PREFILMING AIR BLAST (PAB) PILOT FOR LOW EMISSIONS COMBUSTORS

摘要

A pilot fuel injector is provided for a fuel nozzle of a gas turbine engine. The pilot fuel injector can include an axially-elongated, inner pilot centerbody wall extending from an upstream end to a downstream end, with the axially-elongated, inner pilot centerbody wall having a diverging-converging orientation with respect to a centerline axis to define a hollow tube having an upstream diameter, a throat, and a downstream diameter such that the throat has an inner diameter that is less than both of the upstream diameter and the downstream diameter. The pilot fuel injector also includes a center air circuit positioned at the upstream end, and an annular fuel passage defining the downstream end and intersecting with the centerbody wall at a pilot fuel metering orifice. A pilot fuel film surface is downstream from the annular fuel passage.

主权项

1. A pilot fuel injector of a fuel nozzle of a gas turbine engine, comprising:
an axially-elongated, inner pilot centerbody wall extending from an upstream end to a downstream end, wherein the axially-elongated, inner pilot centerbody wall has a diverging-converging orientation with respect to a centerline axis to define a hollow tube having an upstream diameter, a throat, and a downstream diameter, and wherein the throat has an inner diameter that is less than both of the upstream diameter and the downstream diameter; a center air circuit positioned at the upstream end of the hollow tube, wherein the center air circuit is defined by a center swirler having center swirl vanes; an annular fuel passage defining the downstream end of the pilot fuel injector, the fuel passage intersecting with the centerbody wall at a pilot fuel metering orifice; and a pilot fuel film surface downstream from the annular fuel passage, wherein the throat is positioned between the center swirler and the pilot fuel metering orifice.