Gas-fueled, compression ignition engine with maximized pilot ignition intensity

A method of operating an engine having a cylinder which includes an engine head and a piston which is reciprocateably translatable in the cylinder to define a variable-volume combustion chamber between the engine head and the piston, the method comprising the steps of:

• (A) performing an intake stroke of the piston;
• (B) performing a compression stroke of the piston after the intake stroke;
• (C) admitting a gaseous fuel charge and air into the combustion chamber during one of the intake stroke and the compression stroke;
• (D) injecting a pilot fuel charge into the combustion chamber during the compression stroke, the injecting step being performed by operating an electronically controlled fuel injector coupled to a source of fuel that is ignitable by compression ignition;
• (E) combusting the pilot fuel charge to ignite the gaseous fuel charge, wherein the steps of injecting the pilot fuel charge and igniting the pilot fuel charge comprise, on a cycle-by-cycle, full load and speed range basis
• (1) initiating pilot fuel injection at a time, Tp,
• (2) continuing pilot fuel injection for a duration, Dp, and
• (3) igniting the pilot fuel charge by compression-ignition at an autoignition point, Ti, occurring an ignition delay interval Di after Tp;
• and
• (4) controlling at least one of Tp, Dp, and Di to maintain Dp/Di<1.

A method for the pilot ignition of a mixture of a gaseous fuel and air in a combustion chamber of an internal combustion engine, the method comprising:

• (A) injecting a pilot fuel charge into a combustion chamber either before or after the gaseous fuel is admitted into the combustion chamber, the pilot fuel being capable of autoignition by compression ignition;
• (B) igniting the pilot fuel charge by causing a piston of the engine to undergo a compression stroke;
• and
• (C) controlling at least one of pilot fuel injection timing, pilot fuel injection duration, and autoignition timing to generate peak power in excess of 100 kW/l from the combustion of the pilot fuel charge in the combustion chamber.

An engine comprising:

• (A) a cylinder which includes an engine head and a piston which is reciprocateably translatable in said cylinder to define a variable-volume combustion chamber between said engine head and said piston;
• (B) a gaseous fuel source positioned in fluid communication with said combustion chamber during one of an intake stroke of said piston and a compression stroke of said piston;
• (C) an air source positioned in fluid communication with said combustion chamber during said intake stroke of said piston;
• (D) a pilot fuel injector which is configured to inject a charge of pilot fuel into said combustion chamber during the compression stroke of said piston;
• and
• (E) a controller which controls a device comprising at least said pilot fuel injector, said gaseous fuel source, and said air source such that a timing, Tp, of initiation of pilot fuel injection, a pilot fuel injection duration, Dp, and an ignition delay period, Di, are such that Dp/Di is <1.

An engine comprising:

• (A) a cylinder which includes an engine head and a piston which is reciprocateably translatable in said cylinder to define a variable-volume combustion chamber between said engine head and said piston;
• (B) a gaseous fuel source positioned in fluid communication with said combustion chamber during one of an intake stroke of said piston and a compression stroke of said piston;
• (C) an air source positioned in fluid communication with said combustion chamber during the intake stroke of said piston;
• (D) a pilot fuel injector which is configured to inject a charge of pilot fuel into said combustion chamber during the compression stroke of said piston;
• and
• (E) means for controlling a device comprising at least one of said gaseous fuel source, said pilot fuel injector, and said air source such that a timing, Tp, of initiation of pilot fuel injection, a pilot fuel injection duration, Dp, and an ignition delay period, Di, are such that Dp/Di is <1.