Analysis of Differences in Void Coefficient Predictions for Mixed-Oxide-Fueled Tight-Pitch Light Water Reactor Cells

Journal Article · Mon May 15 04:00:00 EDT 2000 · Nuclear Science and Engineering

OSTI ID:20804631

Unesaki, Hironobu ^[1]; Shiroya, Seiji ^[1]; Kanda, Keiji ^[1]; Cathalau, Stephane ^[2]; Carre, Franck-Olivier ^[2]; Aizawa, Otohiko ^[3]; Takeda, Toshikazu ^[4]

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1. Kyoto University (Japan)
2. Commissariat a l'Energie Atomique (France)
3. Musashi Institute of Technology (Japan)
4. Osaka University (Japan)

Analysis of the benchmark problems on the void coefficient of mixed-oxide (MOX)-fueled tight-pitch cells has been performed using the Japanese SRAC code system with the JENDL-3.2 library and the French APOLLO-2 code with the CEA93 library based on JEF-2.2. The benchmark problems have been specified to investigate the physical phenomena occurring during the progressive voidage of MOX-fueled tight-pitch lattices, such as high conversion light water reactor lattices, and to evaluate the impact of nuclear data and calculational methods. Despite the most recently compiled nuclear data libraries and the sophisticated calculation schemes employed in both code systems, the k{sub {infinity}} and void reactivity values obtained by the two code systems show considerable discrepancy especially in the highly voided state. The discrepancy of k{sub {infinity}} values shows an obvious dependence on void fraction and also has been shown to be sensitive to the isotopic composition of plutonium. The observed discrepancies are analyzed by being decomposed into contributing isotopes and reactions and have been shown to be caused by a complicated balance of both negative and positive components, which are mainly attributable to differences in a limited number of isotopes including {sup 239}Pu, {sup 241}Pu, {sup 16}O, and stainless steel.

• OSTI ID: 20804631
• Journal Information: Nuclear Science and Engineering, Journal Name: Nuclear Science and Engineering Journal Issue: 1 Vol. 135; ISSN NSENAO; ISSN 0029-5639
• Country of Publication: United States
• Language: English

Related Subjects

73 NUCLEAR PHYSICS AND RADIATION PHYSICS
A CODES
BENCHMARKS
CONVERSION
ISOTOPE RATIO
MIXED OXIDE FUELS
NUCLEAR DATA COLLECTIONS
OXIDES
OXYGEN 16
PLUTONIUM
PLUTONIUM 239
PLUTONIUM 241
RADIATION TRANSPORT
REACTIVITY
STAINLESS STEELS
VOID COEFFICIENT
VOID FRACTION
VOIDS
WATER COOLED REACTORS
WATER MODERATED REACTORS