Abstract: Aircraft engines include an engine housing, a core assembly arranged within the engine housing and comprising an engine shaft arranged axially within the engine housing extending in a forward-aftward direction, and a tail cone assembly attached to an aft end of the engine housing. The tail cone assembly includes a tail cone housing and an aircraft machine arranged within the tail cone housing the aircraft machine comprising a rotor shaft. An input shaft is configured between the engine shaft and the rotor shaft and a rotor coupling configured to sealing connect the rotor shaft and the input shaft, the rotor coupling configured to providing sealing engagement between the rotor shaft and the input shaft during at least one of relative axial displacement and relative radial displacement between the rotor shaft and the input shaft.

Abstract: A seal plate for a rotary machine includes a hub centered on a central axis of the rotary machine, a disk portion extending radially outwards from the hub, and a variable lattice structure in an interior of the seal plate. The variable lattice structure includes a first region of the seal plate having a first lattice structure, and a second region of the seal plate having a second lattice structure. The second lattice structure of the second region is denser than the first lattice structure of the first region. The second region is a deflection region, a stress region, or an energy containment region of the seal plate.

Abstract: A field grading composite body includes a polymeric matrix and a particulate filler distributed within the polymeric matrix. Particles of the particulate filler include a core formed from a semiconductor material, an oxide mixed layer deposited on the core, and conducting oxide layer. The conducting oxide layer deposited on the oxide mixed layer to provide an electrical percolation path through the polymeric matrix triggered by strength of an electric field extending through the field composite body. Conductors and methods of making field grading composite bodies for conductors are also described.

Abstract: The present disclosure provides for cooling systems, assemblies and methods (e.g., for semiconductor devices; for refrigerant cooling; for cryogenic cooling). More particularly, the present disclosure provides for mini-channel cold plate cooling assemblies, systems and methods for semiconductor devices (e.g., wide-bandgap (WBG) power semiconductor devices), with the cooling assemblies, systems and methods utilizing three-dimensional adaptive flow-paths using bi-metal fins. The present disclosure provides for mini-channel cold plate cooling assemblies, systems and methods that may improve cooling performance and/or enable local cooling control. The present disclosure provides for bi-metal strips that operate as both the surface-temperature sensors and actuators without input energy. The bi-metal strips guide the coolant flow to a low-drag channel when the surface temperature is low, and guide the coolant flow to the near-surface channel when the surface temperature is high.

Abstract: A turbo generator rotor assembly is provided and includes a generator, first and second bearings on a compressor-side and a turbine-side of the generator and a combination seal configuration in which leakage from the compressor cools the first bearing, the generator and the second bearing. The combination seal configuration leads to minimal leakage past the turbine with the generator and the first and second bearings being cooled with leakage flow from the compressor.

Abstract: A method of manufacturing an electric motor assembly includes inserting the pump motor stator into a vacuum chamber. The pump motor stator comprises a housing having a cavity formed therein and a pump motor stator located within the cavity. The pump motor stator contains an integral cooling tube located radially inward of the stator. The method also includes applying a vacuum to the pump motor stator in the vacuum chamber and flowing a potting material into a gap between the stator and the cooling tube and the stator, the gap extending a first distance longitudinally between the stator and the cooling tube. Pressure is applied to the potting material to push the potting material further into the gap.

Abstract: A power distribution system includes a variable frequency alternating current (AC) generator, an active rectifier electrically connected to the variable frequency AC generator such that AC power output from the variable frequency AC generator is rectified by the active rectifier, and a switching controller configured to detect a fundamental frequency of the AC power output and lock an active switch rate of the active rectifier to an integer multiple of the fundamental frequency.

Abstract: A drive shaft for an aircraft according to an example of the present disclosure includes, among other things, an elongated core extending between a pair of opposed couplings, an energy absorption layer made of a composite comprising metal, the energy absorption layer disposed on the core, and a first composite ballistic layer disposed along a length of the core.

Abstract: A multi-waste processing system includes a processing chamber. The processing chamber includes one or more heaters and a piston, and the processing chamber is configured to evaporate liquid waste and compact solid waste input. A condenser is operably connected to the processing chamber. The condenser is configured to condense water from the evaporated liquid waste output from the processing chamber. A gas and water separator is operably connected to the condenser. The gas and water separator is configured to separate water from the evaporated liquid waste output from the processing chamber. A recirculation pathway connects the gas and water separator to the processing chamber to recirculate gas from the gas and water separator to the processing chamber. The piston is actuated to keep the one or more heaters in close proximity to the solid waste and the liquid waste in the processing chamber.

Abstract: An example electrical power system includes a bus current controller configured to adjust a direct current (DC) provided on a DC bus, and a plurality of energy storage modules (ESMs). Each ESM includes at least one energy storage device, and includes a DC/DC converter configured to control charging of the at least one energy storage device from the DC bus and discharging of the at least one energy storage device onto the DC bus. A shared system controller is configured to control the bus current controller and the plurality of DC/DC converters. A method of controlling an electrical power system is also disclosed.

Abstract: A phase change material heat sink including: a carbon graphite matrix having one or more removed portions; and an expanded graphite located within the one or more removed portions.

Abstract: A failsafe electro-mechanical actuator, the actuator having: an output shaft having a first and second ends spaced apart from each other along a shaft axis, and outwardly facing helical grooves formed along the first end; a motor shaft surrounding the output shaft; a harmonic drive between the motor and output shafts that transfers motion between these shafts in a first mode of operation; ball bearings seated at the first end of the motor shaft and project inwardly from the motor shaft; in the first mode of operation: the ball bearings are disengaged from the output shaft and the output shaft rotates with the motor shaft, and in a second mode of operation, the motor shaft axially moves toward the first end of the output shaft; the motor shaft is rotationally fixed; and the ball bearings engage the helical grooves in the output shaft, whereby the output shaft rotates.

Abstract: In one aspect, a rotor shroud for a rotary machine includes a disk portion extending along and oriented about a central axis of the rotary machine, a transition portion extending from the disk portion, and a flared portion extending axially from the transition portion. The disk portion, the transition portion, and the flared portion include a plastic substrate and metal plating disposed on at least apportion of an outer surface of the plastic substrate. The plastic substrate has a matrix material and fibers embedded in the matrix material. The fibers have a first coefficient of thermal expansion. The metal plating has a second coefficient of thermal expansion. The fibers are selected such that a bulk coefficient of thermal expansion of the plastic substrate at the outer surface of the plastic substrate substantially matches the second coefficient of thermal expansion of the metal plating.

Abstract: In accordance with at least one aspect of this disclosure, a method includes installing a welding tool into a repair tool holder, ultrasonic welding a repair sheet to a part to be repaired with the welding tool, removing the welding tool from the repair tool holder, installing a machining tool into the repair tool holder, and ultrasonic machining a portion of the repair sheet that is welded to the part to be repaired to match an a predetermined geometry of the part to be repaired with the machining tool.

Abstract: A system for vane pitch actuation includes an electric motor with a rotary output shaft defining a drive axis. A worm shaft defines a drive axis, and is operatively connected to be driven in rotation about the drive axis by the rotary output shaft of the electric motor. A sync ring is defined about an engine axis that is orthogonal to the drive axis. The sync ring is configured to rotate about the engine axis over a range of positions for driving a plurality of variable pitch stator vanes to each have a pitch based on position of the sync ring. The sync ring includes a plurality of gear teeth for actuation of the sync ring by the electric motor.

Abstract: A power converter includes a field graded substrate, a plurality of power device dies attached to the field graded substrate, a polymer layer on the field graded substrate, one or more conductors over the polymer layer, and a plurality of power conditioning components mounted on the field graded substrate to form a power converter circuit. The field graded substrate includes a first conductor layer, a graded layer that blends conductor and insulator material, and a second conductor layer, the graded layer having an insulator core.

Abstract: A conical bearing includes a bearing sleeve, a bump foil, and a top foil. The bearing sleeve extends along an axis from a first open end to a second open end. The bearing sleeve has an axially tapered shape such that a first diameter of the bearing sleeve is greater than a second diameter of the bearing sleeve. An interior surface of the bearing sleeve has a non-circular profile. The bump foil is concentrically disposed within the bearing sleeve and includes bump foil pad segments extending circumferentially about the interior surface of the bearing sleeve. Each bump foil pad segment comprises a plurality of foil bumps and the plurality of foil bumps varies in stiffness along a circumference of the bump foil. The top foil is concentrically disposed within the bump foil and includes top foil pad segments extending circumferentially about an interior surface of the bump foil.

Abstract: An environmental control system includes an ambient air conduit and a bleed air conduit, an electric compressor connected to the ambient air conduit and a mechanical compressor connected to the electric compressor. The electric compressor is supported for rotation independent of the mechanical compressor. A turbine is operatively connected to the mechanical compressor, the turbine connected to both the ambient air conduit and the bleed air conduit to provide conditioned air to a conditioned air conduit. Computer program products and methods of providing conditioned air to conditioned air loads are also described.

Abstract: A torque limiter (TL) is provided for torque transmission (TT) to downstream components. The TL includes an input shaft, an output shaft and a torsional spring which is preloadable by a preload torque whereupon the torsional spring is fittable about the output shaft with the output shaft fit about the input shaft. For input shaft rotation, first TT paths proceed from the input shaft to the output shaft through the torsional spring when downstream torque of the downstream components deceeds the preload torque and a second TT path proceeds from the input shaft to an external structure when the downstream torque exceeds the preload torque.

Abstract: A shaft can include a first portion comprising a first material having first material properties, a disconnect portion comprising at least some of a second material having second material properties, and a third portion comprising a third material having third material properties. The disconnect portion can be positioned between the first portion and the third portion, the three material properties being configured such that the first portion is physically disconnected from the third portion in response to failure of the disconnect portion under at least one of a mechanical load and/or an electrical load and/or thermal load.