Abstract: An electrical discharge machining (EDM) apparatus includes a single workpiece fixture for holding a workpiece and a plurality of machining heads for machining different features into the workpiece. For example, a first machining head is arranged to machine a first feature into the workpiece, and a second machining head is arranged to machine a second feature into the workpiece. Each machining head is connected to a separate control system so as to operate independently.

Abstract: Air collecting manifold for a gas turbine engine including a plurality of arcuate pipe segments surrounding a compressor casing receives air from a system of feed tubes incorporating spherical ball joints to allow for differential thermal growth and limit transmission of vibration from one component of the manifold structure to another.

Abstract: A fuel delivery system and method for operating a dual fuel and steam turbine engine that utilizes gas fuel at the engine start phase through a combination of gas and liquid fuel circuits. Gas fuel initially flows through the liquid fuel circuits to a dual fuel and steam nozzle. A boiler connected to the system generates steam, and the steam is supplied to the nozzle to raise the fuel pressure to an acceptable range. The gas fuel is injected into both the liquid and gas fuel circuits and the engine can then operate on either gas or liquid fuel, or any combination thereof.

Abstract: A mixer for use in a combustion chamber of a gas turbine engine. The mixer includes a first fuel injector adapted for dispensing droplets of fuel during ignition and low power settings of the engine and a pilot swirler positioned upstream from the first fuel injector. The pilot swirler has a plurality of vanes for swirling air to mix air and the droplets of fuel. The mixer also includes a second fuel injector adapted for dispensing droplets of fuel during high power settings of the engine and a main swirler adjacent the pilot swirler and upstream from the second fuel injector. The main swirler has a plurality of vanes for swirling air traveling through the main swirler to mix air and the droplets of fuel dispensed by the second fuel injector. The mixer also includes a barrier positioned between the pilot swirler and main swirler for separating the first fuel injector from the second fuel injector.

Abstract: A cooling hole configuration for an air-cooled component, such as a gas turbine engine airfoil. The cooling hole is configured to have cross-sectional variations and a noncircular-shaped diffuser-type opening that significantly improve the cooling film distribution across the external surface of an airfoil, with the result that heat transfer from the surrounding environment to the airfoil is reduced. The cooling hole is configured to have its central axis at an acute angle to the exterior surface of the airfoil, and defines a noncircular-shaped opening at the airfoil surface. The cooling hole generally has a first region adjacent the airfoil surface and a second region interior to the airfoil.

Abstract: A method is provided for treating cooperating, juxtaposed substantially uncoated alloy substrate surfaces in preparation for brazing, for example an inner wall of the radially outer open end of a turbine engine blading member with the rim of an end plate or tip cap. The method includes treating at least one of the cooperating surfaces with a reducing gas comprising halogen gas for a time and at a temperature, for example 1-6 hours at 1650-1950° F., sufficient to remove any surface debris, for example oxides, and to deplete the alloy substrate surface of the total of elements selected from Al and Ti to a level of less than about 1 weight %. Depletion is to a depth in the surface which avoids intergranular attack of the substrate alloy surface. For example, the depth is no greater than about 0.0015″. Then the cooperating surfaces are brazed together.

Abstract: A fan blade includes a metal airfoil having a pocket disposed in a first side thereof, with the pocket including a filler bonded thereto. The pocket includes a plurality of cells separated by corresponding ribs which are submerged in the filler.

Abstract: An article comprising an airfoil surface is provided with a thermal insulating outer layer on at least one region, but not all, of the airfoil surface. The region is selected from the airfoil surface which has been observed to experience more strenuous environmental operating conditions during service operation than the airfoil surface outside of the region. In one form, the thermal insulating outer layer is applied to at least one region of each of a plurality of airfoil surfaces. Each airfoil surface is disposed about an axis of rotation with the region of each airfoil surface facing generally outwardly from the axis of rotation and from each other. The airfoil surfaces are rotated about the axis of rotation while a thermal insulating material contacts at least the regions.

Abstract: A mixer assembly for use in a combustion chamber of a gas turbine engine. The assembly includes a pilot mixer and a main mixer. The pilot mixer includes an annular pilot housing having a hollow interior, a pilot fuel nozzle mounted in the housing and adapted for dispensing droplets of fuel to the hollow interior of the pilot housing, and one or more axial swirlers positioned upstream from the pilot fuel nozzle. The main mixer includes a main housing surrounding the pilot housing and defining an annular cavity, an annular fuel injector having a plurality of fuel injection ports arranged in a circular pattern surrounding the pilot housing and mounted inside the annular cavity of the main mixer for releasing droplets of fuel into swirling air downstream from the fuel injector, and one or more axial swirlers positioned upstream from the plurality of fuel injection ports.

Abstract: A fan case for a turbofan engine having a fan including plurality of fan blades mounted to a rotor disk and a decoupler that fails in response to a predetermined load includes a substantially annular shell. The shell has a forward section, an intermediate section, and an aft section. The fan case further includes an aft facing step formed at the forward end of the intermediate section to prevent blade fragments from being ejected forward. The intermediate section is axially aligned with the fan and has a large inside diameter. The intermediate section thus defines an annular space around the fan blades that is sufficiently large to allow the fan to orbit when the decoupler fails. The intermediate section and the aft section are aligned radially to allow blade fragments to be ejected aft, avoiding additional secondary blade damage.

Abstract: A gas turbine engine includes a compressor rotor assembly which directs air at a sufficent pressure and temperature to a compressor rotor bore. The compressor assembly includes a compressor including a plurality of rotors joined with a plurality of couplings. Each of the rotors includes a radially outer rim, a radially inner hub, and a web extending therebetween. The web includes a flange including a plurality of slots which define a plurality of radial vanes that are airfoil-shaped. The vanes effectively deswirl bleed air and re-direct the airflow to a compressor bore.

Abstract: A gas turbine engine exhaust nozzle includes an exhaust duct for channeling a gas jet. A plurality of adjoining chevrons are disposed at an aft end of the duct to define an exhaust outlet. Each of the chevrons is triangular in configuration, with a base, apex, side trailing edges converging therebetween, and radially opposite first and second surfaces bounded thereby. The trailing edges of adjacent chevrons are spaced laterally apart to define respective diverging slots disposed in flow communication with the duct. The chevrons have a concave contour axially between the bases and apexes which promotes jet mixing through the slots.

Abstract: A fuel injection assembly for a gas turbine engine combustor, including at least one fuel stem, a plurality of concentrically disposed tubes positioned within each fuel stem, wherein a cooling supply flow passage, a cooling return flow passage, and a tip fuel flow passage are defined thereby, and at least one fuel tip assembly connected to each fuel stem so as to be in flow communication with the flow passages, wherein an active cooling circuit for each fuel stem and fuel tip assembly is maintained by providing all active fuel through the cooling supply flow passage and the cooling return flow passage during each stage of combustor operation. The fuel flowing through the active cooling circuit is then collected so that a predetermined portion thereof is provided to the tip fuel flow passage for injection by the fuel tip assembly.

Abstract: An annular turbine frame includes a first ring such as a radially outer casing disposed coaxially about an axial centerline axis and having a plurality of circumferentially spaced apart first ports. A plurality of circumferentially spaced apart hollow struts are joined radially to the first ring by a corresponding plurality of collars. Each strut has radially opposite first and second ends, and a through channel extending therebetween. Each of the collars is disposed between a respective one of the strut first ends and the first ring in alignment with a respective one of the first ports for removably joining the struts to the first ring. Each of the collars includes a base disposed against the first ring and has a plurality of mounting holes for receiving mounting bolts therethrough to removably join the base to the first ring. The base has a central aperture aligned with the first port. Each collar mounting hole has a hole counterbore through a radially outer portion of the collar mounting hole.

Abstract: Increased impact resistance capability is achieved in a cost and weight efficient manner by providing a spinner made of a 3-D orthogonal woven composite material. The spinner defines a generally conical shell having a plurality of axial rib stiffeners and at least one circumferential rib stiffener integrally formed thereon. The combination of the integral rib stiffeners with the 3-D orthogonal woven composite material results in a substantially greater torsional stiffness. The use of the 3-D orthogonal woven composite material also eliminates delamination found in laminated composite spinners.

Abstract: A fuel injection system for use with a gas turbine engine includes a plurality of thermally compatible fuel nozzles. Each fuel nozzle includes a delivery system to deliver a fluid supply to the gas turbine engine and a support system for supporting the delivery system. The delivery system is disposed within the support system and is subjected to lower operating temperatures than the support system. The delivery system is fabricated from a material having a coefficient of expansion approximately twice a coefficient of expansion for the material used in fabricating the support system.

Abstract: A double brush seal for sealing the combustor-turbine nozzle interface of a gas turbine engine includes a stationary support member and an intermediate plate attached to the stationary support member. The brush seal also includes a first end plate located upstream of the intermediate plate and attached to the stationary support member, and a second end plate located downstream of the intermediate plate and attached to the stationary support member. A first bristle pack is disposed between the first end plate and the intermediate plate, and a second bristle pack is disposed between the second end plate and the intermediate plate such that the intermediate plate functions as a common back plate for the two stages of the seal.

Abstract: A combustor includes a fuel injector for injecting fuel into the combustor, a baseline air blast pilot splitter including a converging downstream side and a splitter extension. The splitter extension includes a diverging upstream portion attached to a baseline air blast splitter, a diverging downstream portion, and a converging intermediate portion extending between the upstream portion and the downstream portion.

Abstract: A turbine engine blade damper for damping vibrations of blades in a turbine engine. The blade damper includes an elongate body extending between a forward end and a rearward end opposite the forward end. The body is sized and shaped for receipt within a gap formed between adjacent platforms of the blades so the body frictionally engages the adjacent platforms to dampen vibrations of the blades and to prevent air from passing through the corresponding gap during engine operation. The damper also includes a retainer mounted on at least one of the forward and rearward ends of the body. The retainer is sized and shaped for receipt within a recess formed in at least one of the adjacent blades to hold the body between the blades. The retainer is sized and shaped to prevent air from passing between the blades and the retainer during engine operation.

Abstract: A fuel injector for use in a gas turbine engine includes an inlet stem with a bore formed therein and an insert disposed in the bore. The insert has a cavity formed therein for receiving a fuel filter. The use of the insert allows the upstream end of the inlet stem to be connected to a fuel manifold with a double seal fitting.