Enhancing Boundary Plasma Simulations: Key Advances from the ABOUND SciDAC Project*

The ABOUND SciDAC project has advanced the BOUT++ framework, enhancing understanding and control of Edge Localized Modes (ELMs) and other critical plasma phenomena. Key improvements include efficient plasma simulations, insights into ELM dynamics through zonal flows and fields, and enabling simulations with the HYPRE 3D solver for low-n toroidal mode numbers. BOUT++ simulations revealed the connection between upstream turbulence properties and downstream divertor heat flux width for DIII-D QH-mode experiments. Molecular simulations show plasma detachment at the divertor target exhibits hysteresis bifurcation and higher recombination temperatures due to molecular processes. We are developing code-coupling of BOUT++ with GEM and SOLPS-ITER for integrated simulations, exploring gyrokinetic pedestal micro-turbulence in small/grassy ELM regimes with GEM, and examining divertor-plasma detachment under negative triangularity using SOLPS-ITER. Computational speed has increased with GPU acceleration. Advanced algorithms have enhanced temporal resolution using SUNDIALS with multi-rate methods, while integration with ADIOS2 has optimized data management. Enhanced visualization techniques have enabled clearer interpretations of complex datasets and physics mode structures.These efforts have improved the predictive capabilities and efficiency of ABOUND codes, influencing future tokamak design and operations for optimized plasma confinement and exhaust solutions.