A search for theories enabling analyses of spatial effects in highly coupled sfr cores

Abstract : SFR are a solution for the future of nuclear energy. The safety constraints brought by nowadays standards, especially about Sodium void reactivity effect, require core designs which are highly heterogeneous axially and rather flat. These features require an in depth analysis of spatial effects which involves appropriate methodologies. This paper presents a comparison of results obtained with first order perturbation, flux harmonics and coupled-core theories. This last one presents some advantages compared to the other ones for understanding the spatial effects of large SFR cores, and for propagating nuclear data uncertainties.