Abstract: A bipole power transmission scheme with two independent converts, two power feed and one return conduit. During operation of the bipole power transmission scheme under abnormal conditions, when a return conduit is faulty and unable to provide a return current path, each converter controller is programmed to monitor the first power feed in the first transmission conduit and the second power feed in the second transmission conduit and, if the first power feed in the first transmission conduit and the second power feed in the second transmission conduit differ from one another, at least one converter controller modifies the power infeed from its corresponding power source to reduce the difference between the first power feed and the second power feed.

Abstract: Methods, apparatus, systems and articles of manufacture are disclosed. An example apparatus includes a compressor comprising a rotor defining a radial direction and a circumferential direction, the rotor including a slot; a first blade and a second blade disposed in the slot, the first blade including a first platform and a first dovetail, the second blade including a second platform and a second dovetail; and a hollow block disposed circumferentially between the first blade and the second blade in the slot, the hollow block including: a platform interface portion to interface with the first platform and the second platform, the platform interface portion including a central opening defined by a circumferential face of the platform interface portion; and a hollow dovetail interface portion to couple the first dovetail and the second dovetail.

Abstract: A combustion section defines an axial direction, a radial direction, and a circumferential direction. The combustion section includes a casing that defines a diffusion chamber. A combustion liner is disposed within the diffusion chamber and defines a combustion chamber. The combustion liner is spaced apart from the casing such that a passageway is defined between the combustion liner and the casing. A fuel cell assembly is disposed in the passageway. The fuel cell assembly includes a fuel cell stack having a plurality of fuel cells each extending between an inlet end and an outlet end. Each fuel cell of the plurality of fuel cells includes an air channel and a fuel channel each fluidly coupled to the combustion chamber.

Abstract: A fuel cell unit that includes a support structure having a plurality of flow channels and an active layer membrane coupled with the support structure, the active layer membrane comprising at least one electrode layer. Each flow channel of the plurality of flow channels is configured to direct one of air and fuel across at least one electrode layer of an active layer membrane to create electric current. Each flow channel of the plurality of flow channels includes at least one enhancement feature that is configured to disrupt a formation of a boundary layer near a surface of the active layer membrane where reactions occur. The plurality of flow channels can be positioned in a zig-zag configuration to allow for an increase in power density of the fuel cell unit.

Abstract: A method for magnetizing a section of one or more permanent magnets arranged substantially in a V-shape, comprising: applying a first magnetic field such that magnetic flux lines are substantially perpendicular to a first leg of the V-shape, and removing the first magnetic field. Then the method comprises applying a second magnetic field such that magnetic flux lines are substantially perpendicular to a second leg of the V-shape, and removing the second magnetic field. Systems and methods for magnetizing sections of permanent magnet modules are also provided.

Abstract: A rotor blade assembly for a turbine engine, including an airfoil blade including an inner diameter end and an outer diameter end, a lower blade carrier coupled to the inner diameter end of the airfoil blade and rigidly coupled to a disk via a pin, an upper blade carrier coupled to the outer diameter end of the airfoil blade, and an outer drum coupled to the upper blade carrier via a radial joint. The radial joint supports radial motion of the upper blade carrier relative to an axis extending through a center of the rotor blade assembly.

Abstract: An aircraft includes a gas turbine engine, an electric motor, and a propulsion device. The gas turbine engine and the electric motor are configured to provide a target cumulative output to the propulsion device. An electronic control unit is configured to set the gas turbine engine to a first engine mode to provide a first engine output to the propulsion device, set the electric motor to a first motor mode to provide a first motor output to the propulsion device, a sum of the first engine output and the first motor output being within a predetermined range of the target cumulative output, and in response to a speed of the aircraft reaching a target speed and the first engine output increasing to a second engine output, set the electric motor to a second motor mode.

Abstract: A rake arm assembly mountable to a build table having an upper surface and an opposite lower surface is provided. The rake arm assembly includes a rake arm body extending in a direction transverse to a working axis and positionable at the upper surface of the build table, a first guide rail mountable to the lower surface of the build table and extending along the working axis, a first rake support member fixed to a first end of the rake arm body and movably supported on the first guide rail, a second rake support member fixed to an opposite second end of the rake arm body, and a guide pad fixed to a lower surface of the second rake support member and positionable at the lower surface of the build table.

Abstract: A method of fabricating a component is provided. The method includes depositing particles onto a build platform. The method also includes distributing the particles to form a build layer. The method further includes operating a consolidation device to consolidate a first plurality of particles along a scan path to form a component. The component includes a top surface spaced apart from the build platform and an outer surface. The outer surface extends between the build platform and the top surface, and at least a portion of the outer surface faces a substantially particle-free region of the build platform.

Abstract: Cover plate connections for a hollow fan blade are disclosed. An example fan blade includes a hollow body including a surface defining an airfoil, the hollow body including an aperture extending through the surface, a cover plate, and at least one connection element to couple the cover plate to the surface such that the cover plate encloses the aperture.

Abstract: A trunnion-to-disk connection for use on an open fan configuration of a gas turbine engine may include an integral trunnion and blade spar inserted through a trunnion aperture of a fan disk and supported by top bearing and a bottom bearing. A cavity can be provided between a trunnion of the integral trunnion and blade spar and the fan disk, as well as between the top bearing and bottom bearing. Pressurized hydraulic fluid can be supplied to the cavity to urge the integral trunnion and blade spar in a direction to preload the bearings. Prior to pressurization, and prior to installation of the bottom bearing, the trunnion can be inserted into a trunnion aperture of the fan disk such that an end of the trunnion extends past the fan disk to provide sufficient space to insert the bottom bearing from within the open interior of the fan disk.

Abstract: Part-span shrouds for pitch controlled aircrafts are disclosed herein. An example apparatus includes a first portion extending from a first airfoil, the first portion including a first surface, the first surface being convex, a second portion extending from a second airfoil towards the first airfoil, the second portion including a second surface the first airfoil circumferentially adjacent to the second airfoil, the second surface being concave, and an interface formed by the first surface and the second surface, the interface reacting circumferential loads between the first airfoil and the second airfoil.

Abstract: A combustor assembly for a gas turbine engine defining a radial direction and a circumferential direction includes a liner assembly at least partially defining a combustion chamber and including at least one liner formed of a ceramic matrix composite material and extending between a downstream end and an upstream end, the downstream end of the at least one liner defining an interface surface extending along the circumferential direction; and a seal member also formed of a ceramic matrix composite material and bonded to the interface surface of the at least one liner, the seal member defining a downstream surface for contacting an adjacent component to form a seal with the adjacent component.

Abstract: A converter includes a DC bus, a first DC-DC converter, a second DC-DC converter, and a plurality of circulating current suppression circuits. The first DC-DC converter is coupled to the DC bus and includes a first plurality of switches. The second DC-DC converter is coupled to the DC bus in parallel with the first DC-DC converter. The second DC-DC converter includes a second plurality of switches. The plurality of circulating current suppression circuits are coupled to the DC bus and are further respectively coupled to the first DC-DC converter and the second DC-DC converter. Each of the plurality of circulating current suppression circuits has a resonant frequency at or around a switching frequency for the first and second pluralities of switches. The plurality of circulating current suppression circuits is configured to suppress current at or around the switching frequency and pass at least direct current.

Abstract: An acoustic liner is provided. The acoustic liner includes a face sheet, a back sheet spaced from the face sheet, and a core layer defining a cellular structure disposed between the face sheet and the back sheet. The core layer includes a plurality of first resonant cells coupled to the back sheet. Each of the first resonant cells includes a first cell wall coupled to the back sheet along a first cell wall base edge, the first cell wall extending from the back sheet toward the face sheet, the first cell wall further coupled to the face sheet along a first cell wall top edge, wherein the first cell wall of each of the first resonant cells comprises a surface extension that extends from a surface of the first cell wall.

Abstract: A minimum creep life location (MCLL) on a blade for a turbine blade design is received. A temperature at the MCLL on the blade is monitored. When the temperature at the MCLL exceeds a predetermined threshold, a cooling air supply is adjusted to lower the temperature below the threshold during engine operation.

Abstract: A method for operating a generator of a wind turbine includes generating, via a controller, a time series of a plurality of operating signals of the generator. The method also includes applying at least one algorithm to the time series of the plurality of operating signals of the generator to generate a processed time series of the of the plurality of operating signals of the generator. Moreover, the method includes identifying, via the controller, patterns in the processed time series of the plurality of operating signals of the generator to identify one or more of at least one slip event occurring in the slip coupling or a surface health of the slip coupling. Further, the method includes implementing, via the controller, a control action when the at least one slip event occurring in the slip coupling is identified or the surface health of the slip coupling is indicative of degradation in the slip coupling.

Abstract: A gas turbine engine includes a compressor section with a compressor rotor shaft assembly including a plurality of compressor rotors longitudinally spaced apart from each other via respective ones of a plurality of shaft sections of a rotor shaft, each compressor rotor of the plurality of compressor rotors having a plurality of rotor vanes extending radially outward therefrom and being circumferentially spaced about the compressor rotor. A stator shroud assembly has a stator shroud casing surrounding the compressor rotor shaft assembly, a compressor flow passage being defined between the compressor rotor shaft assembly and the stator shroud casing. A pressurized air source generates a flow of pressurized air to be provided to the compressor section, and a plurality of pressurized airflow nozzles are connected with the pressurized air source and provide the flow of pressurized air into the compressor flow passage to cause the compressor rotor shaft assembly to rotate.

Abstract: A system and method of using a tool assembly is provided. The system includes a body, a first camera and a second camera fixed to the body, and a controller. The controller is configured to receive data indicative of images of a reference feature from the first camera, determine data indicative of a first spatial position of the first camera based at least in part on the received data indicative of the images of the reference feature, and determine data indicative of a second spatial position of the second camera based on the first spatial position, a known spatial relationship between the first location and the second location, or both. Further, the controller may be configured to receive data indicative of images of a target feature using the second camera, derive dimensions of the target feature based on the images, and generate a three-dimensional representation of the target feature.

Abstract: An apparatus a multiple layer structure having a sub-portion defining an impact zone, and having an inner composite fiber layer, an outer composite fiber layer overlying the inner composite fiber layer, and a woven glass layer, where the inner composite fiber layer, outer composite fiber layer, and the woven glass layer overly the impact zone.