Overview of Research in the SciDAC Center for Simulation of Fusion Relevant RF Actuators*

An overview is given of research which has the goal of developing a predictive simulation capability of the self-consistent interaction of RF power with the scrape-off layer (SOL), including the effects of plasma sheaths, ponderomotive forces near an antenna, and turbulence and transport. This will make it possible to answer critical questions related to how RF power modifies properties of the SOL and how, in turn, the SOL affects the propagation and absorption of RF waves. Targeted problems include the impact of high power RF systems on plasma facing materials, including high-Z impurity sputtering and transport induced by large RF-induced sheath potentials, localized thermal loads, and antenna damage. In order to address the high geometric fidelity required to describe the 3D magnetic field and 3D solid geometry of the RF launching structures and the surrounding vacuum vessel the open-source scalable Modular Finite Element Framework (MFEM) is being utilized. The Parallel Unstructured Mesh Infrastructure (PUMI) is also being used in order to move to global solution domains, which are presently precluded by existing meshing approaches.