Abstract: An engine includes: a piston including a cavity; a cylinder head configured so as to form a combustion chamber having a pent roof shape; a fuel injection valve configured to inject fuel from a second half of a compression stroke until a first half of an expansion stroke; and a spark plug arranged at a position corresponding to an upper side of the cavity. Injection openings which are arranged in a circumferential direction surrounding a longitudinal axis of the valve and through each of which the fuel is injected in a direction inclined relative to the longitudinal axis by a predetermined angle is formed such that when a height of a ceiling of the combustion chamber at a position corresponding to an edge end portion of the cavity in an injection direction of the injection opening is large, the injection angle of the injection opening is large.

Abstract: An engine includes: a piston including a cavity; a cylinder head configured to form a combustion chamber having a pent roof shape; a fuel injection valve configured to inject fuel from a second half of a compression stroke until a first half of an expansion stroke; and a spark plug arranged at a position corresponding to an upper side of the cavity. Injection openings are arranged in a circumferential direction surrounding a longitudinal axis of the valve. The combustion chamber at a compression top dead center is divided into a plurality of fuel injection regions, located in respective injection directions of the injection openings, by vertical surfaces extending radially from the longitudinal axis through a middle between adjacent injection openings. When a volume of the fuel injection region located in the injection direction of the injection opening is large, an opening area of the injection opening is large.

Abstract: An engine includes: a piston including a cavity; a cylinder head configured so as to form a combustion chamber having a pent roof shape; a fuel injection valve configured to inject fuel in a period from a second half of a compression stroke until a first half of an expansion stroke; and a spark plug arranged at a position corresponding to an upper side of the cavity. Injection openings which are arranged in a circumferential direction surrounding a longitudinal axis of the valve and through each of which the fuel is injected in a direction inclined relative to the longitudinal axis by a predetermined angle is formed such that when a height of a ceiling of the combustion chamber at a position corresponding to an edge end portion of the cavity in an injection direction of the injection opening is large, the injection angle of the injection opening is large.

Abstract: An engine includes: a piston including a cavity; a cylinder head configured to form a combustion chamber having a pent roof shape; a fuel injection valve configured to inject fuel from a second half of a compression stroke until a first half of an expansion stroke; and a spark plug arranged at a position corresponding to an upper side of the cavity. Injection openings are arranged in a circumferential direction surrounding a longitudinal axis of the valve. The combustion chamber at a compression top dead center is divided into a plurality of fuel injection regions, located in respective injection directions of the injection openings, by vertical surfaces extending radially from the longitudinal axis through a middle between adjacent injection openings. When a volume of the fuel injection region located in the injection direction of the injection opening is large, an opening area of the injection opening is large.

Abstract: A control value calculation part includes an in-cylinder state estimation part that estimates a state to which the cylinder belongs between a plurality of PM-PN generation states. The plurality of PM-PN generation states are states in which a particulate matter is easily generated as compared with the other state, and are different from each other in a cause to generate the particulate matter. Further, in a case where it is determined that an operation state of an engine is a PM-PN exhaust state, the control value calculation part calculates a control value of an actuator in such a way to eliminate the PM-PN generation state according to the PM-PN generation state to which the state in the cylinder belongs.