Impact of nuclear data uncertainties on the reactivity of an AN ASTRID-like sodium fast reactor

The EU 7 th Framework Project ESNII+ was launched in 2013 in support of the initiative ESNII (European Sustainable Nuclear Industrial Initiative) whose purpose is to design, license, construct and begin the operation of the Sodium Fast Reactor Prototype, ASTRID, before 2025. An ASTRID-like core design has been analyzed (see other paper in this conference) and it was found to have a global negative reactivity feedback to sodium voiding. Taking into account the importance of feedback coefficients on core safety, the influence of the uncertainties in nuclear data should be assessed to have an exhaustive picture of the actual safety margins of ASTRID design. The objective of this work is to contribute to the improvement of the safety of ASTRID nuclear design by assessing different uncertainty propagation methodologies of the TSUNAMI-3D module of the SCALE system [ 1 ]. In this work, TSUNAMI-3D is applied to a pin-cell of the inner zone of the ASTRID core in order to select the optimal TSUNAMI-3D parameters. These parameters will be applied in future works to the Sensitivity and Uncertainty (S/U) analysis of the full core. (Author)