DOE/JPL Advanced Thermionic Technology Program. Progress report No. 40, July-August-September 1979

Technical Report · Mon Jan 01 00:00:00 EST 1979

DOI:https://doi.org/10.2172/5776844· OSTI ID:5776844

The primary long-term goal of the DOE effort at Thermo Electron Corporation is to improve TEC performance to the level that thermionic topping of fossil fuel steam powerplants becomes technically possible and economically attractive. The focus of the JPL program is to develop thermionic conversion technology appropriate for nuclear electric propulsion (NEP) missions. This report covers progress made during the three-month period from July through September 1979. During this period, significant accomplishments in the DOE program include: (1) Demonstration of 2300 hours of stable operation (Silicon Carbide Converter No. 1) in a combustion environment at emitter temperatures at, or above, 1600 K. This test is continuing. (2) Fabrication of two leaktight composite CVD (SiC/C/W) hot shell-emitter structures two inches in diameter. (3) Reproduction of W(100)/O/Zr emitter work function obtained at the Oregon Graduate Center. (4) Formation of an analytical model of the ignited mode thermionic diode which predicts the operating conditions associated with the onset of a double sheath at the emitter. Significant accomplishments in the JPL program include: (1) Demonstration of oxygen enhancement of a molybdenum emitter from a tungsten oxide collector. (2) Development of a technique for casting sapphire prototypic of NEP thermionic reactor system design. (3) Development of a technique for bonding lanthanum hexaboride to rhenium that was stable for 150 hours at temperatures ranging between 1600 and 1700 K. (4) Formulation of an assembly procedure for fabricating thermionic converters on an emitter heat pipe. (WHK)

• Research Organization: Thermo Electron Corp., Waltham, MA (USA)
• DOE Contract Number: EY-76-C-02-3056
• OSTI ID: 5776844
• Report Number(s): COO-3056-42
• Country of Publication: United States
• Language: English

Related Subjects

30 DIRECT ENERGY CONVERSION
THERMIONIC CONVERTERS
RESEARCH PROGRAMS
BONDING
FABRICATION
FOSSIL-FUEL POWER PLANTS
HEAT PIPES
LANTHANUM BORIDES
MOLYBDENUM
PERFORMANCE TESTING
PLASMA SHEATH
PROPULSION REACTORS
THERMIONIC COLLECTORS
THERMIONIC EMITTERS
THERMIONIC REACTORS
TOPPING CYCLES
TUNGSTEN OXIDES
WORK FUNCTIONS
BORIDES
BORON COMPOUNDS
CHALCOGENIDES
DIRECT ENERGY CONVERTERS
ELEMENTS
JOINING
LANTHANUM COMPOUNDS
METALS
OXIDES
OXYGEN COMPOUNDS
POWER PLANTS
POWER REACTORS
RARE EARTH COMPOUNDS
REACTORS
REFRACTORY METALS
TESTING
THERMAL POWER PLANTS
TRANSITION ELEMENT COMPOUNDS
TRANSITION ELEMENTS
TUNGSTEN COMPOUNDS
NESDPS Office of Nuclear Energy Space and Defense Power Systems
300401* - Thermionic Converters- Design & Development
300402 - Thermionic Converters- Performance & Testing
300403 - Thermionic Converters- Materials
Components
& Auxiliaries