Abstract: A rotational duct blocker for a gas turbine engine includes a duct blocker rotor and a duct blocker stator. The duct blocker rotor includes a plurality of first vane segments that extend radially between an inner rotor platform and an outer rotor platform, and a plurality of first flow apertures that extend axially through the duct blocker rotor. Each first flow aperture also extends circumferentially between respective adjacent first vane segments. The duct blocker stator includes a plurality of second vane segments that extend radially between an inner stator platform and an outer stator platform, and a plurality of second flow apertures that extend axially through the duct blocker stator. Each second flow aperture also extends circumferentially between respective adjacent second vane segments. The first vane segments move circumferentially relative to the second vane segments to regulate fluid flowing between the first flow apertures and the second flow apertures.

Abstract: A rotational duct blocker for a gas turbine engine includes a duct blocker rotor and a duct blocker stator. The duct blocker rotor includes a plurality of first flow apertures extending axially therethrough, and a plurality of roller elements connected to an inner rotor platform. The first flow apertures are arranged circumferentially around the inner rotor platform. The duct blocker stator includes a plurality of second flow apertures extending axially therethrough, and a roller element track located radially within the inner rotor platform and in rolling contact with the roller elements. The second flow apertures are arranged circumferentially around an inner stator platform that is located axially adjacent to the inner rotor platform. The duct blocker rotor rotates relative to the duct blocker stator to regulate fluid flowing between the first flow apertures and the second flow apertures.

Abstract: A rotational duct blocker for a gas turbine engine includes a duct blocker rotor and a duct blocker stator. The duct blocker rotor includes a plurality of first vane segments that extend radially between an inner rotor platform and an outer rotor platform, and a plurality of first flow apertures that extend axially through the duct blocker rotor. Each first flow aperture also extends circumferentially between respective adjacent first vane segments. The duct blocker stator includes a plurality of second vane segments that extend radially between an inner stator platform and an outer stator platform, and a plurality of second flow apertures that extend axially through the duct blocker stator. Each second flow aperture also extends circumferentially between respective adjacent second vane segments. The first vane segments move circumferentially relative to the second vane segments to regulate fluid flowing between the first flow apertures and the second flow apertures.

Abstract: A rotational duct blocker for a gas turbine engine includes a duct blocker rotor and a duct blocker stator. The duct blocker rotor includes a plurality of first flow apertures extending axially therethrough, and a plurality of roller elements connected to an inner rotor platform. The first flow apertures are arranged circumferentially around the inner rotor platform. The duct blocker stator includes a plurality of second flow apertures that extending axially therethrough, and a roller element track located radially within the inner rotor platform and in rolling contact with the roller elements. The second flow apertures are arranged circumferentially around an inner stator platform that is located axially adjacent to the inner rotor platform. The duct blocker rotor rotates relative to the duct blocker stator to regulate fluid flowing between the first flow apertures and the second flow apertures.

Abstract: A high performance rolling element bearing (5) which is particularly suitable for use in a cryogenically cooled environment, comprises a composite cage (45) formed from glass fibers disposed in a solid lubricant matrix of a fluorocarbon polymer. The cage includes inserts (50) formed from a mixture of a soft metal and a solid lubricant such as a fluorocarbon polymer.