Abstract: In this engine control device for controlling an engine with a turbocharger, a rotation speed increase mode includes at least one stage of fuel injection in one combustion cycle of the engine, a high-idle mode includes at least two stages of fuel injection in one combustion cycle of the engine, and a high-idle mode execution unit is configured to retard the timing of the second stage fuel injection in one combustion cycle of the engine in the high-idle mode, relative to the timing of the first stage fuel injection in one combustion cycle of the engine in the rotation speed increase mode.

Abstract: A piston of an internal combustion engine configured to be reciprocable along an axial direction in a cylinder includes a cavity formed to be recessed in a center of a piston top surface, and an outer circumferential edge portion located on a radially outer side of the cavity in the piston top surface. The cavity includes a lip portion, a raised portion, and a curved portion. The curved portion includes an outer circumference-side curved surface which includes a curved surface connected to the lip portion, an inner circumference-side concave surface which is located on a radially inner side of an outer circumference-side curved surface and includes a surface connected to a raised portion, the inner circumference-side concave surface including a deepest portion of the cavity, and a convex surface formed between the outer circumference-side curved surface and the inner circumference-side concave surface, as well as protruding upward.

Abstract: An ammonia engine includes: an engine body which includes a first cylinder and a second cylinder; an air supply unit which supplies air to each of the first cylinder and the second cylinder; an ammonia supply unit which supplies ammonia to each of the first cylinder and the second cylinder; an ammonia amount adjustment unit which adjusts an ammonia supply amount to the second cylinder by the ammonia supply unit to be larger than an ammonia supply amount to the first cylinder; and an exhaust gas supply unit which supplies an exhaust gas generated by the second cylinder to the first cylinder.

Abstract: A piston of an internal combustion engine configured to be reciprocable along an axial direction in a cylinder includes a cavity formed to be recessed in a center of a piston top surface, and an outer circumferential edge portion located on a radially outer side of the cavity in the piston top surface. The cavity includes a lip portion which has an inclined surface extending obliquely downward from the outer circumferential edge portion toward a radially inner side, a raised portion protruding upward from a bottom of the cavity, and a curved portion connecting the raised portion and the lip portion.