The testing of NRX/EST and NRX-A5.
Testing of NRX/EST and NRX-A5 with emphasis on startup capability, engine control and high temperature operation
ENGINE TESTING↗
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Results for “high operating temperature”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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High temperature materials study
High temperature operating electronic devices for vapor deposition reactor system
Baxter, R. D.↗
High-temperature-materials study
Chemical vapor deposition of aluminum phosphides onto single crystals of silicon and gallium arsenide for producing high temperature operating solid state electronic devices
Baxter, R. D.↗
Radiometric temperature reference
Radiometric Temperature Reference uses a thermistor as both a heating and sensing element to maintain its resistance at a preselected level to continuously control the power supplying it. The fixed infrared radiation level must be simple, rugged, and capable of high temperature operation.
Monford, L. G., Jr.↗
Development of ion implantation techniques for microelectronics
Ion implantation process for fabricating active devices in high bandgap semiconductor materials for high temperature operation
Dunlap, H. L.↗
Gallium phosphide devices for use at high temperatures.
Schottky barrier diodes for high temperature operation prepared on n type GaP single crystals, studying I-V and C-V characteristics
Nannichi, Y.↗
Inorganic bonding of semiconductor strain gages
Inorganic bonding materials minimize outgassing and improve electrical and mechanical properties of semiconductor strain-gage transducers in high-vacuum and high-temperature operations. The two basic methods described are ceramic-glass-bonding and metallic bond formation between the strain gage and the substrate.
Woodruff, N. L.↗
Improved insulating materials effective at extremely high temperatures
Wrapped molybdenum foil with silica fabric insulation and wrapped tantalum foil with carbon fabric insulation are usable to 1367 K and up to 2478 K, respectively, both offer marked space saving and efficiency in high temperature operations. Graph displays temperature profiles at end of firing period.
Carlson, L. W.↗
Effects of sublimation on silicon-germanium RTG performance
Performance of silicon-germanium thermoelement in RTG with sublimation at high operating temperatures
Source record↗
Advanced design concepts for high speed bearings
High speed roller bearing design with long fatigue life and weight reduction for high temperature operation in inert environment
Scibbe, H. W.↗
Air-atomizing splash-cone fuel nozzle reduces pollutant emissions from turbojet engines
Advantages of fuel nozzle over conventional pressure-atomizing fuel nozzles: simplicity of construction, ability to distribute fuel-air mixture uniformly across full height of combustor without using auxiliary air supply, reliability when using contaminated fuels, and durability of nozzle at high operating temperatures.
Ingebo, R. D.↗
Monel-shot and screen regenerators
Monel has been found to be ideal material for matrix of regenerators operating in temperature range of 325 K to 50 K. Two best shapes are as spheres or as wire mesh. For given size of regenerator, spherical shots are preferable for low-temperature operation. At high temperatures, mesh would be superior by virtue of its lower flow resistance.
Browning, C. W.↗
Photodiodes for ten micrometer laser communication systems
The performance is discussed of 10-micron mercury-cadmiumtelluride and lead-tin-telluride photodiodes in laser heterodyne communication systems. The dependence of detector quantum efficiency, resistance, frequency response, and signal-to-noise ratio on temperature, bias, and local oscillator power are examined. Included in the discussion is an analysis of the feasibility of high temperature operation, and ability of the detector to dissipate power to a heat sink is explored. Some aspects of direct detection response are considered and figures showing flux levels from a blackbody presented.
Cohen, S. C.↗
Steady-state heat transfer in transversely heated porous media with application to focused solar energy collectors
A fluid flowing in a porous medium heated transversely to the fluid flow is considered. This configuration is applicable to a focused solar energy collector for use in an electric power generating system. A fluidized bed can be regarded as a porous medium with special properties. The solutions presented are valid for describing the effectiveness of such a fluidized bed for collecting concentrated solar energy to heat the working fluid of a heat engine. Results indicate the advantage of high thermal conductivity in the transverse direction and high operating temperature of the porous medium.
Nichols, L. D.↗
The effects of aniline impurities on monopropellant hydrazine thruster performance
Both a 0.45-N and a 0.9-N thruster representative of the designs being flown on 3-axis stabilized spacecraft were used in testing various grades of hydrazine for the phenomenon of monopropellant hydrazine thruster catalyst bed poisoning. Both designs employed Shell 405 ABSG spontaneous catalyst. It is found that pulse shape distortion can be minimized, if not eliminated, by using aniline-free hydrazine. The mechanisms for both steady-state and pulse-mode performance loss are associated with the formation of a catalyst coke similar to the polycyclic aromatic poisons encountered in the petroleum industry. These poisoning mechanisms are reversible, with high-temperature operation being required to drive off the aniline coke deposits. It is recommended that a purified-grade hydrazine be considered for any mission that imposes operational conditions on a thruster which can result in aniline-induced poisoning of the catalyst bed.
Holcomb, L.↗
Bimetallic junctions
The formation of voids through interdiffusion in bimetallic welded structures exposed to high operating temperatures is inhibited by utilizing an alloy of the parent materials in the junction of the parent materials or by preannealing the junction at an ultrahigh temperature. These methods are also used to reduce the concentration gradient of a hardening agent.
Arcella, F. G.↗
Advanced thermoelectric material development at JPL
A large number of planetary missions under consideration for the next two decades will be using radioisotope thermoelectric generators to provide the necessary spacecraft electrical power. Performance, reliability, lifetime and cost of these RTGs are expected to be more demanding and will require the development of advanced thermoelectric materials. An advanced thermoelectric materials development program is being conducted by JPL and is the subject of this paper. Under this program, alloys of rare earth chalcogenides have been synthesized and their thermoelectric properties evaluated. The selection of specific compounds on which the program is currently concentrating is influenced by criteria such as low thermal conductivity, reasonably high operating temperatures (not less than 1000 C) and stability of the compounds. The paper discusses the rationale, approach and current status of the program. In addition, the thermoelectric and thermophysical property measurement used to evaluate the materials are described. The preliminary results and analysis of these experimental data are also given.
Stapfer, G.↗
NASA-OAST/JPL high efficiency thermionic conversion studies
Efforts were made to develop a thermionic energy conversion TEC technology appropriate for nuclear electric propulsion missions. This space TEC effort was complementary to the terrestrial TEC studies sponsored by the Department of Energy which had the goal of topping fossil fuel power plants. Thermionic energy conversion was a primary conversion option for space reactors because of its: (1) high operating temperature; (2) lack of moving parts; (3) modularity; (4) established technology; and (5) development potential.
Source record↗