Abstract: A gas turbine engine includes a compressor section and a combustion section with a scroll, a scroll baffle, a combustor, and a combustor case. The scroll defines an interior scroll flow path. The scroll baffle surrounds the scroll to define a scroll cooling passage. The combustor case surrounds the combustor and the scroll baffle to define a collector space. Moreover, the engine includes a turbine section with a turbine rotor and a turbine rotor blade shroud that includes a shroud cooling passage. The compressor flow path is fluidly connected to the scroll for cooling the scroll. Also, the scroll cooling passage is fluidly connected to the shroud cooling passage for cooling the turbine rotor blade shroud. Furthermore, the shroud cooling passage is fluidly connected to the collector space. Flow from the collector space flows into the combustor, along the interior scroll flow path, toward the turbine rotor.

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: A rotating machine includes a hub portion, wherein the hub portion comprises a forward face and an aft face. The rotating machine further includes a cooling channel formed on either the forward face or the aft face and configured to direct cooling air to a location on the rotating machine, wherein the cooling channel extends from a radially inner location along the face to a radially outer location along the face, and wherein the cooling channel is configured as a recess formed into an outer surface of the face.

Abstract: Methods for manufacturing a turbine nozzle are provided. A plurality of nozzle segments is formed. Each nozzle segment comprises an endwall ring portion with at least one vane. The plurality of nozzle segments are connected to an annular endwall forming a segmented annular endwall concentric to the annular endwall with the at least one vane of each nozzle segment extending between the segmented annular endwall and the annular endwall.

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: Methods for processing bonded dual alloy rotors are provided. In one embodiment, the method includes obtaining a bonded dual alloy rotor including rotor blades bonded to a hub disk. The rotor blades and hub disk are composed of different alloys. A minimum processing temperature (TDISK_PROCESS_MIN) for the hub disk and a maximum critical temperature for the rotor blades (TBLADE_MAX) is established such that TBLADE_MAX is less than TDISK_PROCESS_MIN. A differential heat treatment process is then performed during which the hub disk is heated to processing temperatures equal to or greater than TDISK_PROCESS_MIN, while at least a volumetric majority of each of the rotor blades is maintained at temperatures below TBLADE_MAX. Such a targeted differential heat treatment process enables desired metallurgical properties (e.g., precipitate hardening) to be created within the hub disk, while preserving the high temperature properties of the rotor blades and any blade coating present thereon.

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: A turbine rotor blade is provided. The turbine rotor blade includes a root, a platform coupled to the root, and an airfoil extending from the platform. The platform has a leading edge, a trailing edge, a suction side edge, and a pressure side edge. The pressure side edge includes a first concave portion.

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: 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: Embodiments of a gas turbine engine component having sealed stress relief slots are provided, as are embodiments of a gas turbine engine containing such a component and embodiments of a method for fabricating such a component. In one embodiment, the gas turbine engine includes a core gas flow path, a secondary cooling flow path, and a turbine nozzle or other gas turbine engine component. The component includes, in turn, a component body through which the core gas flow path extends, a radially-extending wall projecting from the component body and into the secondary cooling flow path, and one or more stress relief slots formed in the radially-extending wall. The stress relief slots are filled with a high temperature sealing material, which impedes leakage between the second cooling and core gas flow paths and which fractures to alleviate thermomechanical stress within the radially-extending wall during operation of the gas turbine engine.

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: A rotating machine includes a hub portion, wherein the hub portion comprises a forward face and an aft face. The rotating machine further includes a cooling channel formed on either the forward face or the aft face and configured to direct cooling air to a location on the rotating machine, wherein the cooling channel extends from a radially inner location along said face to a radially outer location along said face, and wherein the cooling channel is configured as a recess formed into an outer surface of said face.

Abstract: Methods are provided for manufacturing a shrouded bonded turbine rotor. A shrouded blade ring is formed. The shrouded blade ring is formed by bonding a unitary shroud ring to an assembled blade ring or assembling a plurality of shrouded turbine blade segments. The shrouded blade ring is bonded to a hub. The shrouded bonded turbine rotors are also provided. The shrouded bonded turbine rotor comprises a shrouded blade ring and a shroud. The shrouded blade ring comprises a plurality of turbine blade segments and a shroud. Each turbine blade segment comprises an airfoil portion including an airfoil having a root and a tip. The shroud covers the tip of each airfoil in the shrouded blade ring. A hub is bonded with the shrouded blade ring.

Abstract: Methods for manufacturing a turbine nozzle are provided. A plurality of nozzle segments is formed. Each nozzle segment comprises an endwall ring portion with at least one vane. The plurality of nozzle segments are connected to an annular endwall forming a segmented annular endwall concentric to the annular endwall with the at least one vane of each nozzle segment extending between the segmented annular endwall and the annular endwall.

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 a gas turbine engine component having sealed stress relief slots are provided, as are embodiments of a gas turbine engine containing such a component and embodiments of a method for fabricating such a component. In one embodiment, the gas turbine engine includes a core gas flow path, a secondary cooling flow path, and a turbine nozzle or other gas turbine engine component. The component includes, in turn, a component body through which the core gas flow path extends, a radially-extending wall projecting from the component body and into the secondary cooling flow path, and one or more stress relief slots formed in the radially-extending wall. The stress relief slots are filled with a high temperature sealing material, which impedes leakage between the second cooling and core gas flow paths and which fractures to alleviate thermomechanical stress within the radially-extending wall during operation of the 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.