Abstract: A bearing support assembly to support one or more bearings on a shaft. The bearing support assembly includes a bearing support frame configured to be coupled to a static frame, a plurality of ribs connected to the bearing support frame, and a bearing support connected to the plurality of ribs and configured to support a bearing of the one or more bearings. The bearing support assembly has a non-axisymmetric stiffness around a circumference of the bearing support assembly.

Abstract: An interdigitated turbine assembly for a gas turbine engine, the interdigitated turbine assembly including a first turbine rotor assembly interdigitated with a second turbine rotor assembly. A first static frame is positioned forward of the first turbine rotor assembly and the second turbine rotor assembly. The first turbine rotor assembly is operably coupled to an inner rotatable component of a gear assembly. The second turbine rotor assembly is operably coupled to an outer rotatable component of the gear assembly. The static structure is connected to the first static frame. A driveshaft is operably coupled to the outer rotatable component. A first bearing assembly is operably coupled to the driveshaft and the first static frame. A second bearing assembly is operably coupled to the first static frame and first turbine rotor assembly. A third bearing assembly is operably coupled to the first turbine rotor assembly and the second turbine rotor assembly.

Abstract: A turbomachine engine includes a core engine having one or more compressor sections, one or more turbine sections that includes a power turbine, and a combustion chamber in flow communication with the compressor sections and turbine sections. The turbomachine engine also includes a shaft coupled to the power turbine and characterized by a midshaft rating (MSR) between two hundred (ft/sec)1/2 and three hundred (ft/sec)1/2. In one aspect, the shaft has a redline speed between fifty and two hundred fifty feet per second (ft/sec). In another aspect, the shaft has a length L, an outer diameter D, and a ratio of L/D between twelve and thirty-seven.

Abstract: A turbomachine engine includes a core engine having one or more compressor sections, one or more turbine sections that includes a power turbine, and a combustion chamber in flow communication with the compressor sections and turbine sections. The turbomachine engine also includes a shaft coupled to the power turbine and characterized by a midshaft rating (MSR) between two hundred (ft/sec)1/2 and three hundred (ft/sec)1/2. In one aspect, the shaft has a redline speed between fifty and two hundred fifty feet per second (ft/sec). In another aspect, the shaft has a length L, an outer diameter D, and a ratio of L/D between twelve and thirty-seven.

Abstract: A damper seal for a turbomachine includes an annular body having an inner circumferential surface and an outer circumferential surface separated by a thickness. As such, the inner circumferential surface may define a plurality of cavities arranged into a plurality of circumferential rows and at least one partition positioned between at least two of the plurality of cavities. In addition, the inner circumferential surface may further define at least one plenum arranged between two of the plurality of circumferential rows.

Abstract: A rotor damping device for a turbomachine is provided. The rotor damping device includes a first fluid damper; and a second damper in communication with the first fluid damper, the second damper comprising a wire mesh, wherein the first fluid damper is transitionable between a working condition and an interruption condition, and wherein, during the interruption condition, the wire mesh of the second damper dampens vibration of the turbomachine.

Abstract: An epicyclic gearbox is configured to transfer rotational motion between a first rotating component and a second rotating component of the gas turbine engine. The gearbox includes a centrally located sun gear, two or more planet gears circumscribing the sun gear, and a ring gear circumscribing the plurality of planet gears. The gearbox is configured such that the sun gear is drivingly coupled to the first rotating component, such that rotation of the sun gear causes rotation of each planet gear, and such that the ring gear rotates relative to the plurality of planet gears. The gearbox includes one or more shape memory alloy dampers provided in association with the sun gear, the ring gear, and/or the plurality of planet gears. The shape memory alloy damper(s) is configured in order to reduce vibrations transferred through the epicyclic gearbox to the frame, the first rotating component, and/or the second rotating component.

Abstract: An interdigitated turbine assembly for a gas turbine engine, the interdigitated turbine assembly including a first turbine rotor assembly interdigitated with a second turbine rotor assembly. A first static frame is positioned forward of the first turbine rotor assembly and the second turbine rotor assembly. The first turbine rotor assembly is operably coupled to an inner rotatable component of a gear assembly. The second turbine rotor assembly is operably coupled to an outer rotatable component of the gear assembly. The static structure is connected to the first static frame. A driveshaft is operably coupled to the outer rotatable component. A first bearing assembly is operably coupled to the driveshaft and the first static frame. A second bearing assembly is operably coupled to the first static frame and first turbine rotor assembly. A third bearing assembly is operably coupled to the first turbine rotor assembly and the second turbine rotor assembly.

Abstract: A turbomachine engine and gear assembly is provided. The engine includes a first power input component rotatable along a first direction relative to the engine centerline axis, a second power input component rotatable along a second direction relative to the engine centerline axis, a power output component rotatable relative to the engine centerline axis, a static component fixed relative to a circumferential direction relative to a gear assembly centerline axis, and a gear assembly. The gear assembly includes a first rotatable gear operably coupled to the first power input component at a first interface. The first rotatable gear is operably coupled to the static component at a static component interface. The static component interface is configured to react against the first rotatable gear to rotate the first rotatable gear relative to the gear assembly centerline axis. The power output component is operably coupled to the first rotatable gear.

Abstract: Damping devices, turbomachines, and methods of damping vibration are provided. For example, a damping device for damping vibration of a shaft rotatable about an axis of rotation is provided. The damping device defines radial and axial directions. The damping device comprises a bearing, a housing, and a damper element. The housing and damper element define a cavity therebetween for receipt of a damping fluid. The cavity has a length along the axial direction that is curved away from the axis of rotation. As another example, a turbomachine comprising a shaft rotatable about an axis of rotation includes a damping device positioned annularly about the shaft. The damping device comprises a housing and a damper element defining a cavity therebetween for receipt of a damping fluid that has a curved shape. The cavity is curved in a plane extending along the radial and axial directions and including the axis of rotation.

Abstract: A propulsion system for an aircraft including a core engine connected to a forward frame and a turbine frame assembly, and an aft frame assembly is connected by a turbine casing to the core engine aft of the turbine frame assembly. A core cowl surrounds the core engine, wherein the core cowl is connected to the forward frame. A plurality of cowl mount links selectively loads the core cowl to the aft frame assembly and the turbine frame assembly, wherein the plurality of cowl mount links is each loaded by deflection of the core engine.

Abstract: A rotor support system for a gas turbine engine includes a rotatable drum rotor and a non-rotatable support casing. The rotor support system includes a bearing assembly configured for positioning between the rotatable drum rotor and the non-rotatable support casing. The bearing assembly includes, at least, a stationary support frame and a rotatable race. Further, the rotatable race is configured to engage the rotatable drum rotor at separate and discrete locations that are circumferentially spaced apart around the rotatable drum rotor.

Abstract: A gas turbine engine includes a rotatable drum rotor having a plurality of blades secured thereto. The blades extend radially inward of the rotatable drum rotor. The gas turbine engine also includes a support frame mounted radially outward of the rotating drum rotor and a rotor support system having a bearing assembly positioned between the rotatable drum rotor and the support frame. The bearing assembly includes, at least, a stationary component and at least one rotatable component. Further, the gas turbine engine includes a damper assembly for securing between the support frame and the rotatable drum rotor. Moreover, the damper assembly includes at least one damper secured between the support frame and the stationary component of the bearing assembly or to a surface of the rotatable drum rotor. As such, the damper(s) is configured to provide damping to the rotatable drum rotor during operation of the gas turbine engine.

Abstract: A composite fan casing for a gas turbine engine defining a central axis is generally provided. The composite fan casing includes a core having a plurality of core layers of reinforcing fibers bonded together with a thermosetting polymeric resin, wherein one or more of the plurality of core layers of reinforcing fibers comprises a shear thickening fluid. The core layer may include at least one fabric sheet comprising the reinforcing fibers.

Abstract: A gas turbine engine including a lubricant system defining a lubricant circuit through which a lubricant flows in fluid communication with a bearing assembly of the engine. The lubricant system selectively bypasses thermal communication of the lubricant and a heat sink based at least on a temperature of the lubricant within the lubricant circuit.

Abstract: A method for operating a turbine engine is provided. The method includes receiving operating data comprising at least an engine operation parameter, an environmental parameter, a location parameter, and a time parameter; operating the turbine engine based on a baseline ground operation schedule; generating an adjusted ground operation schedule based on the operating data and the baseline ground operation schedule, wherein generating the adjusted ground operation schedule is based on a machine learning algorithm; and operating the engine based on the adjusted ground operation schedule.

Abstract: A method of starting a gas turbine engine is generally provided. The engine includes a rotor assembly including a compressor rotor and a turbine rotor each coupled to a shaft. The rotor assembly is coupled to a bearing assembly within a casing enabling rotation of the rotor assembly. The method includes determining, based on a lubricant parameter, a period of time within which a rotational speed of the rotor assembly is maintained within a bowed rotor mitigation speed range; rotating the rotor assembly for the period of time within the bowed rotor mitigation speed range; and accelerating the rotor assembly to the combustion speed to ignite a fuel-oxidizer mixture for combustion.

Abstract: A damper seal for a turbomachine includes an annular body having an inner circumferential surface and an outer circumferential surface separated by a thickness. As such, the inner circumferential surface may define a plurality of cavities arranged into a plurality of circumferential rows and at least one partition positioned between at least two of the plurality of cavities. In addition, the inner circumferential surface may further define at least one plenum arranged between two of the plurality of circumferential rows.

Abstract: A gas turbine engine includes a rotatable drum rotor having a plurality of blades secured thereto. The blades extend radially inward of the rotatable drum rotor. The gas turbine engine also includes a support frame mounted radially outward of the rotating drum rotor and a rotor support system having a bearing assembly positioned between the rotatable drum rotor and the support frame. The bearing assembly includes, at least, a stationary component and at least one rotatable component. Further, the gas turbine engine includes a damper assembly for securing between the support frame and the rotatable drum rotor. Moreover, the damper assembly includes at least one damper secured between the support frame and the stationary component of the bearing assembly or to a surface of the rotatable drum rotor. As such, the damper(s) is configured to provide damping to the rotatable drum rotor during operation of the gas turbine engine.

Abstract: A rotor support system for a gas turbine engine includes a rotatable drum rotor and a non-rotatable support casing. The rotor support system includes a bearing assembly configured for positioning between the rotatable drum rotor and the non-rotatable support casing. The bearing assembly includes, at least, a stationary support frame and a rotatable race. Further, the rotatable race is configured to engage the rotatable drum rotor at separate and discrete locations that are circumferentially spaced apart around the rotatable drum rotor.