Abstract: A deswirler system for a centrifugal compressor of a gas turbine engine that improves overall engine performance as a result of exhibiting significantly reduced friction losses. The deswirler system generally entails an annular-shaped manifold having an inlet configured to receive radially-outward flowing gas from a diffuser of the compressor, an outlet configured to discharge the gas in an axial downstream direction, and an arcuate passage therebetween. The deswirler system further includes a plurality of deswirler vanes directly within the arcuate passage and closely coupled to the diffuser.

Abstract: A combustor includes outer and inner liners joined at one end to an annular dome. A swirl cup is mounted to the dome and includes a flare cone extending therethrough. The flare cone has an obtuse flare angle for discharging fuel in a wide spray from an outlet of the cone. A flared beat shield surrounds the cone, and extends in part aft from the cone outlet, and is offset in part forwardly from the cone outlet to define a radially outwardly facing step.

Abstract: A tip cap hole is loaded with a first composition comprising particles of a first alloy having a solidus temperature above the brazing temperature. The first composition is covered with a second composition comprising particles of a second alloy having a liquidus temperature below the brazing temperature. The second composition is heated to the brazing temperature to cause particles of the second alloy to melt to form a liquid of the second alloy which is carried into spaces between the particles of the first alloy by capillarity. The liquid of the second alloy is cooled to form a solid securely bonding the particles of the first alloy. By weight, the second alloy has no more than 1% B and from 3% to 11% Si. The first alloy has Cr and at least about 5% Al, at least about 0.5% Hf, no more than 0.5% Ti.

Abstract: A method of removing a core from a CMC component in which the core was used to form an internal cavity. According to one embodiment of the invention, the core is removed from a fully densified CMC component by heating the component and core to a temperature at which the core deteriorates but below a temperature at which the component would melt or otherwise be damaged. According to a second embodiment of this invention, the component is only partially densified, and then impregnated with a coating material that is resistant to a leaching compound capable of removing the core. The core can then be removed using the leaching compound without damage to the internal surfaces of the component defined by the core when the component was fabricated.

Abstract: An article having a design external aerodynamic shape includes a body with a body external surface and an outer portion external surface of an outer portion bonded with a part of but less than substantially all of the body surface. The external surfaces of the body and outer portion each define less than the design external aerodynamic shape. However, together they define such shape. The article is made by selecting the design external aerodynamic shape from an existing article having a first body and a first outer portion. A replacement outer portion is selected in an amount less than the first outer portion and bonded with a region less than substantially all of a replacement body external surface. The replacement body has a replacement body external surface and replacement body external shape different from the first body substantially by that amount. The replacement body is made with the replacement body external shape.

Abstract: The surface of a workpiece is treated by discharging a stream of pliant shot in a carrier fluid at a shallow angle of incidence thereagainst. The shot is then scrubbed laterally along the surface for selectively removing target material therefrom.

Abstract: An article is formed of a gas turbine component having a substrate, an internal passage through the substrate defining an internal surface of the substrate, and an internal protective layer overlying the internal surface of the substrate. The internal protective layer has a composition of aluminum, plus, in weight percent, on average from about 0.1 to about 5.0 percent of a modifying element selected from the group consisting of hafnium, yttrium, zirconium, chromium, and silicon, and combinations thereof, and elements found in the substrate.

Abstract: An air-cooled airfoil whose surfaces adjacent its trailing edge are not equally cooled in order to compensate for unequal heating of the pressure and suction walls near the trailing edge. The airfoil is formed to have a cooling passage defined by and between the pressure and suction walls at the airfoil trailing edge. The interior surface of the suction wall is formed to be substantially smooth and uninterrupted, while the interior surface of the pressure wall is formed to include surface features that project into the cooling passage to cause preferential convective cooling of the pressure wall as compared to the suction wall when air flows through the cooling passage.

Abstract: A method for restoring a protective coating including a metallic environmental resistant coating of a coating total thickness within a coating design thickness range on a metal substrate of an article includes the application of a replacement material to at least one discrete local surface area on which an undesirable amount of degradation has occurred. Such degradation can extend through the protective coating into the metal substrate. The degradation product can include at least one of oxidation, coating rumpling, and coating voiding, for example, rumpling or voiding of a bond coat under a ceramic thermal barrier coating (TBC). The degradation product first is conditioned at the discrete local area to expose an underlying portion while retaining at least a portion of the metallic environmental coating on surface areas adjacent the discrete surface area. Then a replacement metallic environmental resistant material is applied, retaining the coating total thickness within the coating design thickness range.

Abstract: A turbine nozzle vane includes pressure and suction sidewalls extending between leading and trailing edges. The vane includes a pair of integral ribs defining three internal cooling channels between the leading and trailing edges. Rows of film cooling holes extend through the sidewalls, and three rows in the pressure side are inclined along the span of the airfoil at different slopes.

Abstract: An article and a method for improving an article that results in a reduction or elimination of damage due to fretting from contact of similar metals. The invention specifically reduces wear-related fretting between titanium alloy parts by lowering the stresses between mating parts. An aluminum bronze coating is applied to one of the parts. The aluminum bronze coating provides an improvement over prior art coatings in reducing coefficient of friction between the parts. Additionally, the cumulative stresses at the surface of the parts is reduced by a dual intensity peening treatment. This involves a first peening operation using large peening media that provides a compressive stress to the required depth. This first peening operation is followed by a second peening operation that provides additional compressive stresses closer to the dovetail surface.

Abstract: A combustor liner for use in a gas turbine engine includes a first annular panel section having a first cooling nugget formed at one end thereof and a second annular panel section having a second cooling nugget formed at one end thereof. A first row of cooling holes is formed in the first cooling nugget, and a second row of cooling holes is formed in the second cooling nugget. The second row of cooling holes is arranged in a preferential cooling pattern including a plurality of arrays, each array has a first set of cooling holes having a first diameter and a second set of cooling holes having a second diameter that is smaller than the first diameter. The cooling hole arrays are preferably arranged to minimize tooling set-ups and thereby reduce cost. At least one igniter tower is formed in the first annular panel section and is circumferentially aligned with one of the second sets of cooling holes.

Abstract: A multi-layer seal and washer that provide a seal between a vane stem and a casing in a turbine engine are disclosed. The seal and washer are fabricated from materials such as Teflon fibers and glass fibers and are impregnated with a polyimide resin. The seal and washer are durable and have a low coefficient of friction.

Abstract: An exhaust nozzle includes cascade vanes mounted in a duct for discharging exhaust. The vanes have a dolphin profile which is effective for turning subsonically the exhaust near leading edges of the vanes, and then diffusing supersonically the exhaust downstream therefrom. Thrust efficiency of the vanes is therefore shifted to lower pressure ratios during operation for improving performance of the nozzle.

Abstract: A combustor liner includes a row of primary dilution holes disposed aft of a forward end thereof, and a row of secondary dilution holes disposed between the primary holes and an aft end of the liner. The secondary holes vary in size circumferentially to a maximum size offset circumferentially from the primary holes.

Abstract: A method for preventing the deposition of material in an opening near a surface of an article, and a masking insert therefore. The method and insert are particularly suited for preventing the plating of a metal, such as platinum, on turbine airfoils or turbine blades and vanes having a complex geometry, as is the case when cast trailing edge cooling slots are present in the airfoil surface. The method entails the use of the masking insert, which is precisely configured to mask the cooling slots during plating by preventing circulation of the plating bath through the slots. For this purpose, the insert is equipped with appendages that are sized, shaped, spaced and oriented on a base member to register with, and preferably be received within, the cooling slots of an airfoil having a particular cooling slot design.

Abstract: An infrared suppressor system for a gas turbine engine is provided for suppressing infrared radiation associated with the hot metal parts of the engine and with the hot exhaust gases exhausted from the engine. The system features a unique arrangement of multiple baffles that are connected together as a single baffle module. The baffle arrangement permits mixing of hot and cool gas flows while eliminating line-of-sight infrared radiation in an axially compact suppressor. The baffles are additionally linked together into a single insertable baffle module that permits removal of the baffle module when infrared suppression is unnecessary.

Abstract: A gas turbine engine including in-line intercooling wherein compressor intercooling is achieved without removing the compressor main flow airstream from the compressor flowpath is described. In an exemplary embodiment, a gas turbine engine suitable for use in connection with in-line intercooling includes a low pressure compressor, a high pressure compressor, and a combustor. The engine also includes a high pressure turbine, a low pressure turbine, and a power turbine. For intercooling, fins are located in an exterior surface of the compressor struts in the compressor flowpath between the outlet of the low pressure compressor and the inlet of the high pressure compressor. Coolant flowpaths are provided in the compressor struts, and such flowpaths are in flow communication with a heat exchanger. In operation, air flows through the low pressure compressor, and compressed air is supplied from the low pressure compressor to the high pressure compressor.

Abstract: A thermal barrier coating system and a method for forming the coating system on an article. The coating system employs a bond coat of a nickel aluminide alloy over which a thermal-insulating ceramic layer is deposited. The nickel aluminide bond coat contains zirconium, but is otherwise predominantly of the beta (&bgr;) NiAl phase. The bond coat is preferably deposited by a physical vapor deposition process to have a fine-grain microstructure and a limited diffusion zone in the article surface.

Abstract: A gas turbine engine turbine blade shrouded tip has an airfoil tip with a cross-sectional airfoil shape, a blade tip shroud attached to the tip, and a shroud cooling circuit disposed within the blade tip shroud. The shroud cooling circuit is operable for cooling substantially all of the shroud and is in fluid communication with a hollow interior of the tip. One embodiment of the invention includes two circumferentially extending forward and aft seal teeth on a radially outer shroud surface of the shroud extending in a radial direction away from the hollow interior of the tip. The shroud cooling circuit includes circumferentially extending shroud cooling passages between clockwise and counter-clockwise shroud side edges of the shroud. Forward and aft pluralities of the shroud cooling passages within the tip shroud are in fluid communication with first and second cavities respectively in the hollow interior.