A compressor assembly includes an impeller rotatable about a central axis and a seal assembly. The seal assembly includes a labyrinth seal defining a seal interface with a sealing element of the impeller and a seal support ring into which the labyrinth seal is installed. The seal support includes a deflector ramp fluidly downstream of the seal interface. The deflector ramp is configured to turn an airflow leaking through the seal interface radially inwardly toward the central axis. A plurality of tortuous pathways are formed in a downstream surface of the seal support ring and are configured to diffuse a tangential component of the airflow.

A compressor assembly includes an impeller rotatable about a central axis and a seal assembly. The seal assembly includes a labyrinth seal defining a seal interface with a sealing element of the impeller and a seal support ring into which the labyrinth seal is installed. The seal support includes a deflector ramp fluidly downstream of the seal interface. The deflector ramp is configured to turn an airflow leaking through the seal interface radially inwardly toward the central axis. A plurality of tortuous pathways are formed in a downstream surface of the seal support ring and are configured to diffuse a tangential component of the airflow.

One embodiment is a rotor system comprising a duct ring; a hub disposed centrally to the duct ring; first and second stators each connected between the duct ring and the hub; first and second control vanes rotatably connected to the first and second stators, respectively; a structural hoop having a first end connected to the first control vane and a second end connected to the second control vane, the structural hoop for translating rotation of the first control vane about a vane axis to the second control vane; and a mechanism for restricting at least one of forward-aft movement and side-to-side movement of the structural hoop relative to the duct ring.

An alpha-alumina coated turbocharger turbine wheel includes a hub portion, a plurality of blades disposed about the hub portion, each blade of the plurality of blades having a leading edge and a trailing edge, a centerline passing axially through the hub portion, and a back-side wall defined radially between the leading edge of each blade of the plurality of blades and the centerline. The turbocharger turbine wheel is made of a metal alloy and a surface coating layer of alpha-alumina. The surface coating layer of alpha-alumina may be disposed only on the hub portion, the plurality of blades, and a radially-outer portion of the back-side wall. The radially-outer portion is defined between a radial distance from the centerline and the leading edge of each blade of the plurality of blades. Alternatively, the surface coating layer of alpha-alumina may be disposed on the hub portion, the plurality of blades, and an entirety of the back-side wall.

A rotor assembly has a drive shaft and a bladed rotor mounted to the drive shaft for rotation therewith. A dampening material is bonded to the rotor at a location where there is torsional strain energy present. Shear forces in the damping material are used to convert the torsional strain energy into heat energy, thereby providing torsional vibration damping.

A turbomachine including a stator, a rotor mounted on a shaft, a first bearing and a second bearing downstream of the first bearing in a direction of air circulation at the inlet of the turbomachine, the first bearing forming an axial abutment linked to the stator, the second bearing including an inner ring secured to the shaft and an outer ring mounted on an arm secured to the stator, the second bearing including rolling elements in axial support on the inner ring and on the outer ring. The outer ring includes a radially extending ring portion. The turbomachine also includes an axial force application device mounted between the arm and the ring portion.

A rotor drum for an aircraft turbomachine includes an annular wall extending around a longitudinal axis (A), the annular wall carrying rotor blades and having at least one bleed device configured to allow at least one liquid to pass through the annular wall. The bleed device includes a series of three adjacent circular orifices, the three orifices being aligned along a line and having a central orifice of larger diameter D1 and two lateral orifices of smaller diameter D2 diametrically opposed with respect to the central orifice.

A turbomachine comprising a ducted fan, a low-pressure turbine shaft and a reduction gearbox housed in a casing between the fan and the low-pressure turbine shaft, the fan rotor supplying airflow to a primary stream and a secondary stream and comprising a hub of diameter D1, wherein—the diameter D3 of the fan rotor is greater than 82 inches (2.08 metres), —the pressure ratio of the fan is between 1.10 and 1.35, the turbomachine comprises a low-pressure compressor separate from the fan, the reduction gearbox being interposed between the fan rotor and a turbine shaft of the low-pressure compressor, and wherein the reduction gearbox casing has an outside diameter D2 greater than the diameter D1 of the hub, the pitch diameter D4 of the reduction gearbox ring being between 0.15 and 0.35 times the fan rotor diameter.

A wheel assembly for a gas turbine engine includes a disk, a plurality of blades, and a platform system that includes a plurality of platforms and pins. The disk is configured to rotate about an axis during operation of the gas turbine engine. The blades each include a circumferentially extending root received in the disk and an airfoil that extends radially away from the root. The platforms are arranged around the wheel to define a flow path of the gas turbine engine and the pins extend into the platforms and the disk to couple the platforms with the disk.

A vacuum pump generally comprises a low pressure portion and a high pressure portion separated by a gas impermeable partition. Gas molecules exit the low pressure portion through an opening in the partition and passively impinge on a featureless rotatable surface in the high pressure portion. A drive rotates the rotatable surface with tangential velocity in the supersonic range at multiple times the most probable velocity of the impinging gas molecules. Impinging gas molecules are ejected outwardly from the periphery of the rotatable surface generating a substantial net outward flow of gas and reducing the pressure in the low pressure portion. The vacuum pump is effective to reduce the pressure in the low pressure portion to a target minimum pressure without using seals to prevent gas molecules from leaking back to the low pressure portion and without using blades or vanes to actively impact the gas molecules.