse along said ignition chamber axis so as to create radial impulse components that are redirected by said depression so as to move in a direction longitudinal to said combustion chamber axis.

Among all combinations of two injection holes, in a combination in which when the injection holes are offset such that their central axes are coincident with each other in inlet openings, an inter-injection hole angle formed by the central axes is minimized, the inter-injection hole angle between the two injection holes is represented as amin[deg], taper angles, which are formed by the respective contours of the injection hole inner walls in the cross sections along the virtual planes including the central axes of the two injection holes that allow the inter-injection hole angle to be minimized, are represented as a1 and a2[deg], and when fuel is injected from the injection holes, average pressure of the fuel in the fuel passage is represented as P[Mpa], and the injection holes are formed so as to satisfy a relationship: amina1+a2+0.5P.sup.0.6

A cylinder head includes: a cylinder head body; multiple fuel ports extending to cylinders from a sidewall surface of the cylinder head body, the sidewall surface being located on one side of a longitudinal axis, on which intake ports are disposed; multiple injection valve attachment bosses projecting from the sidewall surface, surrounding openings of the fuel ports, and adapted to attach cylinder fuel injection valves to the fuel ports; and multiple projections projecting from the sidewall surface and disposed adjacent to the corresponding injection valve attachment bosses. A cylinder block includes: a cylinder block body; and a sensor attachment boss projecting from a sidewall surface of the cylinder block body, the sidewall surface being located on the one side of the longitudinal axis, on which the sidewall surface of the cylinder head body is located. The sensor attachment boss is adapted to attach a knock sensor to the cylinder block.

Provided is an internal combustion engine including a sparkplug disposed in the vicinity of the center portion of an upper wall surface of a combustion chamber. Tumble flow generated during lean burn operation is controlled such that the tumble flow shape changes according to the engine rotation speed between a first tumble shape (usual tumble shape) in which the flow direction of a gas around the sparkplug at the time of ignition is direction from an intake valve side toward an exhaust valve side in a latter half of a compression stroke, and a second tumble shape ( tumble shape) in which the flow direction of the gas is reversed in the latter half of the compression stroke from the direction from the intake valve side toward the exhaust valve side to the direction from the exhaust valve side toward the intake valve side.

An engine controller controls a direct fuel-injection, spark ignition engine including a fuel injection valve configured to directly inject a fuel into a cylinder, and an ignition plug that spark-ignites a mixture in the cylinder. The engine controller is provided with an acceleration request sensor configured to detect an acceleration request of a driver, and when the acceleration request occurs and a top surface temperature of a piston in the cylinder is lower than a predetermined temperature, the engine controller retards an ignition timing so that a period of time until a flame after the ignition reaches the piston top surface is extended.