Improvements in simulation tools to be developed within the framework of the ASTRID project

International audienceThe ASTRID design comprises innovative features compared to past designs. The simulation tools being very important to support the ASTRID design option selection and to assist a robust Safety demonstration, the CEA and its industrial partners have launched a large program for developing a new generation of simulation tools. Within the framework of the ASTRID project, the strategy for simulation is to continuously improve the simulation tools and their verification and validation (VetV). Furthermore, this new generation of tools is implemented for the basic design of ASTRID in compliance with the regulatory and schedule requirements. Several examples of computation tool developments in the fields of neutronics, fuel behavior, core mechanics, thermal-hydraulics and severe accident analyses are given. The VetV process, described here for the core studies, is also carried out for others domains by the industrial partners.The approach is closely linked to the realization of the RandD experimental programs, aimed to complete the existing experimental data base and so to validate the new model developments and to decrease the calculation uncertainties. The development program of new simulation tools is ambitious in order to meet the challenges which arise from the innovative design options implemented in ASTRID and for the will to comply with the objectives of the 4th generation reactors