Assessment of SCALE capabilities for full core Monte Carlo burnup calculations of Sodium Fast Reactors

Within the framework of the Horizon-2020 ESFR-SMART project, and with the objective of assessing and improving computational tools for fast reactor neutronics calculations, this MSc Thesis originates. The main goal of this work is to assess the SCALE Code System capabilities for full core Monte Carlo transport/depletion calculations with continuous energy treatment. Depletion calculations are based on the coupling between neutron transport and inventory codes. Accuracy of the results depends, among others, on the code approximations and on the coupling method. In previous versions, SCALE Code System providedthe capability to carry out burnup calculations based on the deterministic approximation(NEWT code) for neutron transport in a coupled way with the inventory code ORIGEN. In recent releases SCALE has built-in the Monte Carlo KENO code for neutron transport on burnup calculations, both in multigroup and continuous energy. It is possible now to perform full core coupled KENO/ORIGEN calculations with SCALE. In this project, the applicability and limitations related to the use of this tool for SFR analysis are evaluated. For this purpose, SCALE results are compared to the ones provided by Serpent code. Firstly, a simplified 3-D pin-cell model is used in order to make an exhaustive analysis concerning multigroup applicability for fast spectrum and branching ratios and fission yields consideration. Likewise, an in-depth study of the differences between SCALE and Serpent will be performed by using this simplified model. Secondly, a full core model for ASTRID-like reactor is used. Taking into account the model heterogeneity, it is of interest to assess the computational resources required for the whole coupled transport/depletion problem. SCALE code, among others, will be applied to the ESFR design to be developed in the framework of ESFR-SMART project. Then, as a result of this MSc Thesis, it will be possible to know the SCALE limitations for once-through burnup calculations to be performed for the ESFR safety analysis.