Patent ID: 11959435
Assignee: SAUDI ARABIAN OIL COMPANY
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F | IPC F

Claim 16:
17. A method, comprising:
designing an engine to operate using passive jet ignition combustion under a first set of engine parameters, wherein passive jet ignition combustion comprises:
injecting fuel from a fuel injector into a main chamber of the engine such that an amount of the fuel is directed into a prechamber to provide a prechamber fuel air mixture in the prechamber and a main chamber fuel air mixture in the main chamber, wherein the prechamber is adjacent to and in fluid communication with the main chamber;
generating a spark in the prechamber to ignite the prechamber fuel air mixture; and
ejecting the ignited prechamber fuel air mixture from the prechamber into the main chamber to ignite the main chamber fuel air mixture,
wherein the first set of engine parameters comprises:
an engine speed ranging from a first minimum speed to a first maximum speed; and
an engine load ranging from a first minimum load to a first maximum load, and

wherein under the first set of engine parameters, a ratio of fuel to air provided in the main chamber and the prechamber after the injecting is a stoichiometric ratio;

designing the engine to operate using passive jet ignition combustion under a second set of engine parameters, the second set of engine parameters comprising:
the engine speed ranging from greater than the first maximum speed to a second maximum speed; and
the engine load ranging from the first minimum load to a second maximum load,

designing the engine to change the ratio of fuel to air provided in the main chamber and the prechamber to an ultra-lean ratio when the engine is operated under a third set of engine parameters,
wherein under the third set of engine parameters, the engine speed is greater than the first maximum speed and the engine load is greater than the second maximum load, and
wherein the ultra-lean ratio comprises more air than fuel; and

operating the engine under different engine parameters by conducting the injecting at different times as a piston cycles in the main chamber.