This project involves development of a high-fidelity whole device model (WDM) of magnetically confined fusion plasmas, which is urgently needed to plan experiments on ITER and optimize the design of future next-step fusion facilities. These devices will operate under high-fusion-gain physics regimes never achieved by any of the current or past experiments, making advanced and predictive numerical simulation the best tool for the task.

The main driver is based on the coupling of two advanced and highly scalable gyrokinetic codes, XGC and GENE, where the former is a particle-in-cell code optimized for the treating the edge plasma while the latter is a continuum code optimized for the core. We will take advantage of the complementary nature of these two applications to build the most advanced and efficient whole device kinetic transport kernel for the WDM. A major part of the technical development work will target the coupling framework, which will be based on the high-performance ADIOS library with its state-of-the-art DataSpaces in-memory coupling capability. It will be further developed for exascale and optimized for the coupling of most of the physics modules that will operate at various space and time scales.

Argonne’s efforts will focus on the algorithms for this complex multiscale coupling, taking into account the evolution of the exascale hardware and software being developed by the co-design projects and other exascale-focused efforts.

The resulting exascale application will be unique in its computational capabilities and will have transformational impact for fusion science.