A gas turbine engine includes a plurality of blades circumferentially spaced from each other. A plurality of rings are spaced radially outward from the plurality of blade. At least one actuator is in mechanical communication with the plurality of rings for moving the plurality of rings in an axial direction to create an axial gap adjacent at least one of the plurality of rings.

A system for controlling gas turbine engine rotor blades tip clearance is described. A rotor is mounted to an engine shaft, supported by a thrust bearing, for rotation within a gas path shroud circumscribing blades of the rotor, the gas path shroud having a non-cylindrical shape in the vicinity of the rotor blades. A rotary actuator is associated with the thrust bearing and configured for axial translation of the thrust bearing, to thereby axially translate the engine shaft and the rotor blades relative to the gas path shroud. This translation is configured to vary the blade tip clearance of the rotor.

A system for controlling gas turbine engine rotor blades tip clearance is described. A rotor is mounted to an engine shaft, supported by a thrust bearing, for rotation within a gas path shroud circumscribing blades of the rotor, the gas path shroud having a non-cylindrical shape in the vicinity of the rotor blades. A rotary actuator is associated with the thrust bearing and configured for axial translation of the thrust bearing, to thereby axially translate the engine shaft and the rotor blades relative to the gas path shroud. This translation is configured to vary the blade tip clearance of the rotor.

A semi-autonomous rapid response active clearance control system for a gas turbine engine includes an outer case, a carrier for a blade outer airseal positioned radially inward of the outer case, a blade outer airseal positioned radially inward of and mounted to the carrier, at least one electromechanical actuator attached to the outer case and selectively operable to move the carrier, and a sensing system. The sensing system includes a maneuver sensor housed within the actuator and configured to output a first signal, a position sensor mounted proximate to the blade outer airseal and configured to output a second signal, and a control means in communication with the maneuver sensor and the position sensor.

A semi-autonomous rapid response active clearance control system for a gas turbine engine includes an outer case, a carrier for a blade outer airseal positioned radially inward of the outer case, a blade outer airseal positioned radially inward of and mounted to the carrier, at least one electromechanical actuator attached to the outer case and selectively operable to move the carrier, and a sensing system. The sensing system includes a maneuver sensor housed within the actuator and configured to output a first signal, a position sensor mounted proximate to the blade outer airseal and configured to output a second signal, and a control means in communication with the maneuver sensor and the position sensor.

A gas turbine engine includes a compressor section and a turbine section. The turbine section includes at least one rotor and at least one blade extending radially outwardly from the rotor to a radially outer tip. A blade outer air seal assembly is positioned radially outwardly of the radially outer tip of the blade. The blade outer air seal has forward and aft hooks, and the forward and aft hooks are supported on forward and aft seal hooks of an attachment block. The blade outer air seal forward and aft hooks extend at angles relative to an upper surface of a web that is between 20 and 70 degrees. A method is also disclosed.

In a steam turbine including a rotor including a free side end fixed by a journal bearing in a radial direction and a fixed side end fixed by a thrust bearing in an axial direction, and a casing including a fixed side end fixed by the thrust bearing in the axial direction, a casing position adjustment device is configured to adjust an axial position of the casing with respect to the rotor due to thermal expansion. The casing position adjustment device includes: a low-pressure casing end plate, which is an end plate oriented to a free side in the axial direction in a low-pressure casing of the casing, and has a diaphragm deformable in the axial direction; and actuators, which are configured to deform the low-pressure casing end plate so that the low-pressure casing end plate extends toward the free side in the axial direction.

A system for controlling the clearance distance between an impeller blade tip of a centrifugal compressor and a radially inner surface of an impeller shroud in a turbine engine. The system comprises a thermal driver coupled between the impeller shroud and engine casing by hinged linkages. The thermal driver includes an annular ring and annular seal which together define thermal driver cavity. Relatively warm or relatively cool air supplied to the thermal driver cavity cause expansion and contraction, respectively, of the annular ring which is translated by linkages into axially forward and aft motion, respectively.

A turbofan engine includes: a cylindrical fan case; a fan rotatably disposed in the fan case and including a central member and multiple fan blades arranged on an outer circumference of the central member such that the fan blades are spaced apart from one another in a circumferential direction; an annular member disposed to surround the fan; and an elastic support device that supports the annular member to the fan case radially elastically such that a predetermined clearance is radially defined between the annular member and tips of the fan blades.

A compressor with negative coefficient of thermal expansion case material comprising a rotor having blades with tips, the case including an inner case comprising a negative coefficient of thermal expansion material, and a tip clearance located between the tips and the inner case; wherein the tip clearance is maintained responsive to a flow of air over the negative coefficient of thermal expansion material.