Validation of SARAX code system using the SFR operational tests

Abstract This paper introduces extended validation works on SARAX code based on the hot state data of two SFRs, the JOYO and Phenix reactors. Compared with the previous validation based on the zero-power physical tests, these validation cases challenge the code because the calculation should consider more under the operational condition, including the fuel depletion, temperature effect and geometry expansion. Besides, more computational assumptions are discussed in this paper, which contains approximation of constant microscopic cross-sections, sensitivity to different depletion chain and so on. The isothermal temperature effect and burnup reactivity swing calculation were validated using the JOYO reactor and the control rod worth were validated based on the withdrawal tests in the Phenix final tests. The results show that SARAX code has good accuracy in simulating the SFR in the hot states. The neutronic parameters such as reactivity, control rod worth, and power distribution agreed well with the experimental data.