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DOE OSTI · 23203903

Recent progress on the APOLLO3 calculation scheme for the FLUOLE2 experiment

Bertonazzi, R.·Ammar, K.·Gerard-Castaing, N.·Bourganel, S.
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Abstract

Studies of the neutron fluence on reactor pressure vessel and the correlated reactor lifetime issues require very good knowledge of the neutron source distribution in the reactor core and especially in the peripheral region. The FLUOLE2 experiment offers an appropriate starting configuration to investigate the possibility of using the APOLLO3 deterministic code with a two-step calculation scheme. It enables us to calculate a pin-by-pin neutron source distribution in the core, then to carry out the neutron propagation from the core to neutron detectors. In this paper, we focus on a calculation scheme dedicated to the determination of core neutron source distribution using APOLLO3 with the SHEM281 energy mesh, a Method of Characteristics (MOC) to solve the transport equation for the lattice computation step and a 20-groups 3D computation using the MINARET SN solver of APOLLO3. Reactivity and pin-by-pin reaction rate results have been analyzed. Results obtained with both lattice and core computations show a good agreement with those produced through a reference calculation using the TRIPOLI-4 Monte Carlo transport code. (authors)

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTSA CODESBENCHMARKSCOMPUTERIZED SIMULATIONEOLE REACTORNEUTRON FLUXT CODESTHREE-DIMENSIONAL CALCULATIONSVALIDATION

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Bertonazzi, R., Ammar, K., Gerard-Castaing, N., Bourganel, S.. 2022-07-01. Recent progress on the APOLLO3 calculation scheme for the FLUOLE2 experiment. https://doi.org/10.13182/physor22-37617

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