A machine includes a liquid lubrication system and a shaft, the shaft being rotatable about a rotation axis, the shaft including a first part, a second part engaged coaxially with the first part, and a journal bearing between the first part and the second part, the first part being rotatable relative to the second part about the rotation axis, a helical feature disposed between the first part and the second part and configured to define a helical pump between the first part and the second part, the pump being hydraulically connected to the liquid lubrication system, the journal bearing being disposed adjacent to the helical feature.

A device for lubricating and cooling a turbomachine rolling bearing is at least partially annular. The device comprises a first duct and a second duct inclined with respect to the first duct. The first duct is configured to be in thermal contact with an outer ring of the rolling bearing that at least partially surrounds same. The second duct is fluidically connected to the first duct. The first duct is configured to circulate the lubricant for cooling the outer ring, towards a discharge outlet of the lubricant. The second duct is configured to eject the lubricant through a lubrication outlet towards the rolling bearing.

A gas turbine engine rotor assembly comprises a torque tube, turbine stage and stiffening mass. The torque tube comprises a shaft extending from a forward location to an aft end, and a shaft fastening flange disposed at the aft end. The turbine stage comprises a disc, a disc adapter extending forward from the disc, and a disc fastening flange extending from the disc adapter and couplable to the shaft fastening flange at an interface. The stiffening mass is positioned proximate the interface to reduce operational stress in the torque tube. A method of reducing operational stress in a rotor assembly comprises de-stacking a rotor stack, separating a first stage rotor disc adapter from a torque tube, attaching a stiffening mass to an inner diameter of one or both of the disc adapter and the torque tube, attaching the disc adapter to the torque tube, and re-stacking the rotor stack.

The present disclosure relates to methods for starting and rapidly decelerating a turbomachine in a power generation system that utilizes a supercritical fluid in a closed cycle.

A rotating machine including a thrust bearing configured to receive an axial thrust exerted by a rotor. The thrust bearing may be configured to transfer the axial thrust from the rotor to a housing or other structural component of the rotating machine using a plurality of ball bearings. The rotating machine includes a magnetic apparatus configured to cause the rotating machine to exert an axial force on the thrust bearing in the direction of the axial thrust of the rotor, such that the magnetic apparatus loads the ball bearings in the direction of the axial thrust. The magnetic apparatus may be configured to generate a magnetic field causing a first magnetic component of the magnetic apparatus to repel or attract a second magnetic component of the apparatus. The first magnetic component may be configured to rotate relative to the second magnetic component.

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).sup.1/2 and three hundred (ft/sec).sup.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.

The present disclosure is directed to a turbine engine (10) defining an axial direction and a radial direction. The turbine engine includes a fan or propeller assembly (14) comprising a gearbox; an engine core (20) comprising one or more rotors, wherein at least one of the rotors defines an axially extended annular hub; and a flexible coupling shaft (100) defining a first end and a second end along the axial direction, wherein the first end is connected to the engine core and the second end is connected to the gearbox, and further wherein the flexible coupling shaft extends from the one or more rotors to the gearbox in the axial direction and inward of the hub in the radial direction.

A casing for a bearing of a gas turbine engine includes a shaft extending along an axial direction. The casing includes an attachment feature at a radially outermost portion of the casing. The attachment feature is configured to be coupled to a static frame of the gas turbine engine. The casing further includes a plurality of support arms extend from the attachment feature to a radially innermost portion of the casing. At least one support arm of the plurality of support arms defines an internal cavity. Further, the radially innermost portion of the casing is configured to be coupled to an outer race of the bearing. The casing additionally includes a reinforcing member housed at least partially within the internal cavity of at least one support arm. Moreover, the reinforcing member includes a shape memory alloy material.

An actuation system includes a power drive unit that drives a plurality of drive shafts that each has a first end individually connected to the power drive unit. The power drive unit includes a geartrain including a plurality of individual gears that are offset relative to each other along the gearbox, and a motor-driven rotation of one of the plurality of individual gears drives rotation of the other individual gears, and each of the plurality of individual gears rotates to drive rotation of a respective one of the plurality of drive shafts. A plurality of torque brakes is mounted to the gearbox, the torque brakes being mechanically coupled to respective individual gears and drive shafts. When the torque being passed through is above a predetermined threshold value, a locking of one of the torque brakes stops rotation of all gears simultaneously to maintain positional symmetry in the actuation system.

A diffuser for an oil drainback system drain tube includes a flow chamber configured for attachment to an open end of a drain tube, wherein the flow chamber has a side wall and an end wall, and openings in at least the side wall.