Abstract: A coating system and method for reducing the tendency for hydrocarbon fluids, such as fuels and oils, to form carbonaceous deposits that adhere to a wall of a containment article. Of particular concern are carbonaceous deposits that form at temperatures below about 650° F. (about 345° C.). The coating system combines an outermost layer of platinum with a ceramic barrier layer. The coating system significantly reduces the formation of carbonaceous deposits and the adhesion of such deposits. To further reduce wall and hydrocarbon fluid temperatures and formation of carbonaceous deposits, the coating system is preferably applied to the surface of the wall wetted by the fluid, as well as the opposite surface of the wall exposed to a surrounding environment. The outermost layers serve as radiation shields to reduce heat transfer from the surrounding environment to the wall, and from the wall to the hydrocarbon fluid.

Abstract: An apparatus for actively controlling fuel flow from a fuel pump to a mixer assembly of a gas turbine engine combustor, where the mixer assembly includes a pilot mixer and a main mixer. The pilot mixer further includes an annular pilot housing having a hollow interior, a primary fuel injector mounted in the pilot housing and adapted for dispensing droplets of fuel to the hollow interior of the pilot housing, a plurality of axial swirlers positioned upstream from the primary fuel injector. The fuel flow control apparatus further includes: at least one sensor for detecting dynamic pressure in the combustor; a fuel nozzle; and, a system for controlling fuel flow supplied by the fuel nozzle through the valves. The fuel nozzle includes: a feed strip with a plurality of circuits for providing fuel to the pilot mixer and the main mixer; and, a plurality of valves associated with the fuel nozzle and in flow communication with the feed strip thereof.

Abstract: A multi-staged gas turbine engine fuel supply system includes a plurality of fuel injectors and at least first and second staged fuel injection circuits in each of the fuel injectors. Each of the first and second staged fuel injection circuits includes first and second fuel injection points and at least first and second fuel nozzle valves operable to open at different first and second crack open pressures and controllably connected to the first and second staged fuel injection circuits, respectively. A single fuel supply manifold is connected to all of the fuel nozzle valves. A single fuel signal manifold is controllably connected to all of the first and second fuel nozzle valves. The fuel injector may have a valve housing with one of the first fuel nozzle valves and one of the second fuel nozzle valves contained therein.

Abstract: A fuel injector includes an annular main fuel nozzle received within an annular nozzle housing, a main nozzle fuel circuit having at least one annular leg, and a pilot nozzle fuel circuit. Spray orifices of the leg extend through the fuel nozzle and spray wells through the housing are aligned with the orifices. The nozzle is designed to generate sufficient static pressure differentials between at least two different ones of the spray wells to purge the main nozzle fuel circuit. Spray well portions may be asymmetrically flared out with respect to a spray well centerline in different local streamwise directions. Some of the spray well portions may be asymmetrically flared out in a local upstream direction and others in a local downstream direction. The local streamwise direction may have an axial component parallel to a nozzle axis about which the annular nozzle housing is circumscribed and a circumferential component around the nozzle housing.

Abstract: A multi-staged gas turbine engine fuel supply fuel injector includes at least first and second staged fuel injection circuits having first and second fuel injection points. At least first and second fuel nozzle valves operable to open at different first and second crack open pressures are controllably connected to the first and second staged fuel injection circuits, respectively. A single fuel supply manifold is connected to all of the fuel nozzle valves. A single fuel signal manifold is controllably connected to all of the first and second fuel nozzle valves. The fuel injector includes a valve housing containing the fuel nozzle valves.

Abstract: A fuel injector includes a main fuel nozzle with a main nozzle fuel circuit and a pilot nozzle fuel circuit in fuel supply communication with a pilot nozzle. The injector further includes a purge means for purging the main nozzle fuel circuit while the pilot nozzle fuel circuit supplies fuel to the pilot nozzle and a purge air cooling means for supplying a cooled portion of purge air to the main nozzle fuel circuit during purging. The cooled portion is cooled with fuel that flows through the pilot nozzle fuel circuit. The purge air cooling means may include a purge air cooling path in thermal conductive communication with the pilot nozzle fuel circuit and operable to flow the cooled portion therethrough to the main nozzle fuel circuit during purging. The purge air cooling path may be in thermal conductive communication with at least one annular pilot leg of the pilot nozzle fuel circuit.

Abstract: A fuel injector includes an annular nozzle housing circumscribed about a nozzle axis and an annular fuel nozzle circumscribed about the nozzle axis within the housing. The annular fuel nozzle has at least one main nozzle fuel circuit, a pilot nozzle fuel circuit, and spray orifices extending radially away from the main nozzle fuel circuit through the annular fuel nozzle. Spray wells extend radially through the nozzle housing and are aligned with the spray orifices. An asymmetric cyclone means is located radially outwardly of the housing for generating a swirling flow around the nozzle and an asymmetric static pressure differential around the housing. The asymmetric cyclone means may be a symmetrical radial inflow swirler circumscribed about a cyclone axis that is not collinear with the nozzle axis or may have a plurality of angled flow swirling elements angled with respect to and asymmetrically circumscribed about the cyclone axis.

Abstract: A fuel injector includes an annular nozzle housing circumscribed about a nozzle axis and an annular fuel nozzle circumscribed about the nozzle axis within the housing. The annular fuel nozzle has at least one main nozzle fuel circuit, a pilot nozzle fuel circuit, and spray orifices extending radially away from the main nozzle fuel circuit through the annular fuel nozzle. Spray wells extend radially through the nozzle housing and are aligned with the spray orifices. An asymmetric cyclone means is located radially outwardly of the housing for generating a swirling flow around the nozzle and an asymmetric static pressure differential around the housing. The asymmetric cyclone means may be a symmetrical radial inflow swirler circumscribed about a cyclone axis that is not collinear with the nozzle axis or may have a plurality of angled flow swirling elements angled with respect to and asymmetrically circumscribed about the cyclone axis.

Abstract: A coating system and method for reducing the tendency for hydrocarbon fluids, such as fuels and oils, to form carbonaceous deposits that adhere to the walls of a containment article. Of particular concern are carbonaceous deposits that form at temperatures below about 650° F. (about 345° C.). The coating system combines an outermost layer of platinum with a ceramic barrier layer. The coating system has been shown to significantly reduce the formation of carbonaceous deposits at temperatures between about 220° F. and 650° F. (about 105° C. to about 345° C.), as well as reduce the adhesion of such deposits. The platinum outermost layer also serves as a radiation shield to reduce heat transfer from the containment article to the hydrocarbon fluid. The outermost layer is preferably deposited as an extremely thin film by chemical vapor deposition. The barrier layer is deposited to a thickness sufficient to prevent interdiffusion of the platinum outermost layer with the containment wall.

Abstract: A fuel injector includes a main fuel nozzle with a main nozzle fuel circuit and a pilot nozzle fuel circuit in fuel supply communication with a pilot nozzle. The injector further includes a purge means for purging the main nozzle fuel circuit while the pilot nozzle fuel circuit supplies fuel to the pilot nozzle and a purge air cooling means for supplying a cooled portion of purge air to the main nozzle fuel circuit during purging. The cooled portion is cooled with fuel that flows through the pilot nozzle fuel circuit. The purge air cooling means may include a purge air cooling path in thermal conductive communication with the pilot nozzle fuel circuit and operable to flow the cooled portion therethrough to the main nozzle fuel circuit during purging. The purge air cooling path may be in thermal conductive communication with at least one annular pilot leg of the pilot nozzle fuel circuit.

Abstract: A fuel injector includes an annular main fuel nozzle received within an annular nozzle housing, a main nozzle fuel circuit having at least one annular leg, and a pilot nozzle fuel circuit. Spray orifices of the leg extend through the fuel nozzle and spray wells through the housing are aligned with the orifices. The nozzle is designed to generate sufficient static pressure differentials between at least two different ones of the spray wells to purge the main nozzle fuel circuit. Spray well portions may be asymmetrically flared out with respect to a spray well centerline in different local streamwise directions. Some of the spray well portions may be asymmetrically flared out in a local upstream direction and others in a local downstream direction. The local streamwise direction may have an axial component parallel to a nozzle axis about which the annular nozzle housing is circumscribed and a circumferential component around the nozzle housing.

Abstract: A gas turbine engine fuel injector conduit includes a single feed strip having a single bonded together pair of lengthwise extending plates. Each of the plates has a single row of widthwise spaced apart and lengthwise extending parallel grooves. Opposing grooves in each of the plates are aligned forming internal fuel flow passages through the strip from an inlet end to an outlet end. The feed strip includes a substantially straight middle portion between the inlet end and the outlet end. In one alternative, the middle portion has a radius of curvature greater than a length of the middle portion. The feed strip has at least one acute bend between the inlet end and the middle portion and a bend between the outlet end and the middle portion. The feed strip has fuel inlet holes in the inlet end connected to the internal fuel flow passages.

Abstract: A coating system and method for reducing the tendency for hydrocarbon fluids, such as fuels and oils, to form carbonaceous deposits that adhere to the walls of a containment article. Of particular concern are carbonaceous deposits that form at temperatures below about 650° F. (about 345° C.). The coating system combines an outermost layer of platinum with a ceramic barrier layer. The coating system has been shown to significantly reduce the formation of carbonaceous deposits at temperatures between about 220° F. and 650° F. (about 105° C. to about 345° C.), as well as reduce the adhesion of such deposits. The platinum outermost layer also serves as a radiation shield to reduce heat transfer from the containment article to the hydrocarbon fluid. The outermost layer is preferably deposited as an extremely thin film by chemical vapor deposition. The barrier layer is deposited to a thickness sufficient to prevent interdiffusion of the platinum outermost layer with the containment wall.

Abstract: A gas turbine engine fuel injector conduit includes a single feed strip having a single bonded together pair of lengthwise extending plates. Each of the plates has a single row of widthwise spaced apart and lengthwise extending parallel grooves. Opposing grooves in each of the plates are aligned forming internal fuel flow passages through the strip from an inlet end to an outlet end. The feed strip includes a substantially straight middle portion between the inlet end and the outlet end. In one alternative, the middle portion has a radius of curvature greater than a length of the middle portion. The feed strip has at least one acute bend between the inlet end and the middle portion and a bend between the outlet end and the middle portion. The feed strip has fuel inlet holes in the inlet end connected to the internal fuel flow passages.