Speaker: Nathan Amrofel
Date: Thursday 15th of September 2022, 1:15 pm.
Abstract:
A full understanding of the migration behavior of corrosion gases in clay rock is of fundamental importance for the reliability of scenarios predicting the long-term evolution of geological repositories. Due to the low permeability of host clay rock, the produced gas will accumulate as a distinct phase until the pressure becomes large enough. The high pressure generated will desaturate the surrounding clay rock by displacement of pore water far along gas paths, but also by the diffusion of water vapor through the gas. In order to better understand the impact of key transport processes occurring in gas flow in clay material, a pore-scale numerical study taking into account the capillary-dominated two-phase flow, the diffusion of water vapor in the gas phase and specific features of nanoporous materials such as kelvin effect is proposed. The work has been carried out using the Smoothed Particle Hydrodynamics (SPH) method, a Lagrangian and meshless method which has emerged as an efficient and reliable tool for simulating complex fluid flows. A drying algorithm with Kelvin effect, which drives the thermodynamic equilibrium between the fluid phase and the gas phase at nanoscale, has been implemented in a two-phase flow SPH code, initially developed at IRSN.