Abstract: A gas turbine engine is provided having: a turbomachine; a fan section having a fan rotatable by the turbomachine; a nacelle enclosing the fan; and an engine controller positioned within the nacelle. The nacelle defines an inner surface radius (r) along the radial direction inward of the engine controller, wherein the engine controller defines a radial height (?r) along the radial direction, a total volume (V), and a normalized radius (r?). The normalized radius (r?) is a ratio of the inner surface radius (r) to the total volume (V) to cube root, and wherein these parameters are related by the following equation: 0.1 r ? ? 1 < ? r r < K r ? ? 4 / 3 . wherein the normalized radius (r?) is between 1.25 and 8 and K is equal to 40%, or the normalized radius (r?) is between 2.75 and 4.5 and K is equal to 65%.

Abstract: An orifice assembly includes a first member defining an orifice having a first dimension in a compressed state and a thermally-sensitive material arranged adjacent to the first member. The thermally-sensitive material has a rigid, first state that applies force to the first member so as to maintain the first dimension of the orifice in the compressed state and a flexible, second state configured to release the force applied to the first member. As such, when subjected to temperatures above a predetermined temperature threshold, the thermally-sensitive material changes from the rigid, first state to the flexible, second state to allow the first dimension of the first member in the compressed state to passively expand to a decompressed, second dimension, the second dimension being larger than the first dimension.

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 gas turbine engine is provided having: a turbomachine; a fan section having a fan rotatable by the turbomachine; a nacelle enclosing the fan; and an engine controller positioned within the nacelle. The nacelle defines an inner surface radius (r) along the radial direction inward of the engine controller, wherein the engine controller defines a radial height (?r) along the radial direction, a total volume (V), and a normalized radius (r?). The normalized radius (r?) is a ratio of the inner surface radius (r) to the total volume (V) to cube root, and wherein these parameters are related by the following equation: 0 . 1 ? ( r ? ) - 1 < ? ? r r < K ? ( r ? ) - 4 / 3 , wherein the normalized radius (r?) is between 1.25 and 8 and K is equal to 40%, or the normalized radius (r?) is between 2.75 and 4.5 and K is equal to 65%.

Abstract: An engine control system may be configured to perform a method of controlling thermal bias in a turbomachine. An exemplary method may include determining a thermal bias-value for the turbomachine, and performing a cooling treatment based at least in part on the thermal bias-value. The thermal bias-value may include a difference between an upward temperature-value corresponding to a first one or more temperature measurements of an upward portion of the turbomachine and a downward temperature-value corresponding to a second one or more temperature measurements of a downward portion of the turbomachine. The cooling treatment may include at least one of: circulating air through at least a portion of the turbomachine, and rotating a shaft of the turbomachine with a motoring system.

Abstract: A sub-cooler for a sub-cooling cryogenic refueling system is disclosed herein. The sub-cooler includes a first valve to separate flowing cryogenic fuel into a primary flowline and an auxiliary flowline, a second valve to reduce the saturated pressure and temperature of the cryogenic fuel in the auxiliary flowline, a cryogenic heat exchanger to transfer heat from the primary flowline to the auxiliary flowline, a temperature sensor to measure the temperature of the sub-cooled cryogenic fuel in the primary flowline, and a sub-cooler controller to control the effective areas of the primary flowline inlet and the auxiliary flowline inlet at the first valve.

Abstract: An engine control system may be configured to perform a method of controlling thermal bias in a turbomachine. An exemplary method may include determining a thermal bias-value for the turbomachine, and performing a cooling treatment based at least in part on the thermal bias-value. The thermal bias-value may include a difference between an upward temperature-value corresponding to a first one or more temperature measurements of an upward portion of the turbomachine and a downward temperature-value corresponding to a second one or more temperature measurements of a downward portion of the turbomachine. The cooling treatment may include at least one of: circulating air through at least a portion of the turbomachine, and rotating a shaft of the turbomachine with a motoring system.

Abstract: A method of operating a fuel system for a vehicle having an engine, the fuel system comprising a fuel delivery system, the fuel delivery system including a liquid hydrogen delivery assembly and a regulator assembly, the regulator assembly having a buffer tank, the method including: providing a first flow of hydrogen fuel from a liquid hydrogen fuel tank through the liquid hydrogen delivery assembly to the regulator assembly, wherein providing the first flow of hydrogen fuel includes pumping the first flow of hydrogen fuel through the liquid hydrogen delivery assembly using a pump at a first fuel flowrate; receiving data indicative of a commanded fuel flowrate to the engine, wherein the commanded fuel flowrate is higher than the first fuel flowrate; and providing stored hydrogen fuel from a gaseous fuel storage to the engine.

Abstract: An aircraft including a fuselage, a power generator configured to provide power to the aircraft, and at least one fuel tank for holding fuel for the power generator, and a fuel delivery assembly. The fuel tank is positioned in the fuselage and is configured to hold hydrogen fuel in a liquid phase. The fuel tank has a chamber for holding the hydrogen fuel and a fuel extraction line fluidly coupled to the chamber. The fuel extraction line extends from the fuel tank in a forward direction of the fuselage and at a downward angle relative to a centerline of the fuselage. The fuel delivery assembly is fluidly coupled to the fuel extraction line and fluidly connects the fuel tank to the power generator. The fuel delivery assembly is configured to provide the hydrogen fuel from the fuel tank to the power generator.

Abstract: In one embodiment, a membrane electrode assembly of a fuel cell has an anode aspect and a cathode aspect. A fuel distribution structure is disposed adjacent to the anode aspect. The fuel distribution structure has a fuel feed port configured to receive and inject liquid fuel to a flow field plate. The flow field plate has flow channels formed therein that split and spread from the fuel feed port to exit ports. The flow channels are configured to convey heat to fuel passing there through to substantially convert the liquid fuel to vaporous fuel within the flow channels. The exit ports are configured to deliver the resulting vaporous fuel to the anode aspect to substantially uniformly distribute fuel across the anode aspect. Further, an enthalpy exchanger and heat spreader assembly is in thermal contact with the fuel distribution structure and configured to provide to it heat from fuel cell operation.

Abstract: A fuel cell system which includes a fuel distribution structure that uniformly distributes vaporizing fuel to a fuel cell is provided. As the fuel travels in a flow field channel in the fuel distribution structure, it is substantially converted to a vapor by the heat of the fuel cell operation in such a manner that the resulting vapor pressure works to substantially uniformly distribute fuel evenly outwardly across substantially the entire active area of the anode aspect of one or more membrane electrode assemblies in the system, and whereby localized, uneven “hot spots” of fuel at the anode aspects are substantially prevented. A pair of enthalpy exchanger and heat spreader assemblies include a cathode current collector element that also has a heat spreader plate that collects and redirects heat in the fuel cell system, the assembly acting to manage the heat, temperature and condensation in the fuel cell system.

Abstract: A spring loaded direct oxidation fuel cell assembly reduces the effects of precompression relaxation. A near flat spring and a distribution plate form a spring assembly that is disposed between a membrane electrode assembly and one of the current collectors in the fuel cell. The components are assembled into a fuel cell assembly and are precompressed, and a spring yielding process is performed. While precompression is being applied, a set of pins and a plastic frame are insert molded around the fuel cell assembly to hold the components in place. Subsequently, as the precompression relaxes, the spring assembly forces act to maintain an evenly distributed compression on the MEA, thereby compensating for the loss of precompression. A related method of manufacturing a fuel cell assembly is provided.

Abstract: A spring assembly for use with a direct oxidation fuel cell system is provided. The spring assembly includes a pair of spring elements, placed over each of the major dimensions of the fuel cell, such that the top and bottom spring elements provide at least a portion of the load to the fuel cell for the required compression. The springs are designed to be fully compressed under the design pressure and are held in the compressed state by two side clamps thus providing a uniform planar pressure distribution across the fuel cell system. The spring elements each include several grooves formed therein extending towards center of the element. The side clamps include fastening members which are fingerlike extensions that fit within the grooves of the spring elements to hold the springs in tight engagement over the fuel cell system, with out bolts, pins or other fasteners.

Abstract: A fuel cell system which includes a fuel distribution structure that uniformly distributes vaporizing fuel to a fuel cell is provided. As the fuel travels in a flow field channel in the fuel distribution structure, it is substantially converted to a vapor by the heat of the fuel cell operation in such a manner that the resulting vapor pressure works to substantially uniformly distribute fuel evenly outwardly across substantially the entire active area of the anode aspect of one or more membrane electrode assemblies in the system, and whereby localized, uneven “hot spots” of fuel at the anode aspects are substantially prevented. A pair of enthalpy exchanger and heat spreader assemblies include a cathode current collector element that also has a heat spreader plate that collects and redirects heat in the fuel cell system, the assembly acting to manage the heat, temperature and condensation in the fuel cell system.

Abstract: A heat spreader assembly that provides electrical, thermal and structural functions to the fuel cell. The heat spreader assembly comprises two bulk composite material layers, and a heat spreader element. The heat spreader element includes a copper layer sandwiched between two stainless steel layers. The stainless steel layers are bonded to the bulk composite layers by a conductive thermal set adhesive. The lamination applied to the stainless steel layers enables heat and electricity to flow from the cathode while maintaining low resistance among other layers of the fuel cell. The copper layer diffuses heat across the layer and functions as cathode current collector for a fuel cell. The bulk composite material layers function as a cold side of an enthalpy exchanger system and a cathode flow field. Further the composite material includes flow channels formed throughout the material to evenly distribute incoming air over the enthalpy exchanger membrane and to the cathode of the MEA.

Abstract: A spring loaded direct oxidation fuel cell assembly reduces the effects of precompression relaxation. A near flat spring and a distribution plate form a spring assembly that is disposed between a membrane electrode assembly and one of the current collectors in the fuel cell. The components are assembled into a fuel cell assembly and are precompressed, and a spring yielding process is performed. While precompression is being applied, a set of pins and a plastic frame are insert molded around the fuel cell assembly to hold the components in place. Subsequently, as the precompression relaxes, the spring assembly forces act to maintain an evenly distributed compression on the MEA, thereby compensating for the loss of precompression. A related method of manufacturing a fuel cell assembly is provided.

Abstract: The present invention discloses a process for manufacturing a fuel cell and an associated fuel cell array that includes novel pre-shaped current collectors and conforming compression plates. The current collectors are pre-shaped to counteract any deflection of the fuel cell after compression is released during manufacture. The pre-shaped current collectors may bend outwards by the same amount as previously, however, the overall compression relaxation may be much lower because the pre-shaped current collectors are bending back into the flat position, as opposed to away from it. Also provided with the present invention are associated mold plates that induce the desired pre-shaping to the current collectors.

Abstract: An open or split type MRI apparatus has two axially spaced magnet coil half sections separated and supported by a compact support structure. Only two diametrically opposed supports are needed to react the high axial and torsional loads produced or received by the MRI apparatus. One support is loaded under pure compression, and the other support is loaded under compression and tension.

Abstract: A cylindrical magnet assembly for use in magnetic resonance imaging apparatus has a radially compact construction which eliminates prior manufacturing steps. Recesses are formed in insulation layers for receiving complimentary shaped bus bars. Because the bus bars are dimensioned to fit flush within the recesses, they do not add to the radial growth of the magnet assembly.

Abstract: An open or split type MRI apparatus has two axially spaced magnet coil half sections separated and supported by a compact support structure. Only two diametrically opposed supports are needed to react the high axial and torsional loads produced or received by the MRI apparatus. One support is loaded under pure compression, and the other support is loaded under compression and tension.