Differential pressure induced purging fuel injectors

摘要

A fuel injector includes an annular main fuel nozzle received within an annular nozzle housing, a main nozzle fuel circuit having at least one annular leg, and a pilot nozzle fuel circuit. Spray orifices of the leg extend through the fuel nozzle and spray wells through the housing are aligned with the orifices. The nozzle is designed to generate sufficient static pressure differentials between at least two different ones of the spray wells to purge the main nozzle fuel circuit. Spray well portions may be asymmetrically flared out with respect to a spray well centerline in different local streamwise directions. Some of the spray well portions may be asymmetrically flared out in a local upstream direction and others in a local downstream direction. The local streamwise direction may have an axial component parallel to a nozzle axis about which the annular nozzle housing is circumscribed and a circumferential component around the nozzle housing.