Abstract: A trailing edge vortex reducing system includes a gas turbine engine airfoil extending in a spanwise direction, one or more spanwise extending plasma generators in a trailing edge region around a trailing edge of the airfoil. The plasma generators may be mounted on an outer wall of the airfoil with first and second pluralities of the plasma generators on pressure and suction sides of the airfoil respectively. The plasma generators may include inner and outer electrodes separated by a dielectric material disposed within a grooves in an outer hot surface of the outer wall of the airfoil. The plasma generators may be located at an aft end of the airfoil and the inner electrodes flush with the trailing edge base. A method for operating the system includes energizing one or more of plasma generators in steady state or unsteady modes.

Abstract: A turbofan gas turbine engine includes a forward fan section with a row of fan rotor blades, a core engine, and a fan bypass duct downstream of the forward fan section and radially outwardly of the core engine. The forward fan section has only a single stage of variable fan guide vanes which are variable fan outlet guide vanes downstream of the forward fan rotor blades. An exemplary embodiment of the engine includes an afterburner downstream of the fan bypass duct between the core engine and an exhaust nozzle. The variable fan outlet guide vanes are operable to pivot from a nominal OGV position at take-off to an open OGV position at a high flight Mach Number which may be in a range of between about 2.5-4+. Struts extend radially across a radially inwardly curved portion of a flowpath of the engine between the forward fan section and the core engine.

Abstract: An axial flow positive displacement compressor has an inlet axially spaced apart and upstream from an outlet. Inner and outer bodies have offset inner and outer axes extend from the inlet to the outlet through first and second sections of a compressor assembly in serial downstream flow relationship. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes respectively. The inner and outer helical blades extend radially outwardly and inwardly respectively. The helical blades have first and second twist slopes in the first and second sections respectively. The first twist slopes are less than the second twist slopes. An engine including the compressor has in downstream serial flow relationship from the compressor a combustor and a high pressure turbine drivingly connected to the compressor by a high pressure shaft.

Abstract: A non-aircraft-propelling auxiliary gas turbine engine installable in an aircraft having a cabin adapted to be pressurized. The auxiliary gas turbine engine includes an auxiliary-gas-turbine-engine compressor having an inlet, wherein the inlet is adapted to receive pressurized air from the cabin. A method for operating a non-aircraft-propelling auxiliary gas turbine engine of an aircraft includes providing pressurized air from the cabin of the aircraft to an inlet of a compressor of the auxiliary gas turbine engine. The method includes providing compressed air from the compressor to a combustor of the auxiliary gas turbine engine and includes providing combustion gases from the combustor to a turbine of the auxiliary gas turbine engine, wherein the turbine is mechanically coupled to the compressor.

Abstract: An axial flow positive displacement engine has an inlet axially spaced apart and upstream from an outlet. Inner and outer bodies have offset inner and outer axes extend from the inlet to the outlet through first, second, and third sections of a core assembly in serial downstream flow relationship. At least one of the bodies is rotatable about its axis. The inner and outer bodies have intermeshed inner and outer helical blades wound about the inner and outer axes respectively. The inner and outer helical blades extend radially outwardly and inwardly respectively. The helical blades have first, second, and third twist slopes in the first, second, and third sections respectively. The first twist slopes are less than the second twist slopes and the third twist slopes are less than the second twist slopes. A combustor section extends axially downstream through at least a portion of the second section.

Abstract: An downstream plasma boundary layer shielding system includes film cooling apertures disposed through a wall having cold and hot surfaces and angled in a downstream direction from a cold surface of the wall to an outer hot surface of the wall. A plasma generator located downstream of the film cooling apertures is used for producing a plasma extending downstream over the film cooling apertures. Each plasma generator includes inner and outer electrodes separated by a dielectric material disposed within a groove in the outer hot surface. The wall may be part of a hollow airfoil or an annular combustor or exhaust liner. A method for operating the downstream plasma boundary layer shielding system includes forming a plasma extending in the downstream direction over the film cooling apertures along the outer hot surface of the wall. The method may further include operating the plasma generator in steady state or unsteady modes.

Abstract: A method of producing a CMC article having a net shape, and by which the article can be formed to have an exterior surface with desirable characteristics, such as being free of an imprint pattern of a fiber reinforcement material within the article. The method entails providing a body comprising the fiber reinforcement material, and depositing a coating on a surface of the body. The coating contains a carbonaceous binder and a slurry containing a ceramic particulate material. Following its deposition, the carbonaceous binder within the coating is cured to render the coating machinable, and the coating is then machined to approximately produce the net shape of the article.

Abstract: A protective coating for use on a silicon-containing substrate, and deposition methods therefor. The coating has a barium-strontium-aluminosilicate (BSAS) composition that is less susceptible to degradation by volatilization and in corrosive environments as a result of having at least an outer surface region that consists essentially of one or more stoichiometric crystalline phases of BSAS and is substantially free of a nonstoichiometric second crystalline phase of BSAS that contains a substoichiometric amount of silica. The coating can be produced by carrying out deposition and heat treatment steps that result in the entire coating or just the outer surface region of the coating consisting essentially of the stoichiometric celsian phase.

Abstract: A system for providing air to a compressor of an auxiliary gas turbine engine of an aircraft. A system turbine has an inlet adapted to receive compressed air from the aircraft. A system compressor is mechanically coupled to the system turbine and has an inlet adapted to receive atmospheric air. The outlets of the system turbine and the system compressor are fluidly connectable to the inlet of the compressor of the auxiliary gas turbine engine. A method includes providing compressed air from an aircraft to an inlet of a system turbine mechanically coupled to a system compressor. The method includes providing atmospheric air to an inlet of the system compressor. The method includes providing the inlet of the compressor of an auxiliary gas turbine engine with air from an outlet of the system turbine and with air from an outlet of the system compressor.

Abstract: An article comprising a turbine component other than an airfoil having a metal substrate and a ceramic corrosion resistant coating overlaying the metal substrate. This coating has a thickness up to about one micrometer and consists of a ceramic composition that comprises a ceramic metal oxide selected from the group consisting of zirconia, hafnia and mixtures thereof. This coating can be formed by alternative methods to have different microstructures, including a dense matrix or a strain-tolerant columnar grain structure.

Abstract: A process for brazing components formed of superalloys that contain elements prone to oxidation during brazing. At least one braze tape is applied to at least one faying surface of at least a first of the components being joined by brazing. The braze tape comprises a braze tape alloy containing the base metal of the superalloys and a melting point suppressant, and is applied so as to substantially cover the faying surface. The braze tape is then bonded to the faying surface by heating the first component to a temperature not exceeding the brazing temperature required to join the components. Thereafter, the components are assembled so that the bonded braze tape are between the respective faying surfaces of the components. The components are then brazed together by applying and heating a braze alloy to the braze temperature.

Abstract: A method and masking assembly for masking a dovetail portion of a turbine blade during coating of an airfoil portion of the blade. The masking assembly comprises at least two masking members, each having an exterior surface and an oppositely-disposed undulatory surface complementary to one of oppositely-disposed undulatory surfaces of the dovetail portion. By mating the masking members, the undulatory surfaces thereof define an interior cavity within the masking assembly that accommodates the dovetail portion, and the undulatory surfaces of the masking members contact the undulatory surfaces of the dovetail portion to entrap the dovetail portion within the interior cavity of the masking assembly.

Abstract: A leading edge vortex reducing system includes a gas turbine engine airfoil extending in a spanwise direction away from an end wall, one or more plasma generators extending in the spanwise direction through a fillet between the airfoil and the end wall in a leading edge region near and around a leading edge of the airfoil and near the fillet. The plasma generators being operable for producing a plasma extending over a portion of the fillet in the leading edge region. The plasma generators may be mounted on an outer wall of the airfoil with a first portion of the plasma generators on a pressure side of the airfoil and a second portion of the plasma generators on a suction side of the airfoil. A method for operating the system includes energizing one or more plasma generators to form the plasma in steady state or unsteady modes.

Abstract: A gas turbine engine has components including a compressor, a combustor, and a turbine. At least one component is radially bladed having at least one row of radially extending rotatable blades and at least another is a worm component having an inner body disposed within an outer body. The inner and outer bodies have offset inner and outer axes, intermeshed inner and outer helical blades wound about the inner and outer axes respectively, and at least one of the inner and outer bodies being rotatable about a corresponding one of the inner and outer axes. An aircraft gas turbine engine has components in serial downstream flow relationship including a fan, a low pressure compressor, a high pressure compressor, a combustor, a high pressure turbine, and a low pressure turbine. At least one of the components is radially bladed and at least one of the components is a worm component.

Abstract: A thermal barrier coating and deposition process for a component intended for use in a hostile thermal environment, such as the turbine, combustor and augmentor components of a gas turbine engine. The TBC has a first coating portion on at least a first surface portion of the component. The first coating portion is formed of a ceramic material to have at least an inner region, at least an outer region overlying the inner region, and a columnar microstructure whereby the inner and outer regions comprise columns of the ceramic material. The columns of the inner region are more closely spaced than the columns of the outer region so that the inner region of the first coating portion is denser than the outer region of the first coating portion, wherein the higher density of the inner region promotes the impact resistance of the first coating portion.

Abstract: A gas turbine engine thermal control apparatus includes at least one annular spray tube having spray holes oriented to impinge thermal control air onto a fillet between an outer casing and a forward thermal control ring and, in a more particular embodiment, into a center of the fillet. The apparatus may include an annular segmented stator shroud attached to the outer casing and circumscribing radial outer blade tips of turbine blades of a turbine rotor. A thermal air distribution manifold encircling a portion of the outer casing includes an annular supply tube connected in fluid supply relationship to plenums of header assemblies. The annular spray tube is connected to at least one of the plenums and may be elongated radially inwardly and axially. Baffles attached to radially outwardly facing surfaces of the panels may be contoured to form exhaust passages having exhaust passage inlets and outlets between the baffles and the panels.

Abstract: A gas turbine engine augmentor radial fuel spray bar has a counterswirling spray bar heat shield. Two embodiments of the heat shield include one with a cambered airfoil cross-section and another with a twisted airfoil cross-section and may have varying or constant degree of camber or twist, respectively, along a radial length of the spray bar heat shield. The spray bar may have one or more spray bar fuel tubes within the heat shield, openings in the heat shield, and fuel holes in the tubes operable for injecting fuel through the openings. A gas turbine engine augmentor having a plurality of circumferentially spaced apart radial flameholders may incorporate a plurality of the augmentor radial fuel spray bars with one or more of the augmentor radial fuel spray bars circumferentially disposed between one or more circumferentially adjacent pairs of the radial flameholders.

Abstract: An upstream plasma boundary layer shielding system includes film cooling apertures disposed through a wall having cold and hot surfaces and angled in a downstream direction from a cold surface of the wall to an outer hot surface of the wall. A plasma generator located upstream of the film cooling apertures is used for producing a plasma extending downstream over the film cooling apertures. Each plasma generator includes inner and outer electrodes separated by a dielectric material disposed within a groove in the outer hot surface. The wall may be part of a hollow airfoil or an annular combustor or exhaust liner. A method for operating the upstream plasma boundary layer shielding system includes forming a plasma extending in the downstream direction over the film cooling apertures along the outer hot surface of the wall. The method may further include operating the plasma generator in steady state or unsteady modes.

Abstract: A turbine airfoil having an improved impact and erosion resistance. The airfoil comprises: (a) a base segment having an impact resistant leading edge section proximate to the leading edge comprising a material having having a yield strength of least about 250 ksi and an elongation percentage of about 12% or less; and (b) an erosion resistant coating overlaying the base segment at least in the leading and trailing edge portions of the pressure side, the erosion resistant coating comprising at least one ceramic layer having at least one of the following properties: (1) an erosion value of at least about 200 g. of erodent to cause a thickness loss of about 15-20 microns; (2) an erosion volume loss value (V) of about 1.9 or less as defined by the equation V=H?0.18×E0.75×F?1.65 where H is hardness, E is elastic modulus and F is fracture toughness; and (3) an F value of at least about 1.5 MPa*m1/2.

Abstract: A swirler arrangement for a mixing assembly of a gas turbine engine combustor, where the swirler arrangement has a centerline axis therethrough, including: a swirler housing including an outer radial wall and an upstream wall; a first plurality of vanes incorporated into the outer radial wall, wherein the first plurality of vanes are oriented at a first angle with respect to an axis through the outer radial wall; and, a second plurality of vanes incorporated into the outer radial wall, wherein the second plurality of vanes are oriented at a second angle with respect to the through the outer radial wall. A first type of passage is defined between adjacent first and second vanes having a first configuration and a second type of passage is defined between adjacent first and second vanes having a second configuration so that air flowing through the swirler arrangement is swirled in a desirable manner.