Minisymposium Presentation

Future developments towards magnetic confinement fusion energy depend on the understanding of turbulent transport in the edge and scrape-off layer (SOL). Gyrokinetic simulations are among the main tools used to improve our understanding of turbulence in the edge and SOL. Such global, high fidelity simulations provide an accurate description of the relevant physics, however are also highly expensive in terms of computational costs, even when simulating small machines. Approaching reactor relevant, large-scale machines not only increases the computational size drastically, but also imposes new challenges in terms of physics. In this talk we present an overview of the recent progress with the gyrokinetic turbulence code GENE-X, focusing on physical and computational challenges. GENE-X is an Eulerian-type "continuum" code that solves the collisional, full-f, electromagnetic, gyrokinetic Vlasov-Maxwell system on a grid. It is especially targeted towards edge and SOL simulations including the magnetic X-point, using the flux-coordinate independent (FCI) approach. To bridge the gap between simulations of small experiments and future reactors, we pursue two approaches. First, the code is ported to GPUs and, second, we implement an optimized spectral velocity space discretization. These improvements allow the GENE-X code to perform simulations of turbulence in large-scale fusion devices.