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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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Circuit in which an emitter is maintained opposite a concentric collector and guard structure is achieved by matching the temperature and potential of the guard with that of the collector over the operating range. This control system is capable of handling up to 100 amperes in the guard circuit and 200 amperes in the collectors circuit.
Selection of high emittance coatings for nuclear space power plant radiators - characteristics of iron titanate, calcium titanate, and aluminum oxide-aluminum titanate coatings
Compilation of photographs and graphs relative to determining thermal emittance of refractory metals, oxides, carbides, and titanates
Thermal emittance of refractory metals, oxides, carbides, and titanates for determining materials for use in space radiators
Space-stable thermal control coating studies with low ratio of solar absorptance to infrared emittance
Three IBM 7094 computer. program used in the thermal design of spacecraft will be discussed. The first program is one used for integrating spectral reflectance or emittance. The second program calculates the percent time a satellite spends in the earth's shadow during a revolution about the earth. And the third program is called our General Space Thermal Program and is used to calculate satellite temperatures throughout a revolution about the earth.
An IBM 7094, three dimensional, heat transfer program for satellite application is discussed. The program may be applied to all phases of spacecraft life, from launch to orbital quasi-steady state. Launch phase heating includes inputs by radiation from the hot fairing and free molecule flow heating after nose cone ejection. Orbital heat fluxes are accounted for by direct sunlight, earth-reflected sunlight, and earth-emitted input to the satellite. Internal heat exchange by conduction and radiation is determined, provided the appropriate conductances, radiation view factors, and effective emittances are known. A simplified analysis of an active thermal controlled spacecraft is incorporated into the program. One or more surfaces may contain shutter systems which have optical properties specified as a function of shutter opening. The program evaluates the feasibility of any configuration based upon maintaining an internal component within its tolerable temperature limits. The program employs a matrix inversion subroutine (Gauss Elimination Method) to solve the heat balance equations.
Temperature effect on stability of low solar absorptance to infrared emittance ratio coatings in space environment
Spacecraft thermal control surface damage by solar wind bombardment in hydrogen and helium plasmas, with measurements of solar spectral reflectance and thermal emittance
Uranium oxide as nuclear fuel when in contact with tungsten, molybdenum and tungsten-25 percent rhenium thermionic emitter
Validity of Kirchhoff law for apparent local spectral emittance and absorptance and total flux calculations for spacecraft cavities
Light activated low level switch consisting of electroluminescent GaAs p-n diode and double emitter silicon transistor
Normal emittance, reflectance and transmittance spectra of roughened rock and mineral surfaces from 8 to 25 micron wavelengths
Thermal emittance and reflectance of diffuse- bottomed, specular-walled groove in solar radiant- flux environment
Design of isotopic heat sources for space missions, noting atmospheric contamination when source burns on reentry, source and shield weights, sealing of alpha emitters, etc
Image contrast enhancing by matching spectral reflectance or emittance characteristics
Nonaccelerated electron beam envelope trajectory equation reformulated and solved allowing for finite emittance, space charge and self- magnetostatic forces
Graphite sensing disk for slug-type radiation calorimeters exhibits better performance at high temperatures than copper and nickel disks. The graphite is heat-soaked to stabilize its emittance and the thermocouple is protected from the graphite so repeated temperature cycling does not change its sensitivity.