An ignition system for an internal combustion engine includes an igniter having an igniter housing with a combustion prechamber formed therein, and a piston movable within the igniter housing to increase a pressure of an ignition charge of fuel and air within the combustion prechamber to an autoignition threshold. The ignition system includes a hydraulic actuator to apply an actuating force to the piston. Related methodology is disclosed.

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%.

A diesel engine employs a turbulent jet ignition system and method. In another aspect, diesel fuel and air are premixed prior to introduction of the mixture into a main engine combustion chamber. A further aspect employs a turbocharger compressor to boost air pressure into a main piston combustion chamber and/or an ignition pre-chamber for missing with a heavy fuel, such as diesel.

An ignition system for a gaseous fuel engine includes an igniter and an actuator structured to apply an actuating force to a piston within the igniter, to autoignite an ignition charge of fuel and air within the igniter. A housing of the igniter includes a gas orifice having a flow area that is increased between a combustion pre-chamber in the igniter and a main combustion chamber in the engine, to limit velocity of outgoing combustion gases to below a threshold velocity for engine mis-fire.

An engine has, for each cylinder, a combustion chamber and a combustion pre-chamber communicating with the combustion chamber. First and second spark plugs are associated with the pre-chamber and combustion chamber, respectively. Gasoline is injected by an injector device directly into the combustion chamber and/or by an injector device into a cylinder intake duct. There is no device for injecting gasoline, air or an air/gasoline mixture directly into the pre-chamber. The engine operates with an air/gasoline mixture substantially corresponding to stoichiometric, for compatibility with an exhaust system having a trivalent catalyst. The pre-chamber is not used for engine operation with poor dosing, but to increase resistance to engine detonation. The engine can thus be configured with a high compression ratio, with a significant reduction in fuel consumption at the same power level. The second spark plug is only activated at low and medium engine loads to stabilize combustion.

A method for combustion in a combustion chamber of an internal combustion engine includes mixing fuel and air to form a charge, flowing a first portion of the charge to the main chamber of an engine and a second portion of the charge to the pre-chamber volume of an engine, igniting the second portion of the charge in the pre-chamber volume, and delivering the ignited second portion of the charge to the main chamber.

A method for combustion in a combustion chamber of an internal combustion engine includes mixing fuel and air to form a charge, flowing a first portion of the charge to the main chamber of an engine and a second portion of the charge to the pre-chamber volume of an engine, igniting the second portion of the charge in the pre-chamber volume, and delivering the ignited second portion of the charge to the main chamber.

A rotary engine including a rotor sealingly received within an internal cavity of an outer body to define a plurality of combustion chambers having a variable volume, a pilot subchamber located in a wall of the outer body, the pilot subchamber in fluid communication with the internal cavity via at least two spaced apart transfer holes defining a flow restriction between the pilot subchamber and the internal cavity, a pilot fuel injector in fluid communication with the pilot subchamber, an ignition element configured for igniting fuel in the pilot subchamber, and a main fuel injector extending through the stator body and communicating with the cavity at a location spaced apart from the pilot subchamber. A method of combusting fuel in a rotary engine is also discussed.

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%.

A precombustion chamber gas engine includes a main-chamber forming portion forming a main combustion chamber, a precombustion-chamber forming portion forming a precombustion chamber including a small-diameter cylinder chamber communicating with the main combustion chamber via a plurality of nozzle holes and a large-diameter cylinder chamber, an ignition device disposed in the large-diameter cylinder chamber of the precombustion chamber, and a precombustion-chamber-gas supply device for supplying a precombustion-chamber fuel gas to the precombustion chamber not via the main combustion chamber. The nozzle hole is formed so that a precombustion-chamber-side straight line passing through a central position of a precombustion-chamber-side opening of the nozzle hole and parallel to an extending direction of a central line of the precombustion-chamber-side opening of the nozzle hole intersects with a main-chamber-side straight line passing through a central position of a main-chamber-side opening of the nozzle hole and parallel to an extending direction of a central line of the main-chamber-side opening of the nozzle hole, and an acute angle between a precombustion chamber central axis of the precombustion chamber and the precombustion-chamber-side straight line is smaller than an acute angle between the precombustion chamber central axis and the main-chamber-side straight line.