An approach to multiscale modeling plasma surface interactions in tungsten, with a framework for uncertainty quantification

The presentation began with a view of an information-passing multiscale materials modeling approach, which is hierarchical in nature and integrates ab initio electronic structure calculations, molecular dynamics (MD) simulations, kinetic Monte Carlo (KMC), and kinetic reaction-diffusion rate theory simulations with thermodynamics and kinetics through the passing of information about the controlling physical mechanisms over the relevant length and time scales to model the fates of gas atoms and defects relevant to plasma surface interactions. The presentation then summarized observations from large-scale MD simulations elucidate the mechanisms of helium behavior following implantation into tungsten that are likely responsible for the early stages of tungsten surface evolution leading to the nanometer-scale fuzz, as well as have the potential to significantly modify tritium retention behavior.