Abstract: A turbine flowpath apparatus for a gas turbine engine includes: a flowpath component exposed at least partially to a primary combustion gas flowpath of the engine, the flowpath component comprising low-ductility material; a metallic annular stationary structure surrounding the flowpath component, including a bearing surface which bears against the flowpath component, so as to restrain the flowpath component from axial movement in a first direction; and a spring element disposed between the flowpath component and the stationary structure which resilient urges the flowpath component in the first direction against the bearing surface.

Abstract: A turbine shroud apparatus for a gas turbine engine includes: a plurality of arcuate shroud segments arranged as an annular shroud, each of the shroud segments comprising low-ductility material and having a cross-sectional shape defined by opposed forward and aft walls, and opposed inner and outer walls, the walls extending between opposed first and second end faces, wherein an open channel is formed through the outer wall of each shroud segment; an annular stationary structure surrounding the shroud segments; and a hanger received in the open channel of each shroud segment and mechanically coupled to the stationary structure, each of the hangers passing through the respective open channel and including an enlarged portion having greater cross-sectional area than the open channel, the enlarged portion engaging the outer wall of the respective shroud segment, so as to retain the shroud segment radially relative to the stationary structure.

Abstract: A turbine flowpath apparatus for a gas turbine engine includes: a flowpath component exposed at least partially to a primary combustion gas flowpath of the engine, the flowpath component comprising low-ductility material; a metallic annular stationary structure surrounding the flowpath component, including a bearing surface which bears against the flowpath component, so as to restrain the flowpath component from axial movement in a first direction; and a spring element disposed between the flowpath component and the stationary structure which resilient urges the flowpath component in the first direction against the bearing surface.

Abstract: A turbine shroud apparatus for a gas turbine engine includes: a plurality of arcuate shroud segments arranged as an annular shroud, each of the shroud segments comprising low-ductility material and having a cross-sectional shape defined by opposed forward and aft walls, and opposed inner and outer walls, the walls extending between opposed first and second end faces, wherein an open channel is formed through the outer wall of each shroud segment; an annular stationary structure surrounding the shroud segments; and a hanger received in the open channel of each shroud segment and mechanically coupled to the stationary structure, each of the hangers passing through the respective open channel and including an enlarged portion having greater cross-sectional area than the open channel, the enlarged portion engaging the outer wall of the respective shroud segment, so as to retain the shroud segment radially relative to the stationary structure.

Abstract: A seal assembly comprising a first movable stator member movable between a sealing position and a non-sealing position, a second fixed stator member, the first stator member being movable relative to the second stator member, the seal assembly further comprising at least one flexure member coupled to the second stator member, and at least one biasing member coupled between the at least one flexure and the movable stator for biasing the movable stator to a non-sealing position.

Abstract: A multi sensor clearance probe with at least longitudinally and transversely spaced apart first and second sensors operable to measure first and second distances respectively between the sensors and a longitudinally spaced apart rotating rotor. The sensors being operable to measure blade tip clearances between radially outer turbine blade tips and an annular stator shroud circumscribing the blade tips. The blade tips may be squealer tips and the sensors operable to measure the distances between the sensors and tops of squealer tip walls and outwardly facing walls within cavities of the squealer tips. The probe may be operably connected to a controller for sending signals to the controller indicating the first and second distances for controlling an air valve used for active clearance control. Two or more of the probe may be used to determine rotor centerline offset.

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 multi sensor clearance probe with at least longitudinally and transversely spaced apart first and second sensors operable to measure first and second distances respectively between the sensors and a longitudinally spaced apart rotating rotor. The sensors being operable to measure blade tip clearances between radially outer turbine blade tips and an annular stator shroud circumscribing the blade tips. The blade tips may be squealer tips and the sensors operable to measure the distances between the sensors and tops of squealer tip walls and outwardly facing walls within cavities of the squealer tips. The probe may be operably connected to a controller for sending signals to the controller indicating the first and second distances for controlling an air valve used for active clearance control. Two or more of the probe may be used to determine rotor centerline offset.

Abstract: A turbine engine stator assembly in juxtaposition across a radial gap with a rotary blading assembly includes a radially movable shroud and a gap control member made of at least one shape memory alloy (SMA). The SMA is selected and preconditioned to deform pre-selected amounts to change the radial length of the gap during engine operation responsive to temperature about the SMA. A fluid flow means delivers fluid to the SMA at pre-selected temperatures during engine operation.

Abstract: A method assembling a seal assembly within a gas turbine engine. The method includes coupling a stationary stator member to a gas turbine engine including a rotating member, and coupling a primary seal assembly and a secondary seal assembly to the stationary stator member wherein the primary seal assembly includes a moveable stator member including at least one keyed slot, and at least one biasing member including at least one key. Moreover, the at least one key is slidably coupled within the at least one keyed slot to facilitate aligning the primary seal assembly and the secondary seal assembly with respect to the gas turbine engine, and the seal assembly facilitates sealing between the stationary stator member and the rotating member.

Abstract: A method of operating a gas turbine engine is provided. The gas turbine engine includes at least one engine casing and at least one rotor assembly. The method includes directing airflow through a supply pipe and into a heat exchanger, lowering the temperature of the airflow in the heat exchanger, and directing the cooled airflow into the engine casing to cool the casing.

Abstract: An annular blade retention plate for axially retaining rotor blades within slots of a rotor disk. The plate includes an annular plate web extending radially outwardly from a radially inner plate hub to a plate rim and an annular radially outwardly open outer channel in a radially outwardly facing outer surface of the rim. A sealing ring is received within the outer channel and the sealing ring has axial rectangularly shaped cross-sections. An annular axially forwardly open inner channel in an annular ridge on a forward plate face of the plate web has an annular seal wire received therein. In a rotor assembly having a rotor disk supporting a plurality of circumferentially spaced apart rotor blades mounted in corresponding axially extending slots and the plate mounted to the rotor disk the sealing ring is in sealing engagement with radially inwardly facing surfaces of blade platforms of the blades.

Abstract: A system for controlling blade tip clearance in a turbine. The system includes a stator including a shroud having a plurality of shroud segments and a rotor including a blade rotatable within the shroud. An actuator assembly is positioned radially around the shroud and includes a plurality of actuators. A sensor senses a turbine parameter and generates a sensor signal representative of the turbine parameter. A modeling module generates a tip clearance prediction in response to turbine cycle parameters. A controller receives the sensor signal and the tip clearance prediction and generates at least one command signal. The actuators include at least one actuator receiving the command signal and adjusts a position of at least one of the shroud segments in response to the command signal.

Abstract: A method for controlling fluid leakage between a first pressure region and a second pressure region within a gas turbine engine using a first sealing member and a second sealing member. The first sealing member is movably coupled to a portion of the gas turbine engine, and a space defined generally between a portion of the first sealing member and a portion of the second sealing member fluidly couples the first pressure region to the second pressure region. The method includes moving the first sealing member towards the second sealing member using fluid pressure within a portion of the engine, and, using the first and second sealing members, substantially controlling fluid leakage between the first pressure area and the second pressure area through the space generally without contacting the first sealing member with the second sealing member.

Abstract: A method for controlling fluid leakage between a first pressure region and a second pressure region within a gas turbine engine using a first sealing member and a second sealing member. The first sealing member is movably coupled to a portion of the gas turbine engine, and a space defined generally between a portion of the first sealing member and a portion of the second sealing member fluidly couples the first pressure region to the second pressure region. The method includes moving the first sealing member towards the second sealing member using fluid pressure within a portion of the engine, and, using the first and second sealing members, substantially controlling fluid leakage between the first pressure area and the second pressure area through the space generally without contacting the first sealing member with the second sealing member.

Abstract: A rotary machine has a rotor and a surrounding stator. The rotor has an outer surface with an upstream larger-radius first section, a downstream smaller-radius second section, and an intervening third section which has an area facing in a direction other than perpendicular or parallel to the axis of the rotor. In one example, the area includes a first convex area and a second concave area. The machine also has a first brush seal with bristles whose free ends are positioned near the second section, and the machine may also include a second brush seal with bristles whose free ends are positioned near the first section and with a front plate having a ledge projecting away from its corresponding bristles.

Abstract: A brush seal segment useful, when circumferentially arrayed with other such segments, to seal the gap between a rotor and a surrounding casing of a rotary machine such as a gas or steam turbine. Brush-seal bristles are positioned between a brush-seal back plate and a brush-seal front plate with the free end of each bristle extending beyond the edges of the plates. The front plate has a portion extending to the edge of the front plate with the portion spaced apart from the bristles. In one example, the portion has an array of through holes. In another example, the portion has a ledge projecting generally away from the bristles.