Abstract: An injection system includes a radial swirler defining an axis and including a plurality of radial swirl vanes configured to direct a radially inward flow of compressor discharge air entering swirler inlets between the radial swirl vanes in a swirling direction around the axis. The radial swirler includes an outlet oriented in an axial direction to direct swirling compressor discharge air in an axial direction. An injector ring is included radially outward from of the swirler inlets. The fuel injector ring is aligned with the axis and includes a plurality of injection orifices directed towards the swirler inlets for injecting fuel into the radial swirler.

Abstract: A fuel injector for a turbomachine includes an outer heat shield configured to sit on and/or within a combustor dome to orient the fuel injector relative to the combustor dome and/or a fuel manifold. An inner surface of the outer heat shield includes an outer heat shield seal surface. The injector also includes a fuel prefilmer seated at least partially within the outer heat shield. An outer surface of the fuel prefilmer includes a prefilmer seal surface configured to mate with the outer heat shield seal surface such that the fuel prefilmer seats on the outer heat shield seal surface and such that the prefilmer seal surface is configured to allow the surfaces to slide relative to one another in both a radial and axial direction.

Abstract: A fuel injector for a multipoint injection system can include a body defining an air cavity for allowing air to flow therethrough and an interior cavity. A fuel is tube disposed at least partially within the interior cavity of the body. The fuel tube can include a first end configured to connect to a fuel injector connector of a fuel manifold, and a second end configured to connect to a fuel distributor of the fuel injector, wherein the fuel injector is configured to be disposed at least partially in a combustor dome. The fuel tube is configured to move in an axial direction to allow flexibility between the fuel manifold and the combustor dome.

Abstract: An air mixer includes an annular body defining a center axis. A plurality of slots are defined in the annular body circumferentially spaced apart from one another. Each slot defines a respective center injection axis extending from an outer surface of the annular body to an inner surface of the annular body. Each respective center injection axis is parallel to a respective plane bisecting the annular body. At least one of the slots is intersected by the respective bisecting plane parallel to its respective center injection axis.

Abstract: A fuel injector for an exhaust heater includes a cover and an air blast nozzle. The cover has a nozzle seat, a fuel inlet, and an air inlet, the nozzle seat arranged along a flow axis. The air blast nozzle is seated in the nozzle seat and has a unibody. The air blast nozzle unibody is in fluid communication with the fuel inlet and the air inlet arranged along the flow axis to port fuel and air into a combustion volume, e.g., to heat a stream of exhaust gas flowing between an engine and a catalytic reactor by combustion with fuel introduced through the fuel inlet and air introduced through the air inlet.

Abstract: A fuel system includes a fuel supply system. A plurality of fuel nozzles are connected in fluid communication with the fuel supply system to supply fuel from a fuel source to be issued for combustion from the fuel nozzles. A cooling system is included, wherein at least one of the fuel nozzles includes a cooling circuit in addition to a fuel circuit for issuing fuel from the fuel supply system for combustion. The cooling circuit includes an inlet and an outlet. The inlet is in fluid communication with the cooling system for circulation of coolant through the cooling circuit and back to the cooling system out the outlet of the cooling circuit for cooling the fuel circuit with the fuel circuit staged off.

Abstract: A multipoint injection system includes a manifold with a plurality of flow passages defined through the manifold in the circumferential direction. The flow passages are spaced apart from one another in an axial direction. A plurality of feed arms extends radially inward from the manifold. Feed arm portions of the flow passages extend through each of the feed arms to respective outlets. The feed arm portions of the flow passages are within the axial width of the manifold. A plurality of injection nozzles are included, each in fluid communication with a respective one of the outlets. Each injection nozzle includes an air passage therethrough with an air inlet. The feed arms each follow a path that is circumferentially offset from the air inlets so each of the feed arms is clear from a flow path directly upstream in the axial direction of each of the air inlets.

Abstract: A fuel injector for a gas turbine engine includes a feed arm defining a conduit extending between an inlet end and an outlet end and a plunger. The plunger is disposed within the conduit and is movable between a plunger first position and a plunger second position. A flow area defined between the plunger and the feed arm is smaller in the plunger first position than in the plunger second position to bias fuel flow through the fuel injector. Fuel systems, gas turbine engines, and methods of controlling fuel flow in gas turbine engine fuel systems are also described.

Abstract: A multipoint injection system includes a manifold with a plurality of flow passages defined through the manifold in the circumferential direction. The flow passages are spaced apart from one another in an axial direction. A plurality of feed arms extends radially inward from the manifold. Feed arm portions of the flow passages extend through each of the feed arms to respective outlets. The feed arm portions of the flow passages are within the axial width of the manifold. A plurality of injection nozzles are included, each in fluid communication with a respective one of the outlets. Each injection nozzle includes an air passage therethrough with an air inlet. The feed arms each follow a path that is circumferentially offset from the air inlets so each of the feed arms is clear from a flow path directly upstream in the axial direction of each of the air inlets.

Abstract: A fluid-gas mixer including a housing, defining a primary axis, for mixing fluid and gas, a mixer nozzle circumscribing the primary axis, wherein an annular gap between an outer surface of the mixer nozzle and an inner surface of the housing defines at least one outer gas path, a swirling gas passage defining an inner gas path for mixing with the outer gas path.

Abstract: A turbomachine fuel injector system includes an air distributor configured to be mounted to and contained within a casing and to provide air to mix with a fuel from one or more fuel distribution systems. The system includes a fuel manifold configured to be mounted indirectly to the casing such that the fuel manifold system is contained within the casing but is independent such that fuel manifold does not touch or directly mount to either an interior of the casing or touch the air distributor within the casing to prevent or reduce thermal transfer from the air distributor to the fuel manifold.

Abstract: In accordance with at least one aspect of this disclosure, a fuel injector can include an annular body defining a gas fuel inlet therein, and a structure extending radially outward from the annular body and configured to extend into an air circuit. The structure can include a gas channel defined within the structure at least partially along a radial length of the structure. The gas channel is in fluid communication with the gas fuel inlet where the structure meets the annular body. The structure also includes a slot opening defined at least partially along a radial length of the structure and configured to fluidically connect the gas channel and the air circuit to all gas fuel to effuse into the air circuit.

Abstract: A nozzle includes a nozzle body defining a liquid circuit extending from a liquid inlet to a liquid outlet. The liquid circuit includes a plurality of spiral liquid passages spiraling radially inward relative to a spray axis. The spiral liquid passages all lie in a plane normal to the spray axis. A manifold assembly includes a plurality of such nozzles. A manifold ring is in fluid communication with the liquid inlet of each of the nozzles to deliver liquid to the nozzles. The nozzles are circumferentially spaced apart around the manifold ring.

Abstract: A method of joining includes applying braze to a braze reservoir in a first component. A second component is engaged to the first component, wherein a joint location is defined between the first and second components. A wicking structure provides flow communication from the braze reservoir to the joint location. The method also includes joining the first and second components together at the joint location by applying heat to the braze to flow the braze from the reservoir through the wicking structure to the joint location to form a braze joint at the joint location.

Abstract: A method for assembling a fuel distribution system for a turbomachine fuel injector includes inserting a liquid fuel distributor into an interior cavity of a shroud to create a liquid fuel distribution circuit between the liquid fuel distributor and the shroud and inserting a gas fuel distributor into the interior cavity of the shroud and into an interior cavity of the liquid fuel distributor to create a gas fuel distribution circuit between the gas fuel distributor and the liquid fuel distributor. The method includes inserting a fuel transfer tube into an outer diameter of the shroud. The method includes brazing or shrink fitting at least one of the fuel transfer tube, the gas fuel distributor, or the liquid fuel distributor to the shroud.

Abstract: A combustor for a gas turbine engine includes an inner combustor wall and an outer combustor wall radially outboard of the inner combustor wall. The inner and outer combustor walls define a combustion space therebetween with an upstream inlet and a downstream outlet. A combustor dome connects between inner and outer combustor walls at the upstream inlet of the combustion space. The combustor dome includes a plurality of circumferentially spaced apart nozzles and a plurality of tiles mounted to the combustor dome to fluidly separate a downstream side of the combustor dome from an upstream side of the combustor dome.

Abstract: A fluid-gas mixer including a housing, defining a primary axis, for mixing fluid and gas, a mixer nozzle circumscribing the primary axis, wherein an annular gap between an outer surface of the mixer nozzle and an inner surface of the housing defines at least one outer gas path, a swirling gas passage defining an inner gas path for mixing with the outer gas path.

Abstract: A fuel system includes a fuel passage for conveying a hydrocarbon fuel. The hydrocarbon fuel is reactive with oxygen to form carbonaceous deposit. A device is disposed in the fuel passage such as to be exposed to the hydrocarbon fuel. The device includes first and second surfaces that are spaced from each other by a clearance gap into which the hydrocarbon fuel can infiltrate. The first and second surfaces are in sliding motion with respect to each other when the device is in operation. A frangible fluoropolymer coating is disposed on at least one of the first or second surfaces along the clearance gap. The coating is subject to the carbonaceous deposit adhering thereon. The coating is configured to allow portions to release by shearing off with the carbonaceous deposit under stress from the sliding motion to uncover a newly exposed face of the coating.

Abstract: A nozzle includes an outer gas flow path, an inner gas flow path radially inward from the outer gas flow path, a liquid flow path defined radially between the inner gas flow path and the outer gas flow path, and a core conduit defined radially inward from the inner gas flow path. An injector assembly includes an outer housing, a nozzle within the outer housing, and an outer housing gas flow path defined radially outward from the nozzle between an inner surface of the outer housing and an outer surface of the nozzle. The nozzle includes an outer gas flow path, an inner gas flow path radially inward from the outer gas flow path, a liquid flow path defined radially between the inner gas flow path and the outer gas flow path and a core conduit defined radially inward from the inner gas flow path.

Abstract: A nozzle includes an outer gas flow path, an inner gas flow path radially inward from the outer gas flow path, a liquid flow path defined radially between the inner gas flow path and the outer air flow path, and a core conduit defined radially inward from the inner gas flow path. An injector assembly includes an outer housing, a nozzle within the outer housing, and an outer housing gas flow path defined radially outward from the nozzle between an inner surface of the outer housing and an outer surface of the nozzle. The nozzle includes an outer gas flow path, an inner gas flow path radially inward from the outer gas flow path, a liquid flow path defined radially between the inner gas flow path and the outer gas flow path and a core conduit defined radially inward from the inner gas flow path.