A pilot burner for a combustor includes an inner conduit configured to deliver a fuel, and an outer conduit concentric with the inner conduit and configured to deliver air. An inner wall defines an inner plenum, and a partition wall is radially outward of the inner wall and defines an intermediate plenum with at least a portion of the inner wall. Exit passages fluidly couple the inner plenum to the intermediate plenum. An outer wall defines an outer plenum with at least a portion of the partition wall. A crossover section includes passages fluidly coupling the inner conduit to the outer plenum, and passages fluidly coupling the outer conduit to the inner plenum. An end plate includes openings to direct fuel, air for combustion, and air for cooling from the respective plenums.

A premixer array for a gas turbine engine includes a plurality of swirled premixer tubes and a plurality of non-swirled premixer tubes. The premixer array further includes a pilot tube for providing a pilot product. The plurality of swirled premixer tubes may guide and spread out the pilot product in a radial direction, in a circumferential direction, or both in a radial direction and a circumferential direction. The plurality of swirled premixer tubes may include clockwise swirled and counterclockwise swirled premixers. Also, included is a method of controlling the flow of pilot products.

A fuel nozzle device for a gas turbine engine includes a nozzle body extending in an axial direction and projecting into the combustion chamber, and swirler including a tubular portion concentrically surrounding the nozzle body, a deflector formed as a hollow shell concentrically surrounding the tubular portion, and a plurality of swirl vanes extending between the tubular portion and the deflector. Each swirl vane extends along a logarithmic spiral around an axial center of the nozzle body between the tubular portion and the deflector with a certain meridian crossing angle α and a certain twist angle Φ such that the outer peripheral inclination angle θ is smaller than the stacking angle β of the swirl vane when the swirl vane is manufactured by an additive manufacturing process with a front end up orientation.

A fuel nozzle includes a center body that extends from an upstream end to a downstream end. A nozzle tip, which is fixedly coupled to the downstream end of the center body, includes an outer annular wall that has a forward end and an aft end. A solid aft wall is disposed at the aft end of the outer annular wall. The solid aft wall and the outer annular wall at least partially define a plenum. A nozzle portion, which is disposed within the plenum, includes an inner annular wall and an impingement wall. The impingement wall is spaced apart from the solid aft wall and defines a plurality of apertures configured to direct fluid to impinge upon the solid aft wall. A plurality of outlets is defined in the outer annular wall forward of the solid aft wall to direct post-impingement fluid from the nozzle tip.

A gas turbine engine including a compressor section, a combustor for combusting a fuel, and a turbine. Compressed air flows through a combustion liner of the combustor in a bulk airflow direction. The combustor includes a primary fuel nozzle and a secondary fuel nozzle. The secondary fuel nozzle is downstream of the primary fuel nozzle in the bulk airflow direction. The primary fuel nozzle is configured to inject a primary portion of the fuel into a primary combustion zone, and the secondary fuel nozzle is configured to inject a secondary portion of the fuel into a secondary combustion zone. The secondary combustion zone is located downstream of the primary combustion zone in the bulk airflow direction. The fuel may be one of diatomic hydrogen fuel and a hydrogen enriched fuel.

An injection system includes an inner nozzle body defining a first air path along a longitudinal axis. The first air path defines a converging-diverging section between an upstream portion of the first air path and an outlet orifice of the first air path. A main orifice is defined at a narrowest portion of the converging-diverging section. A fuel circuit wall is outboard of the inner nozzle body. A fuel path is defined between the fuel circuit wall and the inner nozzle body. An outer nozzle body outboard of the fuel circuit wall has a second air path defined through the inner nozzle body for communication of air from the outer nozzle body into the first air path, wherein the second air path meets the first air path at a second orifice in the first air path downstream of the main orifice of the inner nozzle body.

A gas turbine engine includes combustion apparatus defining a volume, a compressor, a cooling air supply feed from the compressor, and a Helmholtz resonator. The Helmholtz resonator has a neck and a chamber having an attenuation volume and which is in fluid communication with the attenuation volume, the cooling air supply feed is connected to the Helmholtz resonator and includes a valve arrangement. In a first engine operating condition, the valve arrangement is closed and the Helmholtz resonator attenuates acoustic frequencies in a first range and, in a second engine operating condition, the valve arrangement is open whereby cooling air purges the attenuation volume and the Helmholtz resonator attenuates acoustic frequencies in a second range.

A combustor having bundled tube fuel nozzles is provided. At least one of the fuel nozzles has a dynamics-mitigating adapter removably coupled thereto. The adapter includes a mounting body defining at least one flow passage aligned with an inlet of at least one tube of the at least one fuel nozzle. The at least one flow passage extends an axial length of the at least one tube. The adapter may include extenders aligned with each tube of the fuel nozzle, and the extenders may have identical or different lengths. Adapters may be used for each fuel nozzle of the combustor. The mounting body may be a monolithic unit through which the flow passages are defined or may include a plurality of extenders affixed to and extending upstream of the mounting body.

An igniter for a combustor of a turbomachine includes a fuel inlet in fluid communication with a mixing plenum. The mixing plenum is positioned upstream of a mixing channel. An air inlet is in fluid communication with the mixing plenum and an ignition source is in operative communication with the mixing channel. The igniter may include a mounting flange configured for coupling the igniter to the combustor. The ignition source may be positioned proximate to a downstream end of the mixing channel and upstream of the mounting flange. The mixing channel may define a venturi shape. The venturi shape includes a converging section between an upstream end of the mixing channel and a venturi throat.

A burner assembly includes a plurality of burners for mixing fuel and air. Each of the plurality of burners includes: at least one fuel nozzle for injecting the fuel; and a mixing passage into which the fuel injected from the at least one fuel nozzle and the air are introduced. Each of the at least one fuel nozzle includes a protruding portion protruding upstream of an inlet of the mixing passage in a flow direction of the air. Each of the at least one fuel nozzle includes at least one fuel injection hole formed on a side surface of the protruding portion. A top surface of the protruding portion includes a convex curved surface.