A shroud assembly for a gas turbine engine includes: at least one shroud hanger; an annular array of shroud segments carried by the child hanger at least one and arrayed about an engine centerline axis, each of the shroud segments having a flowpath side defining a portion of a primary engine flowpath, and an opposed backside facing the at least one shroud hanger, wherein the shroud segment is mounted to the at least one shroud hanger such that it is movable in a radial direction between an inboard position and an outboard position, in response to a balance of gas pressures prevailing on the flowpath side and the backside; and biasing means which urge each of the shroud segments towards one of the positions.

An apparatus for controlling turbine blade tip clearance is provided. The apparatus for controlling turbine blade tip clearance includes a turbine casing configured to guide a flow of combustion gas, an actuator ring rotatably mounted outside the turbine casing, a plurality of turbine blades rotatably mounted inside the turbine casing, a plurality of ring segments surrounding tips of the turbine blades and installed to form a predetermined gap with each tip, a plurality of rotary shafts each configured to have one end connected to several of the plurality of ring segments and the other end extending radially from the turbine casing, a link member configured to rotate an associated one of the rotary shafts according to circumferential rotational motion of the actuator ring, and a pusher member provided at an inner end of the rotary shaft to move the ring segments radially inward by rotation of the rotary shaft, wherein the actuator ring rotates back and forth in a predetermined angular range by an actuator installed outside the turbine casing.

An apparatus for controlling turbine blade tip clearance is provided. The apparatus for controlling turbine blade tip clearance includes a turbine casing configured to guide a flow of combustion gas, an actuator ring rotatably mounted outside the turbine casing, a plurality of turbine blades rotatably mounted inside the turbine casing, a plurality of ring segments surrounding tips of the turbine blades and installed to form a predetermined gap with each tip, a plurality of rotary shafts each configured to have one end connected to several of the plurality of ring segments and the other end extending radially from the turbine casing, a link member configured to rotate an associated one of the rotary shafts according to circumferential rotational motion of the actuator ring, and a pusher member provided at an inner end of the rotary shaft to move the ring segments radially inward by rotation of the rotary shaft, wherein the actuator ring rotates back and forth in a predetermined angular range by an actuator installed outside the turbine casing.

A tip gap control system for a ducted aircraft includes a flight control computer including an inner duct surface control module configured to generate an inner duct surface actuator command and a proprotor system in data communication with the flight control computer. The proprotor system includes a duct having active inner duct surfaces movable into various positions including a retracted position and an extended position. The proprotor system also includes proprotor blades surrounded by the duct and one or more actuators coupled to the active inner duct surfaces. The one or more actuators move the active inner duct surfaces between the various positions based on the inner duct surface actuator command, thereby controlling a tip gap between the proprotor blades and the duct.

A turbine guide apparatus, having multiple guide blades. Each guide blade has a first shroud and a second shroud formed on radial ends of a blade leaf having a first carrier for the guide blades. Each guide blade is fastened to the first carrier via a first shroud projection having a second carrier for the guide blades and is fastened on the second carrier via a second shroud projection. The first shroud projection is inserted into a groove of the first carrier in the radial direction and fastened in this groove via a bolt extending in the axial direction through the projection of the first shroud with radial mobility in this groove. The second shroud projection of the guide blade is fastened in the circumferential and radial direction via a pin extending in the axial direction into the projection of the second shroud and the second carrier.

A turbine guide apparatus, having multiple guide blades. Each guide blade has a first shroud and a second shroud formed on radial ends of a blade leaf having a first carrier for the guide blades. Each guide blade is fastened to the first carrier via a first shroud projection having a second carrier for the guide blades and is fastened on the second carrier via a second shroud projection. The first shroud projection is inserted into a groove of the first carrier in the radial direction and fastened in this groove via a bolt extending in the axial direction through the projection of the first shroud with radial mobility in this groove. The second shroud projection of the guide blade is fastened in the circumferential and radial direction via a pin extending in the axial direction into the projection of the second shroud and the second carrier.

Sealing arrangements and rotor assemblies are provided. A sealing arrangement includes a stationary component, a rotating component spaced apart from the stationary component. A clearance is defined between the stationary component and the rotating component. The sealing arrangement further includes a plurality of magnets embedded within the rotating component. The sealing arrangement further includes a brush seal having a frame and a plurality of magnetically responsive filaments. The plurality of magnetically responsive filaments each extending from the frame to a free end. The plurality of magnetically responsive filaments are attracted to the rotating component by the plurality of magnets. The plurality of magnetically responsive filaments at least partially covering the clearance, such that a flow of fluid across the clearance is restricted.

Flow restricting arrangements and rotor assemblies are provided. A flow restricting arrangement includes a stationary component and a rotating component. The rotating component is radially spaced apart from the stationary component such that a clearance is defined between the stationary component and the rotating component. A first magnet is embedded within the stationary component. A second magnet embedded within the rotating component. A plurality of magnetically responsive particles is contained within the clearance by a magnetic field produced by the first magnet and the second magnet. The plurality of magnetically responsive particles at least partially span the clearance.

Flow restricting arrangements and rotor assemblies are provided. A flow restricting arrangement includes a stationary component and a rotating component. The rotating component is radially spaced apart from the stationary component such that a clearance is defined between the stationary component and the rotating component. A first magnet is embedded within the stationary component. A second magnet embedded within the rotating component. A plurality of magnetically responsive particles is contained within the clearance by a magnetic field produced by the first magnet and the second magnet. The plurality of magnetically responsive particles at least partially span the clearance.

A turbine includes a first rotor and a second rotor that can rotate in opposite directions and are interleaved. The turbine further includes a ring to which abradable material is secured, the ring, unsegmented, extending between the first impellers of the first rotor and the second rotor, over a sector of between 350 and 360°, and, axially between an upstream end and a downstream end of the ring, the ring is held with the second rotor.