A combustor nozzle assembly and a gas turbine combustor including the same are provided. The combustor nozzle assembly includes a central nozzle tube, an inner nozzle tube surrounding the central nozzle tube in a spaced-apart state, an outer nozzle tube surrounding the inner nozzle tube in a spaced-apart state, a pilot fuel injector provided between the central nozzle tube and the inner nozzle tube, and a main fuel injector provided between the inner nozzle tube and the outer nozzle tube.

A fuel nozzle for a gas turbine engine that includes: an elongated centerbody; an elongated peripheral wall formed about the centerbody so to define a primary flow annulus; a primary fuel and air supply in fluid communication with the primary flow annulus; and a pilot nozzle. The pilot nozzle, formed in the centerbody, may have axially elongated air and mixing tubes extending between inlets and outlets defined, respectively, through upstream and downstream faces of the pilot nozzle. A secondary air supply may be communicate with the inlets of the air and mixing tubes. A fuel port may be positioned in the mixing tubes for connecting each to a secondary fuel supply. An uninterrupted sidewall sealing structure in each of the air tubes may segregate an air flow therethrough from the secondary fuel supply. The air and mixing tubes may be configured as canted tubes so to induce a downstream swirling flow.

A system and method for flame stabilization is provided that forestalls incipient lean blow out by improving flame stabilization. A combustor profile is selected that maintains desired levels of power output while minimizing or eliminating overboard air bleed and minimizing emissions. The selected combustor profile maintains average shaft power in a range of from approximately 50% up to full power while eliminating overboard air bleed in maintaining such power settings. Embodiments allow for a combustor to operate with acceptable emissions at lower flame temperature. Because the combustor can operate at lower bulk flame temperatures during part power operation, the usage of inefficient overboard bleed can be reduced or even eliminated.

A combustor assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, a combustion chamber, and a fuel injector assembly in communication with the combustion chamber that has a swirler body situated about a nozzle to define an injector passage that converges to a throat. The throat is defined at a distance from the combustion chamber. The nozzle includes a primary fuel injector and an array of secondary plain jet fuel injectors.

A combustor nozzle assembly and a gas turbine combustor including the same are provided. The combustor nozzle assembly includes a central nozzle tube, an inner nozzle tube surrounding the central nozzle tube in a spaced-apart state, an outer nozzle tube surrounding the inner nozzle tube in a spaced-apart state, a pilot fuel injector provided between the central nozzle tube and the inner nozzle tube, and a main fuel injector provided between the inner nozzle tube and the outer nozzle tube.

A combustor assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, a combustion chamber, and a fuel injector assembly in communication with the combustion chamber that has a swirler body situated about a nozzle to define an injector passage that converges to a throat. The throat is defined at a distance from the combustion chamber. The nozzle includes a primary fuel injector and an array of secondary plain jet fuel injectors.

A fuel delivery system for a combustor of a gas turbine engine including a primary fuel tank configured to store a primary fuel, a secondary fuel tank configured to store a secondary fuel, a swirler configured to produce a main flame within a combustion chamber of the combustor, and a fuel nozzle configured to produce a pilot flame within the combustion chamber of the combustor. The fuel nozzle includes a nozzle outlet that is located proximate to an end of the swirler or at the end of the swirler, the end of the swirler being located at an inlet of the combustor. The fuel delivery system also includes a primary fuel line fluidly connecting the primary fuel tank to the fuel nozzle and a secondary fuel line fluidly connecting the secondary fuel tank to the swirler.

A combustor assembly for a gas turbine engine according to an example of the present disclosure includes, among other things, a combustion chamber, and a fuel injector assembly in communication with the combustion chamber that has a swirler body situated about a nozzle to define an injector passage that converges to a throat. The throat is defined at a distance from the combustion chamber. The nozzle includes a primary fuel injector along a first fuel injector axis and at least one secondary plain jet fuel injector axially forward of the primary fuel injector.

A fuel delivery system for a combustor of a gas turbine engine including a primary fuel tank configured to store a primary fuel, a secondary fuel tank configured to store a secondary fuel, a swirler configured to produce a main flame within a combustion chamber of the combustor, and a fuel nozzle configured to produce a pilot flame within the combustion chamber of the combustor. The fuel nozzle includes a nozzle outlet that is located proximate to an end of the swirler or at the end of the swirler, the end of the swirler being located at an inlet of the combustor. The fuel delivery system also includes a primary fuel line fluidly connecting the primary fuel tank to the fuel nozzle and a secondary fuel line fluidly connecting the secondary fuel tank to the swirler.

A fuel nozzle apparatus for a gas turbine engine includes: a first pilot fuel injector disposed on a centerline axis of the fuel nozzle which defines a direction of air flow through the fuel nozzle, the first pilot fuel injector being of a pressure atomizing type; an annular second pilot fuel injector at least partially surrounding the first pilot fuel injector, the second pilot fuel injector being of an air blast type and having a fuel outlet disposed axially downstream and radially outboard of the first pilot fuel injector; an annular venturi surrounding the first and second pilot fuel injectors, the venturi including a throat of minimum diameter; an array of inner swirl vanes extending between the first pilot fuel injector and the second pilot fuel injector; and an array of outer swirl vanes extending between the second pilot fuel injector and the venturi.