Sensitivity analysis and similarity evaluation of sodium-cooled fast reactor in large size

Highlights: • The sensitivity of k_eff of parts of existing evaluated experiments is analyzed. • Different methods to distinguish the similar experiments are compared. • Similarity characteristics of sodium-cooled fast reactor are discussed. - Abstract: We conducted a validation of the newly developed SARAX code for the China Fast Reactor (CFR). Unlike the usual way to validate code using dedicated experimental data, we proposed and implemented a theoretical way using the existing experimental data. This paper introduced a method to select the suitable existing experiments, which are "similar" to the CFR's criticality characteristics. We based our method on the sensitivity and uncertainty (S&U) analysis and the similarity analysis. We analyzed different experiments and discussed different ways to distinguish these experiments. Our results showed that a large-size mixed-oxide-fueled experimental core was necessary to represent the critical characteristics of CFR for the code validation. The method using both sensitivity and covariance was better able to distinguish the difference between the objective core and the other cores.