Abstract: A rotor assembly for a gas turbine engine includes a shaft co-rotatable with a rotor with an annular seal assembly that is carried within an annular channel within the shaft that provides a seal between the shaft and the bore. The annular seal assembly includes a first member that is configured to seal against a radial surface of the bore and a second member that is configured to seal against an axial surface of the annular channel.

Abstract: A rotor assembly for a gas turbine engine includes a shaft co-rotatable with a rotor with an annular seal assembly that is carried within an annular channel within the shaft that provides a seal between the shaft and the bore. The annular seal assembly includes a first member that is configured to seal against a radial surface of the bore and a second member that is configured to seal against an axial surface of the annular channel.

Abstract: A gas turbine engine includes a rotor that has a seal surface and a shaft that is rotatable about an engine central axis. The shaft has an annular seal channel that opens to the seal surface. There is a seal for sealing against the seal surface. The seal has channels formed therein that define a tortuous seal wall with interconnected spring ligaments such that the seal is elastically diametrically expandable for installation clearance around the shaft and, once on the shaft, elastically diametrically collapsible into the annular seal channel.

Abstract: A system for determining rotor-dynamic orbit information including an engine case supporting at least one engine stage, each at least one engine stage including a rotor having blades; at least one blade tip sensor operatively coupled to the engine case and in operative communication with the blades; at least one compensation sensor in operative communication with the at least one blade tip sensor; and an orbit controller in operative communication with the at least one blade tip sensor and the at least one compensation sensor.

Abstract: A fluid damping structure includes first and second annular elements, first and second inner seals, a first outer seal, a damping chamber, a supply plenum, a fill port, and a plurality of fluid passages. The first and second inner seals are disposed radially between and are engaged with the first annular element and the second annular element. The first outer seal forms a sealing interface between the first and second annular elements. The first outer seal is disposed radially outward from the first and second inner seals. The damping chamber is defined by the first and second annular elements and the first and second inner seals. The supply plenum is disposed contiguous with an axial side of the damping chamber and extends from the second inner seal to the first outer seal. The fill port is in fluid communication with the supply plenum and a source of damping fluid.

Abstract: An actively controlled squeeze film damper system comprises a housing defining an annulus receiving a damping fluid during operation, a lubricant source supplying damping fluid to the annulus, and a sensor assembly for measuring a parameter indicative of a compressibility of the damping fluid. A control device adjusts the compressibility of the damping fluid within a predefined range.

Abstract: An actively controlled squeeze film damper system comprises a housing defining an annulus receiving a damping fluid during operation, a lubricant source supplying damping fluid to the annulus, and a sensor assembly for measuring a parameter indicative of a compressibility of the damping fluid. A control device adjusts the compressibility of the damping fluid within a predefined range.

Abstract: A bearing assembly includes a bearing housing having a first bearing housing surface and a second bearing housing surface. The bearing housing surfaces are substantially axially parallel. A the first bearing housing surface has a first and second piston ring groove with a corresponding piston ring in each groove. A damper includes a first outer surface radially adjacent to and opposing the first bearing housing surface and a second outer surface radially adjacent to and opposing the second bearing housing surface. The second outer surface includes a third and fourth piston ring groove with a corresponding piston ring disposed in each groove. The bearing housing includes a damping fluid passage configured to provide damping fluid to a gap radially between the first outer surface and the first bearing housing surface and to a gap radially between the second outer surface and the second bearing housing surface.

Abstract: A bearing assembly includes a case, a bearing spring positioned inside the case, a first seal positioned between the case and the bearing spring, and a second seal. The a second seal is positioned between the case and the bearing spring and is spaced apart from the first seal, wherein the second seal is an adjustable seal that is movable between a closed position and an opened position to inhibit or allow, respectively, a fluid to flow from a cavity that is defined by the case, the bearing spring, the first seal and the second seal.

Abstract: A bearing assembly includes a case, a bearing spring positioned inside the case, a first seal positioned between the case and the bearing spring, and a second seal. The a second seal is positioned between the case and the bearing spring and is spaced apart from the first seal, wherein the second seal is an adjustable seal that is movable between a closed position and an opened position to inhibit or allow, respectively, a fluid to flow from a cavity that is defined by the case, the bearing spring, the first seal and the second seal.