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DOE OSTI · 23203946

CEFR simulation using diffusion code system RAST-F

Tran, T. Q.·Nguyen, T. D.C.·Lee, D.
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Abstract

In this study, the RAST-F code system, which is based on the two-step approach that couples a multi-group cross-section generation Monte-Carlo (MC) code and a multi-group nodal diffusion solver, was used for the neutronic simulation of the CEFR start-up experiments. The numerical solution of the RAST-F system was verified against the full core MC solution MCS at all control rods fully inserted and withdrawn states. The RAST-F solution of the selected experimental simulations was compared against the measurement data. A good agreement between RAST-F and MCS solutions was observed with less than 120 pcm discrepancies and 1.2% root-mean-square error in terms of k{sub eff} and power distribution, respectively. Meanwhile, the RAST-F result agreed well with the experimental data within two-sigma of experimental uncertainty. The good agreement of these results indicates that RAST-F can be used to neutronic steady-state simulations for small core-size SFR, which was challenged to deterministic code systems. (authors)

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21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTSCEFR REACTORCOMPUTERIZED SIMULATIONCONTROL ROD WORTHSCRITICALITYPOWER DISTRIBUTIONR CODESREACTIVITY

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BibTeXRIS

Tran, T. Q., Nguyen, T. D.C., Lee, D.. 2022-07-01. CEFR simulation using diffusion code system RAST-F. https://doi.org/10.13182/physor22-37558

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