An engine can utilize a combustor to combust fuel to drive the engine. A fuel nozzle assembly can supply fuel to the combustor for combustion or ignition of the fuel. The fuel nozzle assembly can include a swirler and a fuel nozzle to supply a mixture of fuel and air for combustion, which can supply a primary fuel supply and a secondary fuel supply. Increasing efficiency and reducing emission require the use of alternative fuels, which combust at higher temperatures or burn at faster burn speeds than traditional fuels, requiring improved fuel introduction without the occurrence of flame holding or flashback.

A fuel supply system for an aircraft engine, comprises a gaseous fuel source and a fuel nozzle. The fuel nozzle includes a housing having a housing interior chamber and a fuel swirler disposed inside the housing interior chamber. The fuel swirler is fluidly connected to the gaseous fuel source for directing gaseous fuel to a combustor of the aircraft engine. The fuel swirler defines a gaseous fuel path extending from a fuel inlet to a fuel outlet. The gaseous fuel path includes a plurality of discrete apertures distributed around a circumference of the fuel swirler, each of the plurality of discrete apertures having a cross-sectional area selected to prevent a flame from propagating in an upstream direction through the gaseous fuel path towards the gaseous fuel source.

A fuel injector for a gas turbine engine of an aircraft having a fuel nozzle including a fuel swirler and/or an outer air swirler. The fuel swirler may include a manifold for receiving fuel from a fuel conduit, and a plurality of fuel passages to direct fuel from the manifold to discharge orifices that direct fuel with swirling flow. The fuel swirler may be configured to provide uniform spray while minimizing recirculation zones; reduce residence time as fuel enters the manifold; minimize flow disruptions, boundary layer growth, and/or pressure drop as fuel flows through the fuel passages; reduces coking internally of the nozzle; reduces thermal stresses; and is simple and low-cost to manufacture. The outer air swirler may include first and second outer air swirler portions with respective vanes and air passages that provide swirling air flow. The outer air swirler may be configured to improve atomization and spray uniformity with a wide spray angle; and minimize flow disruptions for enhancing flow performance.

A fuel supply system for a gas turbine engine comprises a housing having a housing interior chamber and a fuel swirler disposed inside the housing interior chamber. The fuel swirler has an upstream end and downstream end relative to a fuel flow direction along a fuel nozzle longitudinal axis. The fuel swirler has a first axial fuel passage along the longitudinal axis in fluid communication with a first fuel supply and terminating at a first fuel outlet at the downstream end, a second axial fuel passage along the longitudinal axis in fluid communication with a second fuel supply and terminating at a second fuel outlet at the downstream end, and a plurality of compressed air outlets at the downstream end. The first fuel outlet is positioned on an outermost surface of the fuel swirler and leads directly to a mixing site downstream of the fuel swirler.

A fuel supply device includes: an outer tubular member; an inner tubular member inside the outer tubular member; and a flow distribution portion on an inner surface of the outer tubular member or an outer surface of the inner tubular member, wherein the flow distribution portion includes first and second distribution wall portions arranged apart from one another in an axial direction of the inner tubular member, the first distribution wall portion includes first individual wall portions spaced apart from one another along a first circumference of the inner tubular member, the second distribution wall portion includes second individual wall portions spaced apart from one another along a second circumference of the inner tubular member, at least some of the first individual wall portions are arranged to face spaces between at least some of the second individual wall portions, respectively, in the axial direction of the inner tubular member.

A fuel injection nozzle for a combustion turbine engine has thermal stress-relief vanes, which accommodate and relieve localized thermal stresses within its monolithic, three-dimensional nozzle structure, imparted by heat transfer during engine combustion. At least one first vane is coupled to opposing, spaced nozzle sleeves at both ends. At least one cantilever-like second vane is coupled to one of the opposing sleeves on one end, while the other free or floating end is spaced by a second vane gap from the other opposing sleeve. Some embodiments include a plurality of second vanes, which have locally varying orientation, and/or structure, and/or second vane gaps, for normalizing spatially and/or temporally thermal stresses within the nozzle structure. The monolithic structure is fabricated, in some nozzle embodiments, by additive manufacturing.

A fuel spray nozzle including a primary atomizer to discharge a flow of swirled atomised fuel along and around a fuel spray nozzle axis. The primary atomiser includes outer air swirler disposed radially outwardly of a fuel pre-filmer channel. A secondary atomiser disposed around the primary atomiser includes secondary inner air swirler to swirl flow along an inner air channel. The secondary inner air swirler disposed radially inwardly of a secondary fuel pre-filmer channel of the secondary atomiser. A primary outer air channel defined between the primary outer swirler and the secondary inner swirler. The secondary inner air swirler include splitter wall to separate swirling flow in the secondary inner channel from the primary flow of atomised fuel. The secondary inner air swirler includes primary cap wall integral with and extending radially inwardly from the splitter wall to direct flow from the primary outer channel inwardly towards the fuel spray.

A fuel injector for an aircraft gas turbine engine includes a housing stem, a fuel nozzle coupled to the housing stem, and a fuel conduit extending through the housing stem and into the fuel nozzle where the fuel conduit bends to extend in a longitudinal downstream direction within the fuel nozzle. The fuel conduit is configured to transport bulk fuel flow further along the nozzle before being split downstream in the fuel circuit for final spray distribution, thereby promoting lower fuel temperatures. The fuel nozzle may minimize metal-to-metal contact between an external wall of the nozzle in thermal communication with ambient environment and an internal portion of the nozzle in thermal communication with the fuel circuit to minimize heat pick-up in the fuel. The fuel conduit may include a coiled section within a cavity of the fuel nozzle for compensating for thermal growth mismatches of the fuel injector.

A fuel injection device (70) includes a nozzle body (72) and a stem portion (110) connected to the rear end of the nozzle body at an angle. The stem portion is provided at a free end thereof with an annular wall member (128) defining a recess that receives the rear end of the nozzle body. The stem portion is covered by a heat insulating sleeve (122), and a part of the heat insulating sleeve adjacent to the free end of the stem portion is provided with a cutout (122B) exposing a part of the outer circumferential surface (128A) of the annular wall member. The exposed part of the annular wall member is provided with a heat insulating groove (130) opening at an end surface (128B) of the annular wall member facing the nozzle body.

A lean burn fuel injector has a head which has a coaxial arrangement of an inner pilot air-blast fuel injector and an outer main air-blast fuel injector. The pilot fuel injector comprises coaxially arranged inner and outer air swirler passages. The main fuel injector comprises coaxially arranged inner and outer air swirler passages. A first splitter is arranged between the passages. The first splitter has a conical divergent downstream portion. A second splitter is arranged radially within and spaced from the first splitter. The second splitter has a conical convergent portion and a conical divergent downstream portion. The downstream end of the second splitter is upstream of the downstream end of the first splitter. A connecting member connects the downstream end of the second splitter and the downstream portion of the first splitter upstream of the downstream end of the first splitter to form a sharp edge.