Energy conversion research
Energy conversion research on alkali metal vapor, large nonequilibrium generator, and plasma instability
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Energy conversion research on alkali metal vapor, large nonequilibrium generator, and plasma instability
Differential Stark effect in second excited state of alkali metal atoms described, using electric field level crossing spectroscopy
Thermal accommodation coefficient measurements with rare gases and metals and alkali metal sets
Alkali metal Rankine cycle space power system component and systems design
The exchange current observed at porous metal electrodes on sodium or potassium beta -alumina solid electrolytes in alkali metal vapor is quantitatively modeled with a multi-step process with good agreement with experimental results.
Advanced Stirling Radioisotope Generator (ASRG) is an attractive energy system for select space missions, and with the addition of a VCHP, it becomes even more versatile. The ASRG is powered through thermal energy from decaying radioisotopes acting as General Purpose Heat Sources (GPHS). A Stirling engine converts the thermal energy to electrical energy and cools the GPHS [2]. The Stirling convertor must operate continuously to maintain acceptable temperatures of the GPHS and protect their cladding. The addition of alkali metal VCHP allows the Stirling to cycle on and off during a mission and can be used as a backup cooling system. The benefits of being able to turn the Stirling off are: allowing for a restart of the Stirling and reducing vibrations for sensitive measurements. The VCHP addition should also increase the efficiency of the Stirling by providing a uniform temperature distribution at the heat transfer interface into the heater head.
In order to model the lifetime of the electrochemical cell in an Alkali Metal Thermal to Electric Converter (AMTEC), studies of TiN Electrodes on Beta-alumina solid electrolytes (BASE) have been made to determine the performace parameters over time. The first of a series of experiments in which TiN electrodes are studied in a Vapor Exposure Test Cell is described here, with preliminary results from electrochemical measurements made on the cell. The TiN electrodes tested here perform well, with minimal degradation over 1000 hours of operation at 850 degree C.
The Sodium Exposure Test Cell (SETC) is a non-power producing cell which has been developed to evaluate and test components of the electrochemical cell in an Alkali Metal Thermal to Electric Converter.
Vortex magnetohydrodynamic power generator, alkali metal carbonates to seed combustion plasmas
High temperature materials in spacecraft propulsion devices and electrical power generation systems utilized because of their electronic work functions, thermoelectric properties and corrosion resistance to alkali metals
A leakproof seal secondary cell containing alkaline electrolytes was developed by bonding an alkali-resistant elastomer, such as neoprene, to metal contact surfaces. Test results of several different elastomers strongly indicate the feasibility of this sealing method.
Pair of encased low permeability hand gloves between which an inert gas circulates reduces dry box contamination. This innovation is applicable to dry boxes using radioactive and alkali metal compounds, submicron powders, and liquid metals.
Crystalline surface investigation - epitaxy of compound crystals influenced by radiation and of graphites on fluorites, interfacial energy and nucleation, monolayer metals, and alkali films
Polarized electrons produced by atomic beam apparatus - hyperfine structure intervals of alkali atoms
Dispersion-strengthened tantalum-base alloys possess high strength and good resistance to creep deformation at elevated temperatures in high vacuum environments. They also have ease of fabrication, good weldability, and corrosion resistance to molten alkali metals.
Smooth, unfoamed elastomer is unaffected by common acids, alkalies, and organic solvents. Its thermal stability, chemical resistance, and physical properties make it of interest for various applications.
Measurements of short term frequency stability using microwave pulsed induced emission in alkali vapors
Ionization studies dealing with ion source, emission contamination, and alkali desorption energies on polycrystalline refractory metals