Abstract: Aspects of the disclosure are directed to a rotatable shaft, and a plurality of bearings coupled to the rotatable shaft, where the plurality of bearings include a first bearing, a second bearing, and a third bearing, where the first bearing defines an axial first bearing centerline, where the second bearing defines an axial second bearing centerline, where the third bearing defines an axial third bearing centerline, and where the axial second bearing centerline is radially offset from the axial first bearing centerline and the axial third bearing centerline.

Abstract: A piezo-actuated valve, system, and method of exciting gas turbine turbomachinery are provided. The piezo-actuated valve includes a valve body extending along a first axis between a first and second end, the valve body defining a first opening near the first end, a second opening near the second end, a third opening centrally located on the valve body, and a valve cavity between the first opening and the second opening, a tube connected to the third opening and extending from the valve body along a second axis transverse to the first axis, a shuttle valve assembly slidably disposed within the valve body, wherein the shuttle valve slides between the first end to a first stopper and the second end to a second stopper, a first piezo injector having an injector tip extending through the first opening, and a second piezo injector having an injector tip extending through the second opening.

Abstract: Aspects of the disclosure are directed to a rotatable shaft, and a plurality of bearings coupled to the rotatable shaft, where the plurality of bearings include a first bearing, a second bearing, and a third bearing, where the first bearing defines an axial first bearing centerline, where the second bearing defines an axial second bearing centerline, where the third bearing defines an axial third bearing centerline, and where the axial second bearing centerline is radially offset from the axial first bearing centerline and the axial third bearing centerline.

Abstract: A fluid pulse device includes a piezo actuated valve, a piezo injector, a delivery system, and a control system. The piezo actuated valve has a valve body, a tube, and a piston assembly. The valve body defines a first opening, a second opening, and a valve cavity that is disposed between the first opening and the second opening. The tube extends from the valve body. The piston assembly includes a piston head and a stem that is connected to the piston head. The piezo injector has an injector tip that extends through the first opening. The delivery system is fluidly connected to the piezo injector. The control system is operatively connected to the piezo injector and is configured to actuate the piezo injector to provide a fluid pulse.

Abstract: A piezo-actuated valve, system, and method of exciting gas turbine turbomachinery are provided. The piezo-actuated valve includes a valve body extending along a first axis between a first and second end, the valve body defining a first opening near the first end, a second opening near the second end, a third opening centrally located on the valve body, and a valve cavity between the first opening and the second opening, a tube connected to the third opening and extending from the valve body along a second axis transverse to the first axis, a shuttle valve assembly slidably disposed within the valve body, wherein the shuttle valve slides between the first end to a first stopper and the second end to a second stopper, a first piezo injector having an injector tip extending through the first opening, and a second piezo injector having an injector tip extending through the second opening.

Abstract: A fluid pulse device includes a piezo actuated valve, a piezo injector, a delivery system, and a control system. The piezo actuated valve has a valve body, a tube, and a piston assembly. The valve body defines a first opening, a second opening, and a valve cavity that is disposed between the first opening and the second opening. The tube extends from the valve body. The piston assembly includes a piston head and a stem that is connected to the piston head. The piezo injector has an injector tip that extends through the first opening. The delivery system is fluidly connected to the piezo injector. The control system is operatively connected to the piezo injector and is configured to actuate the piezo injector to provide a fluid pulse.

Abstract: A fan shaft support assembly for a gas turbine engine includes first and second bearing assembles supported by a bearing support structure. The bearing support structure includes a first support including a first support end supporting the first bearing assembly and a second support including a second support end supporting the second bearing assembly. The first support end and the second support end are spaced apart to provide a preload on the first and second bearing assemblies.

Abstract: A fan shaft support assembly for a gas turbine engine includes first and second bearing assembles supported by a bearing support structure. The bearing support structure includes a first support including a first support end supporting the first bearing assembly and a second support including a second support end supporting the second bearing assembly. The first support end and the second support end are spaced apart to provide a preload on the first and second bearing assemblies.

Abstract: A fan containment case assembly 30 of a gas turbine engine 10 includes a hardened fan case liner 42 disposed therein. In the event of a fan blade loss condition, the hardened fan case liner allows for circumferential movement of the fan blade tips 38 around the fan case 48. Thus, the liner reduces the destructive cutting away of the fan case, minimizing damage to the fan case and decreasing torque loading of the fan case from rotor deflections. Alternate embodiments of the fan case liner are described.

Abstract: According to the present invention, a brush seal is provided having a side plate, a back plate, and a bristle pack disposed between the side plate and the back plate. The side plate is in contact with an upstream surface of the bristle pack. The back plate is in contact with a downstream surface of the bristle pack. The back plate includes a plurality of apertures positioned to provide a gas path through the back plate for gas exiting the bristle pack. In some embodiments, the back plate further includes an exit channel disposed in the back plate surface contiguous with the bristle pack, aligned with the apertures. In some embodiments, the radial length of the side plate in contact with the bristle pack is less than the radial length of the back plate in contact with the bristle pack.

Abstract: A mount for a gearbox accessory for a gas turbine engine substantially isolates the accessory from direct mechanical loading from the engine case during normal engine operating conditions and couples the accessory to the engine case during high rotor imbalance conditions to minimize interface loads between the gearbox and the accessory. By coupling the gearbox to the accessory, the two are displaced substantially in unison, thereby minimizing interface stresses therebetween. Various construction details of the mount for the gearbox accessories are disclosed.

Abstract: A bearing system has a bearing axis initially coincident with a shaft axis and an outer member axis. An inner bearing element is associated with and coupled to the shaft. An outer bearing element is associated with and coupled to the outer member. A first of the inner and outer bearing elements is coupled to its associated member via a coupling having a trunnion stiffness which, upon experiencing a trunnion moment above a threshold moment, releases from an initial stiffness to a reduced stiffness, less than the initial stiffness, entering a released condition and allowing the shaft axis to locally rotate out of parallel with the outer member axis.

Abstract: A gearbox mounting arrangement for a gas turbine engine includes a plurality of variable stiffness positioning links that attach the gearbox housing to the engine case. The links include a first portion that is connected to the engine case, a second portion connected to the gearbox and the first and second portion releasably connected by an isolation mechanism having a lower stiffness than the first and second portions. During a high rotor imbalance condition such as a fan blade loss condition, the links yield to a lower stiffness level than during normal operation as the isolation mechanism becomes operational in response to the application of high axial loads and the first and second portions partially disengage. The partial disengagement of the portions of the links of the present invention results in partially isolating the gearbox from the deflections experienced by the engine case. Thus, only a percentage of engine case imbalance loads are transmitted through the links to the gearbox.

Abstract: A locator for a gearbox mount for a gas turbine engine includes a mounting plate having a first stub shaft that extends from the plate into a receptacle in the gearbox, a second stub shaft that extends from the plate into a receptacle in the engine case and a load sensitive mechanism disposed in either one of the stub shafts. During a high rotor imbalance event such as a fan blade loss condition, the load sensitive mechanism shears to partially decouple the gearbox from the engine case to minimize damage caused by high rotor imbalance loads. Alternate embodiments of the load sensitive mechanisms in the stub shaft are disclosed, including a diaphragm and a wall that yield to shear loads.

Abstract: An apparatus for supporting a rotatable shaft within a gas turbine engine during a high rotor imbalance condition includes a first bearing and a fixed support frame. One of the support frame or shaft includes a one-piece flange that has a first portion, a second portion and a failure region with a predetermined load capacity, which connects the first and second portion together. The bearing is radially disposed between the rotatable shaft and the fixed support frame, and is supported by the second portion of the flange. The bearing provides a load path between the fixed support frame and the rotatable shaft until a high rotor imbalance condition when the failure region fails in response to the application of loads that exceed the load capacity of the failure region. The failure of the failure region then provides for the separation of the first portion of the flange from the second portion and the elimination of the load path through the bearing.

Abstract: A containment case (130) for a turbine engine circumscribes an array of rotatable blades and comprises a penetration resistant containment ring (152) and an impact isolator (138a, 138b) extending from the containment ring. The containment case has an impact zone (136) which is the region where any blade fragment which separates from a blade is anticipated to strike the containment case. The containment ring is axially coincident with the impact zone, and the impact isolator is axially spaced from the impact zone. In one embodiment, The impact isolator is a circumferentially extending convolution. During operation, the impact isolator protects the integrity of a connection (139, 141) between the containment case (130) and an adjacent case (62, 64) and reduces the severity of forces transmitted to components (108) mounted on the case.

Abstract: A support arrangement for a rotor shaft (10) includes a bearing (28) radially interposed between the shaft and a support frame (26). The bearing has a durable support (100) and a destructible support (104). The destructible support is nested within a circumferentially extending channel (78) having three-dimensionally curved surfaces (82, 84). An adjacent oil seal (44) has similar three-dimensionally curved surfaces (52, 54) In the event that the rotor becomes unbalanced during operation, the destructible support disengages from its housing (76) and glides radially within the channel to restrain the rotor longitudinally while precluding the transmission of imbalance forces from the rotor to the frame. The curved character of the seal surfaces preserves the integrity of the seal so that loss of oil will not prevent continued, low speed operation of the rotor. An optional, temporarily operable damper (148) attenuates especially severe vibrations immediately following the onset of the imbalance.