Abstract: A variable area, three-dimensional, converging/diverging nozzle assembly includes upstream converging nozzle flaps pivotally connected at their forward ends to an axially translatable radially inner unison ring, diverging downstream flaps pivotally connected to the downstream ends of the converging flaps, and external connectors pivotally connected at their downstream ends to the downstream ends of the diverging flaps and pivotally connected at their upstream ends to a radially outer unison ring. The unison rings are interconnected such that translation of either unison ring results in translation of both the converging flaps and the external connectors. The converging flaps rotate as they are moved axially, such as by the use of a cam track and cam follower, thereby changing in the C/D nozzle exit area ratio as the unison ring translates.

Abstract: A process for fabricating a resin bonded carbon fiber article, and in particular electrochemical cell electrode substrates and the like requiring different mean pore sizes in different areas, involves simultaneously heating and compacting different mixtures of carbon fibers and resin in different areas of an article forming mold, wherein the carbon fibers in each of the different mixtures have different, known bulk densities. The different bulk densities of the carbon fibers in the mixtures are chosen to yield the desired mean pore sizes and other properties in the article after heating and compacting the mixtures. Preferably, the different bulk densities are obtained using different carbon fiber lengths in the molding mixtures. The process is well suited to forming ribbed electrode substrates with preselected optimum mean pore sizes, porosities, and densities in the ribs, the webs connecting the ribs, and in the edge seals.

Abstract: An augmentor system for a gas turbine engine is drained of residual fuel after augmentor shutdown by means of a drain conduit connected to the augmentor fuel spray apparatus through a valve which opens upon augmentor shutdown. The outlet to the drain conduit is disposed within the flameholder. A pressure differential causes the residual fuel to flow from the spray apparatus into the drain conduit and thereupon into the flameholder, whereupon it is burned.

Abstract: The neck portion of a rotor blade includes an annular, axially projecting segment integral with the neck and having side edges abutting corresponding segments of adjacent blades to form a segmented annular ring which cooperates with static structure to define an interstage annular seal. Each blade also includes an air dam extending laterally from each side of the root neck and extending radially between the blade platform and the annular seal segment. The air dams of adjacent blades also abut each other to define an annular seal which prevents the axial flow of air across the rotor stage under the blade platforms between the blade root necks. In a preferred embodiment thin strips of silicone rubber are used to seal any gaps between the abutting edges of adjacent blades.

Abstract: An atomizer disk for use in the process of making metal powder by pouring molten metal onto the spinning disk is made from a plurality of contiguous, concentric, radially aligned elements having thermal conductivity properties which are selected to achieve appropriate temperature zones on the surface of the disk during operation. The central disk-like element is preferably a ceramic with low thermal conductivity. The outermost element is a high strength reinforcing ring which preferably also has high thermal conductivity. The annular elements between the outer ring and central disk should also have high thermal conductivity. By properly selecting the disk materials the heat extraction from the molten metal can be better controlled and larger disks may be constructed.

Abstract: Apparatus for forming coils of magnet wire and for inserting that magnet wire along the insulating wedges into the core of a stator comprises a transfer tool of circumferentially disposed wedge guides which receives wedges at a wedging station, is wound with coils of magnet wire by a push winding technique at a winding station, and then moves to an insertion station wherein the windings and wedges are pushed into a stator core. The wedge guides are designed to hold the wedges during the winding operation and also to receive the coils being formed as wire is pushed out of a nozzle rotating over the transfer tool. The coils fall by gravity between predetermined pairs of wedge guides. Finger elements are then inserted upwardly through the bore of the transfer tool. An empty stator core is placed on the finger elements, and the formed coils and wedges are pushed from the transfer tool into the stator core.

Abstract: In the process of forming metal powders by rotary atomization, the atomizer disk is first coated with a stable compound of the molten metal to be poured or, if the metal to be poured is an alloy, the disk is coated with a compound of the base metal of the alloy. The coating compound is selected on the basis of its melting point and that it can coexist with the molten metal to be poured, at the pour temperature, as indicated by phase diagrams of the materials involved. The molten metal is poured onto the coated, spinning disk, couples with the coating, and forms a stable skull of itself over the coating. Fine droplets of molten metal are thereafter flung from the disk, cooled and collected.

Abstract: A gas turbine engine control for an engine which experiences airflow distortion at the engine inlet face plane uses a static pressure measurement upstream of the face plane along with a corrected rotor speed to generate a signal indicative of the average total pressure at the engine face plane. This signal is combined with a total pressure signal from elsewhere in the engine to generate a pressure ratio signal which is compared to the scheduled pressure ratio for the current operating conditions. Control logic then adjusts either the fuel flow rate to the burners or the area of the exhaust nozzle in response to the difference between these pressure ratios.

Abstract: In an electrochemical cell wherein during operation electrolyte evaporates into a reactant gas stream, the evaporated electrolyte, before it leaves the cell as a vapor in the reactant gas exhaust stream, is condensed from the gas stream by reducing the temperature of the reactant gas stream just before it exits the cell. The condensed electrolyte is taken up by the cell electrode and redistributed throughout the cell by diffusion and capillary action.

Abstract: The trailing edge region of an airfoil includes a slot formed between the pressure and suction side walls with an array of pedestals extending across the slot, wherein selected pairs of pedestals are connected by a barrier wall adjacent either the pressure or suction side of the slot. The barrier walls extend inwardly toward the opposite side wall only partway across the slot to trip the thermal boundary layer of the cooling air flowing in the slot. These barrier walls alternate, in the downstream direction, between the pressure side and the suction side of the slot such that cooling air flowing downstream must move back and forth between the pressure and suction side walls in order to pass over these walls. Simultaneously, as the cooling air travels downstream, it snakes around the pedestals. The result is that the cooling air flows through the slot along a plurality of spiral or vortex-like flow paths resulting in improved heat transfer.

Abstract: A gas turbine engine exhaust nozzle assembly having vertical thrust capability comprises a two-dimensional converging/diverging nozzle and a veer flap for forward thrust operation and a rotatable hood type deflector for vertical thrust operation, wherein the forward edge of the veer flap is attached to the downstream edge of the deflector hood. During forward thrust operation, the hood and rear edge of the divergent flap portion of the converging/diverging nozzle are moved synchronously to maintain the rear edge of the divergent flap portion and the front edge of the veer flap adjacent each other such that the veer flap is aligned with and acts as an extension of the divergent flap portion of the converging/diverging nozzle. Preferably, means are provided to independently trim the orientation of the veer flap to maximize thrust. A movable ventral flap defines the nozzle throat between itself and the deflector hood when the hood is deployed for vertical thrust.

Abstract: A hinge assembly includes a hinge pin which passes through interfitting knuckles of two leaves which are to be hinged. An L-shaped tab lock has, in one embodiment, one leg trapped between a pair of the knuckles and another leg which passes through a slot in the head of the hinge pin and is folded over to prevent axial movement of the pin relative to the tab lock and knuckles. Preferably a flat on the side of the pin head abuts a flat surface on one of the leaves to prevent movement of the pin relative to that leaf.

Abstract: A lightweight exhaust nozzle/thrust reverser for a gas turbine engine comprises a flap-type exhaust nozzle with a thrust reverser door built into a cutout within each flap. The flaps may be hinged at their forward edges to the engine exhaust duct and may either be actuated or may float freely. Preferably, when the reverser doors are stowed they blend smoothly with the internal and external surfaces of the flaps. Actuation means deploys the doors such that they extend into the gas flow path and coact with each other to form a wall which blocks the axial flow of gas, and they simultaneously open the cutout within which they are disposed and redirect the exhaust gas through the cutouts in an upstream direction. In a preferred embodiment the flaps define the divergent portion of a convergent/divergent exhaust nozzle.

Abstract: Gasifying liquid hydrocarbon fuels, and in particular liquid heavy hydrocarbon fuels, at high fuel-to-air equivalence ratios with no significant soot formation comprises the steps of mixing the fuel and heated air in a prevaporization and mixing zone to prevaporize only a portion of the liquid fuel using only the sensible heat in the air, passing the partially vaporized fuel-air mixture through a catalyst zone to catalytically combust at least some of the prevaporized portion of the fuel while simultaneously, without the use of an external heat source, vaporizing and gasifying as-yet unvaporized fuel using the additional heat generated by the catalytic combustion, wherein the length of the catalyst zone, the catalyst configuration, and the fuel flow rate have been preselected to obtain the desired amount of gasification and to sustain continuous gasification with no significant soot formation.

Abstract: A ribbed substrate for an electrochemical cell electrode is made from a mixture of carbon fibers and carbonizable resin and has a mean pore size in the ribs which is 60-75% of the mean pore size of the web portions of the substrate which interconnect the ribs. Preferably the mean pore size of the web portion is 25-45 microns; and, if the substrate includes edge seals parallel to the ribs, the edge seals preferably have a mean pore size no greater than about ten microns. Most preferably the substrate has the same ratio of carbon fibers to polymeric carbon in all areas, including the ribs, webs, and edge seals. A substrate according to the present invention will have better overall performance than prior art substrates and minimizes the substrate thickness required for the substrate to perform all its functions well.

Abstract: A porous fuel cell component, such as an electrode substrate, has a densified edge which forms an improved gas seal during operation when soaked with electrolyte. The edges are made from the same composition as the rest of the component and are made by compressing an increased thickness of this material along the edges during the fabrication process.

Abstract: A thin electrochemical cell separator plate with greatly improved properties is made by molding and then graphitizing a mixture of preferably 50 percent high purity graphite powder and 50 percent carbonizable thermosetting phenolic resin, the graphite molding powder particles having a specified preferred shape and a size distribution requiring 31 to 62 weight percent of the particles to be less than 45 microns in size.

Abstract: A fuel cell module comprising a stack of fuel cells with reactant gas manifolds sealed against the external surfaces of the stack includes a constraint system for providing a compressive load on the stack wherein the constraint system maintains the stack at a constant height (after thermal expansion) and allows the compressive load to decrease with time as a result of the creep characteristics of the stack. Relative motion between the manifold sealing edges and the stack surface is virtually eliminated by this constraint system; however it can only be used with a stack having considerable resiliency and appropriate thermal expansion and creep characteristics.

Abstract: In an electrochemical cell wherein during operation electrolyte evaporates into a reactant gas stream, the evaporated electrolyte, before it leaves the cell as a vapor in the reactant gas exhaust stream, is condensed from the gas stream by reducing the temperature of the reactant gas stream just before it exits the cell. The condensed electrolyte is taken up by the cell electrode and redistributed throughout the cell by diffusion and capillary action.

Abstract: In a process for deaerating and purifying both the water which is recirculated in a coolant loop through a stack of fuel cells and the make-up water for the coolant loop, a portion of the water from the coolant loop is blown down into a deaerator water reservoir to which make-up water is added as required by the coolant loop. Water is withdrawn from the reservoir, purified, and then introduced into the coolant loop at a rate sufficient to maintain the desired amount of water circulating in the coolant loop. The blowdown provides some of the heat for deaerating the water; and the rate of blowdown flow into the reservoir is sufficient to maintain an acceptable level of impurities in the recirculating coolant loop water. Preferably, the blowdown flow rate is controlled as a function of the amount of make-up water required to be added to the coolant loop.