Edge Fluid Turbulence Simulations of Stellarators With GRILLIX

The edge fluid turbulence code GRILLIX has recently been extended from axisymmetric tokamak geometries to support 3D stellarator configurations. Following successful proof‐of‐principle simulations published in Stegmeir et al., we present here a comprehensive simulation of the Wendelstein 7‐AS stellarator. After the implementation of source terms, we carried out simulations over a physical time span of ms, during which the turbulence evolved into a saturated state. The simulation is analyzed, revealing that the turbulence is of drift‐wave nature. The simulation results are placed in the context of typical experimental measurements and found to be consistent in many important aspects. Furthermore, to broaden its applicability, GRILLIX has been coupled with the FLARE library, a magnetic field line reconstruction tool that enables the integration of a wide range of stellarator geometries—including Wendelstein 7‐X. To demonstrate feasibility, a proof‐of‐principle simulation is performed in Wendelstein 7‐X geometry at realistic plasma parameters. While this initial simulation avoids the inclusion of island divertors, the integration of such divertor structures is ongoing.