Qualification of Aster-code for the simulation of two-phase flows in porous media. application to Mascilia experiment

Within the framework of the nuclear waste storage in deep geological layers, the behavior of the saturated grounds in contact with the heating waste package is studied to ensure the short, average and long-term safety of the installation. However, experiments in geological ground, including heterogeneities, difficult to characterize, take a long time and are expensive. Therefore, the numerical simulation, which is a powerful tool to study the storage behavior versus space and time, became impossible to circumvent in order to analyze the radioactive waste management in porous media. In that prospect, the Thermo-Hydro-Mechanics (THM) modules of Code Aster were complemented by a two-phase thermal-hydraulics model, devoted to porous media. Such new developments intended to simulate the physical phenomena of un-saturation and re-saturation that occur in porous, permeable and initially saturated media, representative of worked engineer barriers or rock host. The concerned application is related to the storage of long-lived nuclear waste in deep geological layers. (authors)