An assembly is provided for a turbine engine. This turbine engine assembly includes a first rotating structure, a turbine engine apparatus, a rotating coupler and a seal assembly. The first rotating structure is configured to rotate about a rotational axis. The turbine engine apparatus includes an electric machine and a second rotating structure. The electric machine includes an electric machine rotor and an electric machine stator. The second rotating structure is configured to rotate about the rotational axis and is coupled to the electric machine rotor. The rotating coupler is coupled to the first rotating structure by a first connection. The rotating coupler is coupled to the second rotating structure by a second connection. The seal assembly includes a rotating seal land and a stationary seal element. The rotating seal land is mounted onto the rotating coupler. The stationary seal element sealingly engages the rotating seal land.

A seal assembly includes an annular seal support, and an annular seal housing operably connected to the seal support. The seal housing includes a first axial surface facing away from the seal support, and a second axial surface opposite the first axial surface. A seal is located at the first axial surface. One or more first springs extend between the seal support and the second axial surface to urge the seal housing away from the seal support, and one or more second springs are located at the first axial surface to urge the seal housing toward the seal support.

A seal assembly includes a carbon seal that has a sealing surface. A seal seat has a sealing surface and is positioned for rotation relative to the carbon seal. A diamond-like carbon coating at least partially forms the sealing surface on the seal seat.

A gas turbine engine including: an exhaust diffuser including an inner tube and an outer tube that form therebetween an annular exhaust passage; a bearing chamber formed radially inside the inner tube for accommodating a bearing that supports a rotor of a turbine; a plurality of hollow struts extending across the exhaust passage; an oil introduction passage extending through one of the struts for introducing oil to be supplied to the bearing chamber; an oil drain passage extending through one of the struts for draining the oil from an exhaust oil inlet opened on a bottom surface of the bearing chamber; and an oil discharge passage for discharging a portion of the oil having passed through the oil introduction passage toward the oil drain inlet.

An apparatus has: a first member; a shaft rotatable relative to the first member about an axis; and a seal system. The seal system has: a seal carried by the first member and having a seal face; a seal housing; a seat carried by the shaft and having a seat face in sliding sealing engagement with the seal face; and a plurality of coil springs biasing the seal face against the seat face, each coil spring having a first end and a second end. The seal has a plurality of spring compartments. Each of the plurality of coil springs is partially within a respective associated compartment of the plurality of spring compartments.

A hybrid electric propulsion system including: a gas turbine engine comprising a low speed spool, a high speed spool, and a combustor; a lubrication circuit comprising a bearing compartment, a supply pump, and a scavenger pump; an electric motor configured to augment rotational power of the low speed spool or the high speed spool; and a controller operable to: control the electric motor based upon a pressure differential between an interior of the bearing compartment and an exterior of the bearing compartment and to drive rotation of the low speed spool and/or the high speed spool via the electric motor responsive to a thrust command while fuel flow to the combustor is inhibited.

Turbine engine assembly comprising: an external casing (28) of a low-pressure compressor (4), an annular wall (30) and an oil tank (46) with a circular chamber (48) around an axis (14) of the compressor. The wall (30) comprises an inner surface (38) delimiting an primary guide path for the flow of the compressor, and an external surface (40) radially opposite the inner surface and delimiting the internal chamber (48) of the tank (46).

A bearing support designed to be secured to a stationary turbojet element for supporting a journal, including a cone which widens from a central portion for supporting the journal to a portion for securing to the stationary element, a cylindrical body extending the portion for securing to the stationary element while surrounding the cone, an upstream skirt carried by the cone for defining an upstream enclosure for the central portion, and at least one downstream revolution element carried by the cone for defining a downstream enclosure for the central portion. The bearing support can be made as a single part produced by additive manufacturing.

A seal system for a bearing compartment of a gas turbine engine includes an annular rotating seal seat in contact with the seal element to form a dry seal interface therebetween to separate am oil-wetted zone from a dry zone. The annular rotating seal seat forms a dry zone annular space adjacent to the annular seal element and the rotating component. The annular rotating seal seat having an oil return passageway through the rotating seal seat to provide a communication path from the dry zone annular space outboard of the rotating component back to the oil-wetted zone.

A gas turbine engine includes a buffer system that communicates a buffer supply air to a portion of the gas turbine engine. The buffer system includes a first bleed air supply having a first pressure, a second bleed air supply having a second pressure that is greater than the first pressure, and a valve that selects between the first bleed air supply and the second bleed air supply to communicate the buffer supply air to the portion of the gas turbine engine.