Abstract: A system includes an oxidant compressor and a gas turbine engine turbine, which includes a turbine combustor, a turbine, and an exhaust gas compressor. The turbine combustor includes a plurality of diffusion fuel nozzles, each including a first oxidant conduit configured to inject a first oxidant through a plurality of first oxidant openings configured to impart swirling motion to the first oxidant in a first rotational direction, a first fuel conduit configured to inject a first fuel through a plurality of first fuel openings configured to impart swirling motion to the first fuel in a second rotational direction, and a second oxidant conduit configured to inject a second oxidant through a plurality of second oxidant openings configured to impart swirling motion to the second oxidant in a third rotational direction. The first fuel conduit surrounds the first oxidant conduit and the second oxidant conduit surrounds the first fuel conduit.

Abstract: A combustor includes a central fuel nozzle assembly and a plurality of outer fuel nozzle assemblies, each of the plurality of outer fuel nozzle assemblies having a center body and an outer shroud, the plurality of outer fuel nozzle assemblies being configured to abut one another in a surrounding relationship to the central cylinder such that no gaps are present between any two abutting ones of the plurality of outer fuel nozzle assemblies. One or more of the plurality of fuel nozzle assemblies may traverse axially back and forth according to embodiments of the invention.

Abstract: A combustor includes an end cap having upstream and downstream surfaces and a cap shield surrounding the upstream and downstream surfaces. First and second sets of premixer tubes extend from the upstream surface through the downstream surface. A first fuel conduit supplies fuel to the first set of premixer tubes. A casing circumferentially surrounds the cap shield to define an annular passage, and a second fuel conduit supplies fuel through the annular passage to the second set of premixer tubes. A method for supplying fuel to a combustor includes flowing a working fluid through first and second sets of premixer tubes, flowing a first fuel into the first set of premixer tubes, and flowing a second fuel through an annular passage surrounding the end cap and into the second set of premixer tubes.

Abstract: A nozzle includes a fuel plenum and an air plenum downstream of the fuel plenum. A primary fuel channel includes an inlet in fluid communication with the fuel plenum and a primary air port in fluid communication with the air plenum. Secondary fuel channels radially outward of the primary fuel channel include a secondary fuel port in fluid communication with the fuel plenum. A shroud circumferentially surrounds the secondary fuel channels. A method for mixing fuel and air in a nozzle prior to combustion includes flowing fuel to a fuel plenum and flowing air to an air plenum downstream of the fuel plenum. The method further includes injecting fuel from the fuel plenum through a primary fuel passage, injecting fuel from the fuel plenum through secondary fuel passages, and injecting air from the air plenum through the primary fuel passage.

Abstract: The present application provides a variable volume combustor for use with a gas turbine engine. The variable volume combustor may include a liner, a number of micro-mixer fuel nozzles positioned within the liner, and a linear actuator so as to maneuver the micro-mixer fuel nozzles axially along the liner.

Abstract: The present application provides a combustor for use with flow of fuel and a flow of air in a gas turbine engine. The combustor may include a number of micro-mixer fuel nozzles positioned within a liner and an air bypass system position about the liner. The air bypass system variably allows a bypass portion of the flow of air to bypass the micro-mixer fuel nozzles.

Abstract: The system may include a turbine engine. The turbine engine may include a fuel nozzle. The fuel nozzle may include an air path. The fuel nozzle may also include a fuel path such that the fuel nozzle is in communication with a combustion zone of the turbine engine. Furthermore, the fuel nozzle may include a resonator. The resonator may be disposed in the fuel nozzle directly adjacent to the combustion zone.

Abstract: A combustor includes an end cap that extends radially across at least a portion of the combustor. The end cap includes an upstream surface axially separated from a downstream surface. A plurality of tubes extend from the upstream surface through the downstream surface of the end cap to provide fluid communication through the end cap. Each tube in a first set of the plurality of tubes has an inlet proximate to the upstream surface and an outlet downstream from the downstream surface. Each outlet has a first portion that extends a different axial distance from the inlet than a second portion.

Abstract: A system for reducing modal coupling of combustion dynamics includes a plurality of combustors, and at least one fuel injector in each of the plurality of combustors. The system also includes structure for dithering a combustion instability frequency in at least one combustor in the plurality of combustors. A method for reducing modal coupling of combustion dynamics includes flowing a compressed working fluid at a temperature to a plurality of combustors and flowing a fuel to at least one fuel injector in each of the plurality of combustors. The method further includes dithering at least one of the temperature of the compressed working fluid flowing to the plurality of combustors or the fuel flow to the at least one fuel injector in at least one combustor in the plurality of combustors.

Abstract: A gas turbine engine is provided and includes a fuel circuit, including multiple fuel circuit branches, a combustor having a first interior in which a first fuel supplied thereto by any one of the multiple fuel circuit branches is combustible, a turbine, a transition zone, including a second interior in which a second fuel supplied thereto by any one of the multiple fuel circuit branches, the second fuel including gas receivable by the fuel circuit from an external source, and the products of the combustion of the first fuel are combustible, the transition zone being disposed to fluidly couple the combustor and the turbine to one another, and a plurality of fuel injectors which supply the second fuel to the second interior in any one of a single axial stage, multiple axial stages, a single axial circumferential stage and multiple axial circumferential stages.

Abstract: Disclosed is a method of operating a secondary fuel nozzle for a turbomachine combustor including delivering a flow of pilot fuel through a pilot fuel channel toward a combustion zone and delivering a flow of air through a plurality of transfer passages arranged around the pilot fuel channel toward the combustion zone. The flow of pilot fuel and the flow of air are combusted in the combustion zone, and a flow of transfer fuel is delivered through the plurality of transfer passages for combustion. A secondary fuel nozzle includes a pilot fuel channel extending along the fuel nozzle to deliver a flow of pilot fuel to a combustion zone. A plurality of transfer passages are arranged around the pilot fuel channel and are configured to deliver a flow of air for combustion with the flow of pilot fuel and to deliver a flow of transfer fuel to the combustion zone.

Abstract: A method for controlling a gas turbine combustion system includes supplying an ultra low calorific fuel to a combustor of the combustion system through a first fuel circuit, controlling a supply of the ultra low calorific fuel through a second fuel circuit as required to control the volumetric flow of the ultra low calorific fuel through the combustor, and combusting the ultra low calorific fuel in the combustor.

Abstract: A combustor may include a number of nozzles, a first fuel source with a low reactivity fuel therein, a second fuel source with a high reactivity fuel therein, and a primary valve for varying the flow of the low reactivity fuel and the high reactivity fuel delivered to the nozzles.

Abstract: A nozzle includes a center body that defines an axial centerline and a shroud circumferentially surrounding at least a portion of the center body to define an annular passage between the center body and the shroud. A plurality of vanes between the center body and the shroud comprise a radially outward portion separated from the shroud. A method for enhancing flow through a nozzle includes flowing a fuel through a center body and flowing a fluid stream across a vane located between the center body and a shroud surrounding at least a portion of the center body. The method further includes flowing the fluid stream between a radially outward portion of the vane and the shroud, wherein the radially outward portion of the vane is separated from the shroud.

Abstract: A fuel/air mixing tube for use in a fuel/air mixing tube bundle is provided. The fuel/air mixing tube includes an outer tube wall extending axially along a tube axis between an inlet end and an exit end, the outer tube wall having a thickness extending between an inner tube surface having a inner diameter and an outer tube surface having an outer tube diameter. The tube further includes at least one fuel injection hole having a fuel injection hole diameter extending through the outer tube wall, the fuel injection hole having an injection angle relative to the tube axis. The invention provides good fuel air mixing with low combustion generated NOx and low flow pressure loss translating to a high gas turbine efficiency, that is durable, and resistant to flame holding and flash back.

Abstract: Embodiments of the present application include a combustor assembly. The combustor assembly may include a combustion chamber, a first plenum, a second plenum, and one or more elongate air/fuel premixing injection tubes. Each of the elongate air/fuel premixing injection tubes may include a first length at least partially disposed within the first plenum and configured to receive a first fluid from the first plenum. Moreover, each of the elongate air/fuel premixing injection tubes may include a second length disposed downstream of the first length and at least partially disposed within the second plenum. The second length may be formed of a porous wall configured to allow a second fluid from the second plenum to enter the second length and create a boundary layer about the porous wall.

Abstract: The present application provides a premixer for a combustor. The premixer may include a fuel plenum with a number of fuel tubes and a burner tube with a number of air tubes. The fuel tubes extend about the air tubes.

Abstract: A combustor includes a tube bundle that extends radially across at least a portion of the combustor. The tube bundle includes an upstream surface axially separated from a downstream surface. A plurality of tubes extends from the upstream surface through the downstream surface, and each tube provides fluid communication through the tube bundle. A baffle extends axially inside the tube bundle between adjacent tubes. A method for distributing fuel in a combustor includes flowing a fuel into a fuel plenum defined at least in part by an upstream surface, a downstream surface, a shroud, and a plurality of tubes that extend from the upstream surface to the downstream surface. The method further includes impinging the fuel against a baffle that extends axially inside the fuel plenum between adjacent tubes.

Abstract: A nozzle for a combustor is disclosed. The nozzle includes a center body, a burner tube provided around the center body and defining a fuel-air mixing passage therebetween, and an outer peripheral wall provided around the burner tube and defining an air flow passage therebetween. The nozzle further includes a nozzle tip connected to the center body. The nozzle tip includes a pilot fuel passage configured to deliver a flow of pilot fuel to a combustion zone, and a plurality of transfer passages. The plurality of transfer passages are configured to deliver a flow of air for combustion with the flow of pilot fuel in the combustion zone and further configured to deliver a flow of transfer fuel to the combustion zone.

Abstract: A fuel delivery system for a gas turbine engine includes one or more subsets of combustors, and at least two fuel manifolds including a fuel manifold coupled to each combustor subset and configured to deliver fuel to only the subset of combustors during a predetermined gas turbine engine operating mode. A gas turbine engine assembly including a fuel delivery system and a method of operating a gas turbine engine is also described herein.