Global sensitivity analysis of a coupled multiphysics model to predict surface evolution in fusion plasma–surface interactions

We construct a global sensitivity analysis framework for coupled multiphysics model used to predict the changes in material properties and surface morphology of helium plasma-facing components future fusion reactors. The combines particle dynamics simulator F-TRIDYN, that predicts implantation profile, with cluster Xolotl, growth evolution subsurface gas bubbles. In order keep tractable, we first sparse, high-dimensional polynomial chaos expansion surrogate each output quantity interest, which allows efficient extraction information. is performed two problem settings: one ITER-like conditions, resembles conditions inside PISCES-A linear plasma device. present systematic comparison important parameters, both F-TRIDYN Xolotl isolation as well model, discuss physical interpretation these results.