Patent ID: 6123273
Filing Date: 2000-09-26
Classification: F23C,F23D

Abstract:
A dual-fuel nozzle for a gas turbine combustor, comprising:a gaseous/liquid fuel nozzle defining an axis and including a liquid fuel nozzle terminating in a liquid fuel tip for injecting liquid fuel in a spray pattern toward a flame zone downstream of said nozzle when said gaseous/liquid fuel nozzle is operated in a liquid fuel mode;a sleeve surrounding at least a portion of said gaseous/liquid fuel nozzle and in part defining a generally axially extending air flow passage convergent in a downstream direction toward said axis, said sleeve terminating in an axial plane no further upstream than said liquid fuel tip, said axial flow passage decreasing in cross-sectional area in a downstream direction to accelerate air flow through said passage;said gaseous/liquid fuel nozzle including a fuel gas nozzle comprised of a tubular member between said sleeve and said liquid fuel nozzle defining an annular passageway about said liquid fuel nozzle and a plurality of apertures in said tubular member spaced upstream from said liquid fuel tip and opening through said tubular member for flowing fuel gas into said converging flow passage when said gaseous/liquid fuel nozzle is operated in a fuel gas mode;a first air swirler upstream of said fuel tip and said apertures for swirling air introduced into said air flow passage and delivering the swirling air about said liquid fuel spray pattern when in said liquid fuel mode and mixing with the fuel gas when in said fuel gas mode; anda second air swirler about said sleeve and disposed axially downstream of said first air swirler for swirling air received about said sleeve and flowing swirled air about said liquid fuel spray pattern;whereby impingement of liquid fuel onto said gaseous/liquid fuel nozzle is substantially avoided.