Recent Results from the SciDAC Center for Simulation of Fusion Relevant RF Actuators*

An overview is given of recent research results related to the self-consistent interaction of RF power with the scrape-off layer (SOL). We will discuss the development and application of RF wave solvers based on the open-source scalable Modular Finite Element Framework (MFEM), including the implementation of a RF sheath boundary, work on pre-conditioners for matrix solves, and grid adaptivity. We will discuss the development of a far-SOL fluid transport solver for equilibrium (Braginskii MFEM mini-app) and turbulent (SOLT-3D code based on BOUT$++)$ models. The turbulent transport model includes the presence of a RF ponderomotive force term which can be calculated directly from the results of the VSim FDTD plasma wave code. Results from full-wave RF solvers utilizing SOL turbulence data from an edge turbulence code will also be presented. Results in plasma-material-interactions will be presented on benchmarking of kinetic vs fluid sheath models, parameterization of a sub-grid RF sheath model, results from a 1D RF sputtering model, and results for fast ion impact at the plasma wall from an RF Monte Carlo code.