Abstract: An air shroud for a nozzle includes an air shroud body defining an inlet and an outlet in fluid communication with one another to allow an outer airflow to issue therefrom. The air shroud also includes an air wipe disposed outboard of the air shroud body including a web defining a plurality of air wipe outlets in fluid communication with a downstream surface of the air shroud body such that air can flow through the air wipe outlets and wipe the downstream surface of the air shroud body. The air wipe can be integral with the air shroud body.

Abstract: An air swirler has a radially outer wall bounding an annular passage. The radially outer wall has an axially extending portion and a radially convergent portion which converges towards an outlet of the passage. Downstream of the outlet, the passage facing surface of the radially outer wall becomes divergent. The region in which the passage facing surface of the radially outer wall is convergent then divergent defines the flare. A circumferential and axially extending recess is provided in the radially outer wall opposite the flare. A reinforcement of material with superior wear properties to the material of the main body is built in the recess to a radius which coincides with that of the outer surface of the axially extending portion of the radially outer wall. The reinforcement can conveniently be added to the main body by means of a laser consolidation ALM process.

Abstract: A fuel injector for a lean direct injection fuel nozzle has a pilot air swirler which sits radially outboard of a pilot fuel swirler radially outer wall. The air swirler is bounded on its radially outer side by joined wall portions. One wall portion extends axially and another wall portion converges radially. On the radially inwardly facing surface, the wall portions meet to provide a continuing wall surface of the air swirler which transitions from axial extension to radial convergence over a smooth radius. The curvature of this surface broadly mirrors the radially outwardly facing profile of the pilot fuel swirler radially outer wall. The axially extending wall portion is extended axially to form a first part of a join interface. The radially converging portion is extended in a radial direction to provide a second part of the join interface.

Abstract: A method of injecting fuel in a gas turbine engine includes injecting gaseous fuel from a gaseous fuel circuit of an injector in a first mode, wherein flow of gaseous fuel from the gaseous fuel circuit constricts air flow from an air circuit. The method includes injecting liquid fuel from a liquid fuel circuit in a second mode, idling flow in the gaseous fuel circuit and flowing air through the air circuit for passive purge to prevent liquid fuel from migrating into the gaseous fuel circuit. The method includes injecting a gaseous fuel that lies within a range of different Wobbe Index values, wherein regardless of where the gaseous fuel falls in the range, it does not prevent operation in the first and second modes as described above.

Abstract: A strain reliever for a hollow tube is disclosed. The strain reliever has a fitting dimensioned to fit at a tube segment and a tapered sleeve extending from the fitting. The tapered sleeve is configured to surround the tube segment and to provide relief of strain imposed by forces exerted on the tube. Strain relievers having helical conic and slotted tapered sleeves are also described.

Abstract: An air swirler has a radially outer wall bounding an annular passage. The radially outer wall has an axially extending portion and a radially convergent portion which converges towards an outlet of the passage. Downstream of the outlet, the passage facing surface of the radially outer wall becomes divergent. The region in which the passage facing surface of the radially outer wall is convergent then divergent defines the flare. A circumferential and axially extending recess is provided in the radially outer wall opposite the flare. A reinforcement of material with superior wear properties to the material of the main body is built in the recess to a radius which coincides with that of the outer surface of the axially extending portion of the radially outer wall. The reinforcement can conveniently be added to the main body by means of a laser consolidation ALM process.

Abstract: A fuel injector for a lean direct injection fuel nozzle has a pilot air swirler which sits radially outboard of a pilot fuel swirler radially outer wall. The air swirler is bounded on its radially outer side by joined wall portions. One wall portion extends axially and another wall portion converges radially. On the radially inwardly facing surface, the wall portions meet to provide a continuing wall surface of the air swirler which transitions from axial extension to radial convergence over a smooth radius. The curvature of this surface broadly mirrors the radially outwardly facing profile of the pilot fuel swirler radially outer wall. The axially extending wall portion is extended axially to form a first part of a join interface. The radially converging portion is extended in a radial direction to provide a second part of the join interface.

Abstract: An air shroud for a nozzle includes an air shroud body defining an inlet and an outlet in fluid communication with one another to allow an outer airflow to issue therefrom. The air shroud also includes an air wipe disposed outboard of the air shroud body including a web defining a plurality of air wipe outlets in fluid communication with a downstream surface of the air shroud body such that air can flow through the air wipe outlets and wipe the downstream surface of the air shroud body. The air wipe can be integral with the air shroud body.

Abstract: A flow directing device for imparting swirl on a fluid includes a flow directing body having a first surface and opposed second surface. A flow channel is defined in the first surface of the flow directing body for conducting fluids flowing through the flow directing body. The flow channel includes a channel surface set in from the first surface. A swirl bore extends though the flow directing body from the channel surface to the second surface of the flow directing body at an oblique angle relative to the channel surface for imparting a tangential swirl component onto fluids flowing through the swirl bore. Having an asymmetrical terminus portion of the channel surface, and positioning of the swirl bore within the terminus portion, allow control of the swirl direction for flow within the terminus portion and swirl bore.

Abstract: A method of fabricating a fuel injector is disclosed which includes the steps of forming a structural portion of a fuel injector from an alloy having a first mechanical property, and then adding an alloy having a second mechanical property on a surface area of the structural portion to enhance the mechanical properties of the fuel injector.

Abstract: A flow directing device for imparting swirl on a fluid includes a flow directing body having an inboard surface and opposed outboard surface. A flow channel is defined in the outboard surface of the flow directing body for conducting fluids flowing through the flow directing body. The flow channel includes a channel floor and a sidewall extending from the channel floor to the outboard surface of the flow directing body. A swirl port extends from the sidewall of the flow channel though the flow directing body to the inboard surface of the flow directing body for mitigating pressure loss when discharging fluid from the flow channel.

Abstract: An injector includes a main nozzle body defining a central axis and having a main fuel circuit. A pilot nozzle body is mounted inboard of the main nozzle body. The pilot nozzle body includes a pilot air circuit on the central axis with fuel circuitry radially outboard of the pilot air circuit for delivering fuel to a fuel outlet in a downstream portion of the pilot nozzle body. The fuel circuitry includes a primary pilot fuel circuit configured and adapted to deliver fuel to the fuel outlet and a secondary pilot fuel circuit configured and adapted to deliver fuel to the same fuel outlet.

Abstract: A strain reliever for a hollow tube is disclosed. The strain reliever has a fitting dimensioned to fit at a tube segment and a tapered sleeve extending from the fitting. The tapered sleeve is configured to surround the tube segment and to provide relief of strain imposed by forces exerted on the tube. Strain relievers having helical conic and slotted tapered sleeves are also described.

Abstract: A method of fabricating a fuel injector is disclosed which includes the steps of forming a structural portion of a fuel injector from an alloy having a first mechanical property, and then adding an alloy having a second mechanical property on a surface area of the structural portion to enhance the mechanical properties of the fuel injector.

Abstract: A flow directing device for imparting swirl on a fluid includes a flow directing body having an inboard surface and opposed outboard surface. A flow channel is defined in the outboard surface of the flow directing body for conducting fluids flowing through the flow directing body. The flow channel includes a channel floor and a sidewall extending from the channel floor to the outboard surface of the flow directing body. A swirl port extends from the sidewall of the flow channel though the flow directing body to the inboard surface of the flow directing body for mitigating pressure loss when discharging fluid from the flow channel.

Abstract: A flow directing device for imparting swirl on a fluid includes a flow directing body having a first surface and opposed second surface. A flow channel is defined in the first surface of the flow directing body for conducting fluids flowing through the flow directing body. The flow channel includes a channel surface set in from the first surface. A swirl bore extends though the flow directing body from the channel surface to the second surface of the flow directing body at an oblique angle relative to the channel surface for imparting a tangential swirl component onto fluids flowing through the swirl bore. Having an asymmetrical terminus portion of the channel surface, and positioning of the swirl bore within the terminus portion, allow control of the swirl direction for flow within the terminus portion and swirl bore.

Abstract: A lean direct injection fuel nozzle for a gas turbine is disclosed which includes a radially outer main fuel delivery system including a main inner air swirler defined in part by a main inner air passage having a radially inner wall with a diverging downstream surface, an intermediate air swirler radially inward of the main inner air swirler for providing a cooling air flow along the downstream surface of the radially inner wall of the main inner air passage, and a radially inner pilot fuel delivery system radially inward of the intermediate air swirler.

Abstract: An air-blast fuel injector is disclosed which includes an outer air circuit having an exit portion, an inner air circuit having an outlet configured to direct air toward the exit portion of the outer air circuit, and a fuel circuit radially outboard of the inner air circuit and having an exit communicating with the outer air circuit upstream from the exit portion of the outer air circuit.

Abstract: An air-blast fuel injector is disclosed which includes an outer air circuit having an exit portion, an inner air circuit having an outlet configured to direct air toward the exit portion of the outer air circuit, and a fuel circuit radially outboard of the inner air circuit and having an exit communicating with the outer air circuit upstream from the exit portion of the outer air circuit.

Abstract: An injector includes a main nozzle body defining a central axis and having a main fuel circuit. A pilot nozzle body is mounted inboard of the main nozzle body. The pilot nozzle body includes a pilot air circuit on the central axis with fuel circuitry radially outboard of the pilot air circuit for delivering fuel to a fuel outlet in a downstream portion of the pilot nozzle body. The fuel circuitry includes a primary pilot fuel circuit configured and adapted to deliver fuel to the fuel outlet and a secondary pilot fuel circuit configured and adapted to deliver fuel to the same fuel outlet.