Abstract: A flow transfer apparatus for transferring cooling flow from a primary gas flowpath to a turbine rotor. The apparatus includes a first supply plenum communicating with the primary gas flowpath and first inducers, the first inducers configured to accelerate a first fluid flow from the first supply plenum and discharge it toward the rotor with a tangential velocity; a second supply plenum communicating with the primary gas flowpath and second inducers, the second inducers configured to accelerate a second fluid flow from the second supply plenum towards the rotor with a tangential velocity; and a cooling modulation valve operable to selectively permit or block the second fluid flow from the primary gas flowpath to the second supply plenum. The valve includes a flow control structure disposed in the primary gas flowpath and an actuation structure extending to a location radially outside of a casing defining the primary gas flowpath.

Abstract: A flow transfer apparatus for transferring cooling flow from a primary gas flowpath to a turbine rotor. The apparatus includes a first supply plenum communicating with the primary gas flowpath and first inducers, the first inducers configured to accelerate a first fluid flow from the first supply plenum and discharge it toward the rotor with a tangential velocity; a second supply plenum communicating with the primary gas flowpath and second inducers, the second inducers configured to accelerate a second fluid flow from the second supply plenum towards the rotor with a tangential velocity; and a cooling modulation valve operable to selectively permit or block the second fluid flow from the primary gas flowpath to the second supply plenum. The valve includes a flow control structure disposed in the primary gas flowpath and an actuation structure extending to a location radially outside of a casing defining the primary gas flowpath.

Abstract: A flow transfer apparatus for transferring cooling flow from a primary gas flowpath to a turbine rotor. The apparatus includes a first supply plenum communicating with the primary gas flowpath and first inducers, the first inducers configured to accelerate a first fluid flow from the first supply plenum and discharge it toward the rotor with a tangential velocity; a second supply plenum communicating with the primary gas flowpath and second inducers, the second inducers configured to accelerate a second fluid flow from the second supply plenum towards the rotor with a tangential velocity; and a cooling modulation valve operable to selectively permit or block the second fluid flow from the primary gas flowpath to the second supply plenum. The valve includes a flow control structure disposed in the primary gas flowpath and an actuation structure extending to a location radially outside of a casing defining the primary gas flowpath.

Abstract: Active clearance control systems for gas turbine engines are disclosed. An example active clearance control system may include a generally circumferentially mounted spray tube comprising a plurality of impingement holes arranged to impinge thermal control air on a clearance control component of a case; a rigid mounting assembly substantially rigidly coupling the spray tube to the case; and/or a sliding mounting assembly coupling the spray tube to the case while permitting limited relative movement between the spray tube and the case in a direction generally parallel with an engine axis. The sliding mount may be coupled to the case generally axially forward of the rigid mount. A ratio of the stand-off distance to the impingement hole diameter may be less than about 8. A ratio of the arc spacing to the impingement hole diameter may be less than about 15.

Abstract: A flow transfer apparatus for transferring cooling flow from a primary gas flowpath to a turbine rotor. The apparatus includes a first supply plenum communicating with the primary gas flowpath and first inducers, the first inducers configured to accelerate a first fluid flow from the first supply plenum and discharge it toward the rotor with a tangential velocity; a second supply plenum communicating with the primary gas flowpath and second inducers , the second inducers configured to accelerate a second fluid flow from the second supply plenum towards the rotor with a tangential velocity; and a cooling modulation valve operable to selectively permit or block the second fluid flow from the primary gas flowpath to the second supply plenum. The valve includes a flow control structure disposed in the primary gas flowpath and an actuation structure extending to a location radially outside of a casing defining the primary gas flowpath.

Abstract: Active clearance control systems for gas turbine engines are disclosed. An example active clearance control system may include a generally circumferentially mounted spray tube comprising a plurality of impingement holes arranged to impinge thermal control air on a clearance control component of a case; a rigid mounting assembly substantially rigidly coupling the spray tube to the case; and/or a sliding mounting assembly coupling the spray tube to the case while permitting limited relative movement between the spray tube and the case in a direction generally parallel with an engine axis. The sliding mount may be coupled to the case generally axially forward of the rigid mount. A ratio of the stand-off distance to the impingement hole diameter may be less than about 8. A ratio of the arc spacing to the impingement hole diameter may be less than about 15.