| Autor: |
Yun Long, Siefken, Larry J., Hejzlar, Pavel, Loewen, Eric P., Hohorst, Judith K., MacDonald, Philip E., Kazimi, Mujid S. |
| Předmět: |
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| Zdroj: |
Nuclear Technology; Jul2004, Vol. 147 Issue 1, p120-139, 20p, 4 Diagrams, 4 Charts, 16 Graphs |
| Abstrakt: |
The thermal, mechanical, and chemical behavior of both thorium and uranium dioxide (ThO2-UO2) and thorium and plutonium dioxide (ThO2-PuO2)-based fuels during in-service and hypothetical accident conditions in light water reactors (LWRs) is described. These fuels offer the possibility for increased proliferation resistance and a reduction in the stockpile of weapons-grade and reactor-grade PuO2 as well as being a more stable waste form. The behavior is described for three different designs of ThO2-based fuels: a homogeneous mixture of ThO2-UO2, a microheterogeneous arrangement of the ThO2 and UO2, and a homogeneous mixture of ThO2-PuO2. The behavior was calculated with widely known LWR analysis tools extended for ThO2-based fuels: (a) MATPRO for calculating material properties, (b) FRAPCON-3 for calculating in-service fuel temperature and fission-gas release, (c) VIPRE-01 for calculating the possibility for departure from nucleate boiling, (d) HEATING7 for calculating in-service two-dimensional temperature distributions in microheterogeneous fuel, (e) SCDAP/RELAP5-3D for calculating the transient reactor system behavior and fuel behavior during loss-of-coolant accidents, and (f) FRAP- T6 for calculating the vulnerability of the cladding to cracking due to swelling of the fuel during hypothetical reactivity-initiated accidents. The analytical tools accounted for the following differences in ThO2-based fuels relative to 100% UO2fuel: (a) higher thermal conductivity, lower density and volumetric heat capacity, less thermal expansion, and higher melting point; (b) higher fission-gas production for 233U fission than 235U fission, but a lower gas diffusion coefficient in the ThO2 than in the UO2; (c) less plutonium accumulation at the ... [ABSTRACT FROM AUTHOR] |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
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