Abstract: Bladed Gas Turbine Engine (GTE) rotors including deposited transition rings are provided, as are embodiments of methods for manufacturing bladed GTE rotors. In one embodiment, the method includes providing an outer blade ring having an inner circumferential surface defining a central opening, and depositing a deposited transition ring on the inner circumferential surface of the outer blade ring. The outer blade ring can be a full bladed ring or an annular grouping of individually-fabricated bladed pieces. After deposition of the transition ring, a hub disk is inserted into the central opening such that the transition ring extends around an outer circumferential surface of the hub disk. The transition ring is then bonded to the outer circumferential surface of the hub disk utilizing, for example, a hot isostatic pressing technique to join the transition ring and the outer blade ring thereto.

Abstract: Dual alloy turbine rotors and methods for manufacturing the same are provided. The dual alloy turbine rotor comprises an assembled blade ring and a hub bonded to the assembled blade ring. The assembled blade ring comprises a first alloy selected from the group consisting of a single crystal alloy, a directionally solidified alloy, or an equi-axed alloy. The hub comprises a second alloy. The method comprises positioning a hub within a blade ring to define an interface between the hub and the blade ring. The interface is a non-contacting interface or a contacting interface. The interface is enclosed by a pair of diaphragms. The interface is vacuum sealed. The blade ring is bonded to the hub after the vacuum sealing step.

Abstract: A turbine blade and a radial turbine having at least one blade is provided. The turbine blade includes a trailing edge and a leading edge opposite the trailing edge. The turbine blade also includes a cooling passage defined internally within the turbine blade. The cooling passage is in fluid communication with a source of cooling fluid via a single inlet to receive a cooling fluid. The cooling passage diverges at a first point downstream from the single inlet into at least two branches that extend along the at least one blade from the first point to a second point near a tip of the leading edge and the cooling passage converges at the second point.

Abstract: Dual alloy turbine rotors and methods for manufacturing the same are provided. The dual alloy turbine rotor comprises an assembled blade ring and a hub bonded to the assembled blade ring. The assembled blade ring comprises a first alloy selected from the group consisting of a single crystal alloy, a directionally solidified alloy, or an equi-axed alloy. The hub comprises a second alloy. The method comprises positioning a hub within a blade ring to define an interface between the hub and the blade ring. The interface is a non-contacting interface or a contacting interface. The interface is enclosed by a pair of diaphragms. The interface is vacuum sealed. The blade ring is bonded to the hub after the vacuum sealing step.

Abstract: Embodiments of an axially-split radial turbine, as are embodiments of a method for manufacturing an axially-split radial turbine. In one embodiment, the method includes the steps of joining a forward bladed ring to a forward disk to produce a forward turbine rotor, fabricating an aft turbine rotor, and disposing the forward turbine rotor and the aft turbine rotor in an axially-abutting, rotationally-fixed relationship to produce the axially-split radial turbine.

Abstract: Dual alloy bladed rotors are provided, as are methods for manufacturing dual alloy bladed rotors. In one embodiment, the method includes arranging bladed pieces in a ring formation such that contiguous bladed pieces contact along shank-to-shank bonding interfaces. The ring formation is positioned around a hub disk, which is contacted by the bladed pieces along a shank-to-hub bonding interface. A metallic sealing material is deposited between contiguous bladed pieces utilizing, for example, a laser welding process to produce an annular seal around the ring formation. A hermetic cavity is then formed, which is circumferentially bounded by the annular seal and which encloses the shank-to-shank and shank-to-hub bonding interface. Afterwards, a Hot Isostatic Pressing process is performed during which the ring formation and the hub disk are exposed to elevated pressures external to the hermetic cavity sufficient to diffusion bond the shank-to-shank and shank-to-hub bonding interface.

Abstract: Compliant coupling systems and methods are provided for coupling a shroud to an engine casing. The complaint coupling system includes a retaining ring adapted to be positioned adjacent to the shroud and adapted to be coupled to the engine casing. The retaining ring defines a coupling channel about a circumference of the retaining ring and at least one notch that interrupts the coupling channel. The complaint coupling system also includes a first clip received within the coupling channel. The first clip has a biasing portion that extends into a space defined by the at least one notch, and the biasing portion is adapted to contact the shroud. The complaint coupling system includes a second clip received within the coupling channel.

Abstract: Dual alloy Gas Turbine Engine (GTE) rotors and method for producing GTE rotors are provided. In one embodiment, the method include includes arranging bladed pieces in an annular grouping or ring formation such that shank-to-shank junctions are formed between circumferentially-adjacent bladed pieces. A first or bonding alloy is deposited along the shank-to-shank junctions utilizing a localized fusion deposition process to produce a plurality of alloy-filled joints, which join the bladed pieces in a bonded blade ring. The bonding alloy is preferably selected to have a ductility higher than and a melt point lower than the alloy from which the bladed pieces are produced. After deposition of the first alloy and formation of the alloy-filled joints, a hub disk is inserted into the central opening of the bonded blade ring. The hub disk and blade ring are then bonded utilizing, for example, a Hot Isostatic Pressing process.

Abstract: Bladed Gas Turbine Engine (GTE) rotors including deposited transition rings are provided, as are embodiments of methods for manufacturing bladed GTE rotors. In one embodiment, the method includes providing an outer blade ring having an inner circumferential surface defining a central opening, and depositing a deposited transition ring on the inner circumferential surface of the outer blade ring. The outer blade ring can be a full bladed ring or an annular grouping of individually-fabricated bladed pieces. After deposition of the transition ring, a hub disk is inserted into the central opening such that the transition ring extends around an outer circumferential surface of the hub disk. The transition ring is then bonded to the outer circumferential surface of the hub disk utilizing, for example, a hot isostatic pressing technique to join the transition ring and the outer blade ring thereto.

Abstract: An integral turbine includes a forward hub section and an aft hub section. The forward hub section and the aft hub section are metallurgically coupled to one another along an annular interface that resides within a plane generally orthogonal to a rotational axis of the axially-split turbine. The turbine further includes an airfoil blade ring metallurgically coupled to a radial outer surface of the coupled forward and aft hub sections and an impingement cavity formed within an interior portion of the coupled forward and aft hub sections. The impingement cavity includes an interior surface that is positioned proximate to the radial outer surface of the coupled forward and aft hub sections. Further, an impingement cooling air flow impinges against the interior surface of the impingement cavity to provide convective and conductive cooling to the radial outer surface of the coupled forward and aft hub sections.

Abstract: Auxiliary power units and methods and systems for activation and deactivation of a load compressor therein are provided. Auxiliary power unit includes the load compressor having an impeller, APU engine, coupling member, pre-spinning means, and APU controller. APU engine is adapted to be mechanically engaged to load compressor to drive load compressor to provide pneumatic power and to be disengaged when the need for pneumatic power ceases. Coupling member couples load compressor and APU engine and is configured to be controllably moved between an engaged position in which the APU engine is mechanically engaged with the load compressor, and a disengaged position, in which the APU engine is disengaged from the load compressor. APU controller is operably coupled to load compressor, APU engine, coupling member, and pre-spinning means and adapted to receive and be responsive to rotational speed signals for controlling movement of coupling member between engaged and disengaged positions.

Abstract: Dual alloy turbine rotors and methods for manufacturing the same are provided. The dual alloy turbine rotor comprises an assembled blade ring and a hub bonded to the assembled blade ring. The assembled blade ring comprises a first alloy selected from the group consisting of a single crystal alloy, a directionally solidified alloy, or an equi-axed alloy. The hub comprises a second alloy. The method comprises positioning a hub within a blade ring to define an interface between the hub and the blade ring. The interface is a non-contacting interface or a contacting interface. The interface is enclosed by a pair of diaphragms. The interface is vacuum sealed. The blade ring is bonded to the hub after the vacuum sealing step.

Abstract: Embodiments of an axially-split radial turbine, as are embodiments of a method for manufacturing an axially-split radial turbine. In one embodiment, the method includes the steps of joining a forward bladed ring to a forward disk to produce a forward turbine rotor, fabricating an aft turbine rotor, and disposing the forward turbine rotor and the aft turbine rotor in an axially-abutting, rotationally-fixed relationship to produce the axially-split radial turbine.

Abstract: An axially-split radial turbine includes a forward rotor section and an aft rotor section being mechanically and abuttingly coupled to one another along an annular interface that resides within a plane generally orthogonal to a rotational axis of the axially-split radial turbine. The axially-split radial turbine can be provided as part of a gas turbine engine.

Abstract: Embodiments of an axially-split radial turbine, as are embodiments of a method for manufacturing an axially-split radial turbine. In one embodiment, the method includes the steps of joining a forward bladed ring to a forward disk to produce a forward turbine rotor, fabricating an aft turbine rotor, and disposing the forward turbine rotor and the aft turbine rotor in an axially-abutting, rotationally-fixed relationship to produce the axially-split radial turbine.

Abstract: Embodiments of a gas turbine engine cooling system for deployment within a gas turbine engine are provided, as are embodiment of a method for producing a gas turbine engine cooling system. In one embodiment, the gas turbine engine cooling system includes an impeller having a hub, a plurality of hub bleed air passages, and a central bleed air conduit. The plurality of hub bleed air passages each have an inlet formed in an outer circumferential surface of the hub and an outlet formed in an inner circumferential surface of the hub. The central bleed air conduit is fluidly coupled to the outlets of the plurality of hub bleed air passages and is configured to conduct bleed air discharged by the plurality of hub bleed air passages to a section of the gas turbine engine downstream of the impeller to provide cooling air thereto.

Abstract: Auxiliary power units and methods and systems for activation and deactivation of a load compressor therein are provided. Auxiliary power unit includes the load compressor having an impeller, APU engine, coupling member, pre-spinning means, and APU controller. APU engine is adapted to be mechanically engaged to load compressor to drive load compressor to provide pneumatic power and to be disengaged when the need for pneumatic power ceases. Coupling member couples load compressor and APU engine and is configured to be controllably moved between an engaged position in which the APU engine is mechanically engaged with the load compressor, and a disengaged position, in which the APU engine is disengaged from the load compressor. APU controller is operably coupled to load compressor, APU engine, coupling member, and pre-spinning means and adapted to receive and be responsive to rotational speed signals for controlling movement of coupling member between engaged and disengaged positions.

Abstract: A flow discouraging system includes a stator assembly, a rotor assembly, and a plurality of fingers. The stator assembly includes one or more stationary components forming a side wall, the side wall including an annular groove defined by an outer axially-extending surface, an inner axially-extending surface, and a radial surface extending between the outer and inner axially-extending surfaces. The rotor assembly is disposed adjacent to and spaced apart from the stator assembly to form a portion of a cavity and includes an annular rim extending at least partially into the annular groove. The plurality of fingers is disposed in the annular groove and extends from the one or more stationary components the annular rim.

Abstract: An axially-split radial turbine includes a forward rotor section and an aft rotor section being mechanically and abuttingly coupled to one another along an annular interface that resides within a plane generally orthogonal to a rotational axis of the axially-split radial turbine. The axially-split radial turbine can be provided as part of a gas turbine engine.

Abstract: Embodiments of an axially-split radial turbine, as are embodiments of a method for manufacturing an axially-split radial turbine. In one embodiment, the method includes the steps of joining a forward bladed ring to a forward disk to produce a forward turbine rotor, fabricating an aft turbine rotor, and disposing the forward turbine rotor and the aft turbine rotor in an axially-abutting, rotationally-fixed relationship to produce the axially-split radial turbine.