An engine system comprising an internal combustion engine and a turbocharger, where a diameter of the at least one intake valve is greater than a diameter of the at least one exhaust valve, the salient angle of the piston bowl is at least 10 degrees, the ratio between the piston bowl opening diameter and the piston bowl depth is approximately 0.5 to 2.0, the intake valve opens before top dead center on an exhaust stroke of the internal combustion engine and closes before bottom dead center of an intake stroke of the internal combustion engine, and the turbocharger has a combined efficiency of more than 50%.

An internal combustion engine includes a fuel injection nozzle provided with a nozzle hole for injecting fuel, the nozzle hole exposed from a cylinder head of the internal combustion engine to a combustion chamber, and a hollow duct, an inlet and an outlet of which are exposed to the combustion chamber. The duct is provided in a manner allowing fuel spray injected from the nozzle hole of the fuel injection nozzle to pass through from the inlet to the outlet. The fuel injection nozzle and the duct are configured such that a part of fuel spray that is injected in pilot injection that is performed before main injection directly adheres to an inner wall surface of the duct.

An internal combustion engine includes a fuel injection nozzle provided with a nozzle hole for injecting fuel, the nozzle hole exposed from a cylinder head of the internal combustion engine to a combustion chamber, and a hollow duct, an inlet and an outlet of which are exposed to the combustion chamber. The duct is provided in a manner allowing fuel spray injected from the nozzle hole of the fuel injection nozzle to pass through from the inlet to the outlet. The fuel injection nozzle and the duct are configured such that a part of fuel spray that is injected in pilot injection that is performed before main injection directly adheres to an inner wall surface of the duct.

A reciprocating-piston machine, in particular an internal combustion engine with a variable compression ratio, having a length adjustment device arranged in a connecting rod and can be activated by way of a switching unit arranged in the connecting rod, wherein an actuating mechanism is operatively connected to the switching unit in the region of a connecting rod bearing in order to introduce a switching pulse into the connecting rod. The actuating mechanism has a transmission means arranged in the region of the connecting rod bearing, and the switching unit has at least one switching valve which is arranged in the connecting rod body of the connecting rod and the valve body, which can be displaced substantially in the direction of the rotational axis of the connecting rod bearing, and can be deflected out of a dosed position into an open position by way of the transmission means.

A reciprocating-piston machine, in particular an internal combustion engine with a variable compression ratio, having a length adjustment device arranged in a connecting rod and can be activated by way of a switching unit arranged in the connecting rod, wherein an actuating mechanism is operatively connected to the switching unit in the region of a connecting rod bearing in order to introduce a switching pulse into the connecting rod. The actuating mechanism has a transmission means arranged in the region of the connecting rod bearing, and the switching unit has at least one switching valve which is arranged in the connecting rod body of the connecting rod and the valve body, which can be displaced substantially in the direction of the rotational axis of the connecting rod bearing, and can be deflected out of a dosed position into an open position by way of the transmission means.

Internal combustion engine apparatuses, systems and methods. The internal combustion engine system includes a cylinder block including a cylinder bore and a piston movably positioned in the cylinder bore. The piston is configured to slide in an axial direction within the cylinder bore. The piston includes a piston crown and a turbulence induction protuberance extending in an axial direction from the piston crown. The turbulence induction protuberance is positioned radially intermediate an axial center of the piston and a circumferential portion of the piston. The turbulence induction protuberance is configured to cause turbulence in a propagating flame propagating from a central region of the cylinder bore to cause the propagating flame to extend to a circumferential portion of the cylinder bore.

A compression ignition engine includes: a naphtha injector for supplying naphtha to a combustion chamber; a diesel fuel injector for supplying diesel fuel having a higher boiling point than naphtha; an ignition device for assisting ignition of an air-fuel mixture; and a PCM connected to the naphtha injector, the diesel fuel injector, and the ignition device. When the diesel engine is cold, the PCM supplies only naphtha out of naphtha and diesel fuel, and assists ignition of an air-fuel mixture formed by naphtha.

When the geometric compression ratio of an engine body is set to 13:1 or more and the engine body operates in a preset high load region, the effective compression ratio of the engine body is set to 12:1 or more with a difference from the geometric compression ratio being within 2, a gas to be introduced into a combustion chamber is supercharged by a supercharging system, fuel is injected at least in a compression stroke by an injector, and after the fuel injection is finished, an air-fuel mixture in the combustion chamber is ignited by an ignition device before the compression top dead center and is thus burned by flame propagation in the engine body, and then the unburned air-fuel mixture is burned by compression ignition.

When the geometric compression ratio of an engine body is set to 13:1 or more and the engine body operates in a preset high load region, the effective compression ratio of the engine body is set to 12:1 or more with a difference from the geometric compression ratio being within 2, a gas to be introduced into a combustion chamber is supercharged by a supercharging system, fuel is injected at least in a compression stroke by an injector, and after the fuel injection is finished, an air-fuel mixture in the combustion chamber is ignited by an ignition device before the compression top dead center and is thus burned by flame propagation in the engine body, and then the unburned air-fuel mixture is burned by compression ignition.

A control apparatus for a compression autoignition engine controls compression autoignition by ignition. The control apparatus includes an injector, a spark plug, and a controller. The controller controls the injector so that fuel is injected by a plurality of divided injections, and thereafter, outputs a control signal to the spark plug at predetermined ignition timing so that, by ignition, unburned air-fuel mixture combusts by autoignition. Control is performed so that, when load on the engine is high, an amount of fuel injected at later timing among the plurality of injections becomes larger than when the load is low.