Towards Digital Twins of Fusion Systems

Bridging the gap to next-step devices – while saving valuable time and resources – requires more than semi-empirical models, which struggle to predict plasma behavior in unexplored parameter regimes. Instead, validated simulation tools are essential, leveraging high-fidelity exascale computing and multi-fidelity models, including AI-based surrogates. To address these challenges, the “EUROfusion Theory and Advanced Simulation Coordination (E-TASC)” initiative was launched in 2021. It includes 15 TSVV (Theory, Simulation, Verification, and Validation) projects supported by five Advanced Computing Hubs. This “team of teams” has made substantial progress toward developing digital twins of fusion systems, with key scientific achievements to be presented in the paper. This includes the following topical areas: core performance in burning plasmas, magnetohydrodynamic transients, L-H transitions and ELM-free regimes, plasma exhaust, and plasma-wall interactions – with applications to both tokamaks and stellarators.