Abstract: A fuel injection system is provided for gas turbines or the like which includes a pair of high pressure pumps which provide fuel and a carrier fluid such as air at pressures above the critical pressure of the fuel. A supercritical mixing chamber mixes the fuel and carrier fluid and the mixture is sprayed into a combustion chamber for burning therein. The use of fuel and a carrier fluid at supercritical pressures promotes rapid mixing of the fuel in the combustion chamber so as to reduce the formation of pollutants and promote cleaner burning.

Abstract: A steel alloy is produced by a process which includes using cold rolling at room temperature and subsequent heat treatment at temperatures ranging from 500.degree. to 650.degree. C.The resulting alloy exhibits excellent strength and toughness characteristics at cryogenic temperatures. This alloy consists essentially of about 10 to 16 percent by weight nickel, to about 1.0 percent by weight aluminum, and 0 to about 3 percent by weight of at least one of the following additional elements: copper, lanthanum, niobium, tantalum, titanium, vanadium, yttrium, zirconium and the rare earth metals, with the balance being essentially iron. The improved alloy possesses a fracture toughness ranging from 200 to 230 ksi.sqroot.in. and yield strengths up to 230 ksi.

Abstract: A retractable environmental seal for use in sealing the opening of the exit cone for a rocket nozzle comprising a diaphragm-like cover having a central region adapted to be seated in sealing relation with the periphery of the opening and characterized by radially extended failure zones for facilitating a pressure-induced rupture of the cover, and a plurality of angularly spaced tension springs connected with the peripheral portion of the cover for retracting fractured segments of the cover from the opening subsequent to a pressure-induced rupture thereof.

Abstract: Phenol or a phenol related compound is detected in an electrochemical cell comprising a cathodic compartment containing a cathode in an electrolyte solution containing ferrocyanide ion and an anodic compartment containing an anode formed by coating a gel containing a phenol or phenol related compound oxidizing enzyme onto the conductive substrate of said anode immersed into an electrolyte solution containing ferrocyanide ion into which pure oxygen is passed; means for maintaining a conductive relationship between anodic and cathodic compartments; and means connected to said anode and cathode for measuring the potential of the oxidation of said phenol or related compound.

Abstract: A seal assembly is provided for reducing the escape of fluids from between a housing and a shaft rotatably mounted in the housing. The seal assembly comprises a pair of seal rings resiliently connected to each other and disposed in side-by-side relationship. In each seal ring, both the internal bore surface and the radial face which faces away from the other seal ring are provided with a plurality of equi-spaced recesses known as Rayleigh step pads. The seal faces referred to are located adjacent a seating surface of the housing. Under normal operating conditions, the seal assembly is stationary with respect to the housing, and the recesses generate lift, keep the assembly spaced from the rotating shaft and allow slip therebetween. Due to expansion of the shaft resulting from rubbing contact with the seal assembly, the seal assembly can seize on the shaft, and slip will then occur between the radial faces and the housing.

Abstract: A solar array-ion thruster system including a power control circuit which provides for use of the thruster itself in operating the solar array at the maximum power point. The power control circuit is connected between the solar array and the ion thruster and receives voltage and current signals from the former. The control circuit multiplies the voltage and current signals together to produce a power signal which is differentiated with respect to time. The differentiator output is detected by a zero crossing detector and, after suitable shaping, the detector output is phase compared with a clock in a phase demodulator. An integrator receives no output from the phase demodulator when the operating point is at the maximum power point but is driven toward the maximum power point for non-optimum operation. A ramp generator provides minor variations in the beam current reference signal produced by the integrator in order to obtain the first derivative of power.

Abstract: A closed loop apparatus for spraying coolant against the back of a radiation target. The coolant is circulated through a closed loop with a bubble of inert gas being maintained around the spray. Mesh material is disposed between the bubble and the surface of the liquid coolant which is below the bubble at a predetermined level. In a second embodiment no inert gas is used, the bubble consisting of vapor produced when the coolant is sprayed against the target.

Abstract: A method of making composite material which provides low friction surfaces for materials in rolling or sliding contact. The composite material is self-lubricating and oxidation resistant up to and in excess of about 930.degree. C. The composite material is comprised of a metal component which lends strength and elasticity to the structure, a fluoride salt component which provides oxidation protection to the metal but may also enhance the lubrication qualities of the composite.

Abstract: A heterojunction or Schottky barrier photovoltaic device comprising a conductive base metal layer compatible with and coating predominately the exposed surface of the p-type substrate of the device such that a back surface field region is formed at the interface between the device and the base metal layer, a transparent, conductive mixed metal oxide layer in integral contact with the n-type layer of the heterojunction or Schottky barrier device having a metal alloy grid network of the same metal elements of the oxide constituents of the mixed metal oxide layer embedded in the mixed metal oxide layer, an insulating layer which prevents electrical contact between the conductive metal base layer and the transparent, conductive metal oxide layer, and a metal contact means covering the insulating layer and in intimate contact with the metal grid network embedded in the transparent, conductive oxide layer for conducting electrons generated by the photovoltaic process from the device.

Abstract: A gas path seal suitable for use with a turbine engine or compressor is provided. A shroud wearable or abradable by the abrasion of the rotor blades of the turbine or compressor shrouds the rotor blades. A compliant backing surrounds the shroud. The backing may be made of corrugated sheets or the like with adjacent layers having off-set corrugations, with axes of the folds parallel to the rotor axis. The sheets may be bonded together at points of contact by brazing, welding or the like. In another embodiment a compliant material is covered with a thin ductile layer. A mounting fixture surrounds the backing.

Abstract: To capture fine particulate matter in a gas such as air, a dielectric fluid is directed to the center of whichever face of a rotating disc is exposed to the air flow. The disc is comprised of two or more segments which bear opposite electrostatic potentials. As the dielectric fluid is centrifuged towards the periphery of the rotating disc, the fluid becomes charged to the same potential as the segment over which it is passing. Particulate matter is attracted to the charged segment and is captured by the fluid. The fluid then carries the captured particulate matter to a collection device such as a toroidal container disposed around the periphery of the disc. A grounded electrically-conductive ring may be disposed at the outer periphery of the disc to neutralize the captured particles and the fluid before they enter the container.

Abstract: The application discloses a back-well cell, for example, a solar cell which comprises a first semiconductor material of one conductivity type with one face having the same conductivity type but more heavily doped to form a field region arranged to receive the radiant energy to be converted to electrical energy, and a layer of a second semiconductor material, preferably highly doped, of opposite conductivity type on the first semiconductor material adjacent the first semiconductor material at an interface remote from the heavily doped field region. Instead of the opposite conductivity layer, one may employ a metallic layer to form a Schottky diode. If the metallic Schottky diode layer is used, no additional back contact is needed. A contact such as a gridded contact, pervious to the radiant energy may be applied to the heavily doped field region of the more heavily doped, same conductivity material for its contact.

Abstract: An apparatus for producing a structure in outer space from rolls of prepunched ribbon or sheet material that are transported from the earth to the apparatus located in outer space. The apparatus spins the space structure similar to a spider spinning a web utilizing the prepunched ribbon material. The prepunched ribbon material is fed through the apparatus and is shaped into a predetermined channel-shaped configuration. Trusses are punched out of the ribbon and are bent downwardly and attached to a track which normally is a previously laid sheet of material. The size of the overall space structure may be increased by merely attaching an additional roll of sheet material to the apparatus.

Abstract: A transparent, conductive collector layer containing conductive metal channels is formed as a layer on a photovoltaic substrate by coating a photovoltaic substract with a conductive mixed metal layer; attaching a heat sink having portions protruding from one of its surfaces which define a continuous pattern in combination with recessed regions among said protruding portions to said substrate such that said protruding portions of said heat sink are in contact with the conductive layer of said substrate; andHeating said substrate while simultaneously oxidizing the portions of the conductive layer exposed to a gaseous oxidizing substance forced into said recessed regions of said heat sink, thereby creating a transparent metal oxide layer on said substrate containing a continuous pattern of highly conductive metal channels in said layer.

Abstract: A gas turbine is provided wherein the thermal stresses in the turbine rotor are reduced. The rotor includes a central disc with a peripheral rim, and a plurality of blades extending radially outwardly from the rim, and to reduce thermal stresses, a duct arrangement is provided which selectively directs hot gases from the turbine combustor to the rim during the turbine start-up. The hot gases from the combustor serve to heat the rim, and thus decease the start-up period necessary to bring the temperature profile of the rotor into the operating temperature range. After the start-up period, the duct arrangement is then used to direct cool gases from the turbine compressor to the rim of the rotor in order to maintain a lower rotor equilibrium temperature.

Abstract: A computerized system for translating a torch head tip at a constant travel speed along a contoured workpiece including a driven skate characterized by an elongated bed, a pair of independently pivotal trucks connected to the bed in supporting relation therewith and mounted on a contoured track of an arbitrary configuration in mutually spaced relation, an axially extensible torch head manipulator arm mounted on the bed of the carriage and projected perpendicularly from the midportion thereof and having a torch head mounted at its distal end, and a real-time computerized control drive subsystem to advance the skate along the track at a variable rate for maintaining a constant speed for the torch head tip and to position the torch axis relative to a preset angle to the workpiece.

Abstract: A traveling wave tube (TWT) has a slow wave structure (SWS) which is severed into two or more sections. A signal path, defined below, connects the end of an SWS section to the beginning of the following SWS section. The signal path comprises an impedance matching coupler (IMC), followed by an isolator, a variable phase shifter, and a second IMC. The aggregate band pass characteristic of the components in the signal path is chosen to reject, or strongly attenuate, all frequencies outside the desired operating frequency range of the TWT and yet pass, with minimal attenuation in the forward direction, all frequencies within the desired operating frequency range. The isolator is chosen to reject, or strongly attenuate, waves, of all frequencies, which propagate in the backward direction. The aggregate phase shift characteristic of the components in the signal path is chosen to apply signal power to the beginning of the following SWS section with the phase angle yielding maximum efficiency.

Abstract: Thermocouples of the present invention provide stability and performance reliability in systems involving high temperatures and vacuums by employing a bimetallic thermocouple sensor wherein each metal of the sensor is selected from a group of metals comprising molybdenum and iridium and alloys containing only those two metals. The molybdenum, iridium thermocouple sensor alloys provide bare metal thermocouple sensors having advantageous vapor pressure compatibilities and performance characteristics. The compatibility and physical characteristics of the thermocouple sensor alloys of the present invention result in improved emf, temperature properties and thermocouple hot junction performance. The thermocouples formed of the molybdenum, iridium alloys exhibit reliability and performance stability in systems involving high temperatures and vacuums and are adaptable to space propulsion and power systems and nuclear environments.

Abstract: There is disclosed an apparatus for measuring indicated mean effective pressure (IMEP) of an internal combustion piston or rotary engine or of an external combustion engine such as a stirling engine. An optical shaft encoder measures crankshaft angle of the engine. Changes in volume with respect to changes in crankangle of one or more cylinders (dV/d.theta.) is determined either empirically or algebraically from engine geometry and stored in a memory. As the crank angle changes, dV/d.theta. is read from the memory and multiplied by chamber or cylinder pressure. The product (P dV/d.theta.) is then added to the total previously accumulated in the cycle. Each time .theta. changes by an amount equal to delta .theta., the process is repeated. At the end of each engine cycle, the total is equal to the IMEP value for that cycle.

Abstract: An improved method of constructing a metal oxide semiconductor (MOS) device having multiple layers of metal deposited by D.C. magnetron sputtering at low D.C. voltages and low substrate temperatures provides multilevel interconnections and cross over between individual circuit elements in integrated circuits without significantly reducing the reliability or seriously affecting the yield.