The validation of simulation tools involves comparison with experience for all the quantities of interest related to reactor physics. In the frame of neutronics, this process makes use of national and international databases (IRPHE, ICSBEP) that offer a set of configurations on which these comparisons are possible. In order to ensure a high level of confidence of simulation tools for a specific target core design (industrial design, prototype, demonstrator,...) to be built, it is necessary to select the relevant experiments for validation. Up to now, this selection is made according to a criterion of “similarity” or “representativeness”. In practice, neutronic sensitivity coefficients can be used to build integral estimators or indicators that can help quantifying the degree of “similiarity” between two concepts or experiments.
The reduced number of estimators built with these sensitivities does not allow an “efficient” selection between several configurations. The present work does propose to characterize experiments using alternate estimators (to be defined) related, as close as possible, to the physical phenomena (slowing down of neutrons, neutron spectra, mean free paths, etc.) to improve the selection tools (such as NDAsT) and make it possible to better discriminate between the available experiments.
Once implemented, this new methodology should make it easier to identify phenomena that are not covered by existing databases. New experiments can then be considered to fill this gap and broaden the validation domain for the target concepts.
A specific application will be made on lead-cooled fast neutron reactors.