Overview of Research Results from the SciDAC Partnership for Simulation of Fusion Relevant RF Actuators

An overview is given of research related to the interaction of ion cyclotron range of frequency (ICRF) power with the tokamak scrape-off layer (SOL) and core. We discuss the development and application of the RF full-wave solver Stix and the more general FEM analysis platform Petra-M, both based on the Modular Finite Element Framework (MFEM), highlighting work on implementation of high-fidelity geometric descriptions of ICRF antennas in the NSTX-U and WEST Tokamaks, incorporation of nonlinear RF sheath boundary conditions, matrix pre-conditioners, and progress on implementation of our RF codes on GPU's. We will review progress on the development of a far-SOL fluid transport solver for equilibrium (the MAPS MFEM mini-app) and the study of RF ponderomotive force effects on the edge / SOL using a combined edge transport and RF solver model (UEDGE and Vorpal). Results for the interaction of RF power with metallic surfaces will be presented, including PIC simulations of the ion energy-angle distributions at ICRH antennas in RF sheaths as well as a description of an integrated workflow for RF impurity generation and transport. Finally, we will report progress on coupled Fokker Planck / full-wave simulations for ICRF using both continuum and particle-based approaches.