HIGH-TEMPERATURE VAPORFILLED THERMIONIC CONVERTER. Final Technical Report, March 15, 1962 through September 15, 1963
ABS>The operating characteristics of plasma converters utilizing bare uranium--zirconium carbide as the emitting surface were determined as a function of operational lifetime. The emitter design was cylindrical in a size representative of that expected in a space thermionic reactor. The electrode spacing varied from 0.040 to 0.012 in. The converter performance was evaluated as a function of lifetime and, the failure mechanism on those converters that no longer demonstrated useful power levels was determined. An operational lifetime of 3,000 hr was considered a reasonable goal. Electrically heated, as opposed to fissionheated, converters were selected as the most economical method of fulfilling the objectives. Six converters were operated for over 6,000 hr at power levels of 10 to 40 watts (1 to 4 watts/cm/sup 2/) on a continuous- performance basis. A maximum power density of 6.8 watts/cm/sup 2/ was observed at an emitter temperature of 2,245 deg K. The optimum cesiumreservoir temperature for all converters tested occurred at 605 to 630 deg K. Collector-temperature optimization was not clearly established within the temperature range investigated. The performance of bare-carbide converters increases almost exponentially with increasing emitter temperature. Performance observations were made in the emitter-temperature range 1900 to 2400 deg K. Five of the six converters failed during operation owing to envelope leakage, resulting in the complete loss of cesium to the surrounding vacuum chamber. Despite the depletion of uranium from the bulk of the emitter, vacuum-emission currents measured pre- and post-test were nearly identical in magnitude. Both uranium and zirconium, evaporated from the emitter surface, were deposited on the collector. (auth)
- Research Organization:
- General Atomic Div., General Dynamics Corp., San Diego, Calif.
- NSA Number:
- NSA-18-009064
- OSTI ID:
- 4082239
- Report Number(s):
- GA-4012; RTD-TDR-63-4190
- Country of Publication:
- United States
- Language:
- English
Similar Records
PERFORMANCE AND ENERGY-TRANSFER MEASUREMENTS ON CYLINDRICAL CESIUM THERMIONIC CONVERTERS
OPERATING CHARACTERISTICS OF A CESIUM DIODE UTILIZING FISSION HEATING OF THE EMITTER
Related Subjects
CONVERSION
CURRENTS
CYLINDERS
DEPOSITS
DISTANCE
ELECTRODES
EMISSION
EVAPORATION
HEATING
HIGH TEMPERATURE
LIFETIME
LOSSES
LOW TEMPERATURE
MEASURED VALUES
NESDPS Office of Nuclear Energy Space and Defense Power Systems
OPERATION
PERFORMANCE
PHYSICS
PLANNING
PLASMA
POWER
QUANTITATIVE ANALYSIS
QUANTITY RATIO
SURFACES
TEMPERATURE
TESTING
THERMIONICS
URANIUM
URANIUM CARBIDES
VACUUM
VAPORS
ZIRCONIUM CARBIDES