TIME: 3:30 PM

LOCATION: GMCS 314

SPEAKER: Golo Wimmer, Los Alamos National Laboratory

ABSTRACT: The magnetohydrodynamic (MHD) equations possess a rich underlying structure, including the divergence-free condition of the magnetic field and balanced transfers between kinetic, internal and magnetic energy. Numerical methods that fail to preserve this structure may suffer from reduced accuracy or even instability, as well as biases in long-term simulations.

In this talk, we present a structure-preserving finite element discretization for MHD that maintains these structural properties. This is done while including transport stabilization, which is essential in low dissipation regimes and is often missing in structure preserving methods. As an example, we consider the discretization in the context of magnetic confinement fusion (MCF). We demonstrate how our framework supports both 2D axisymmetric simulations for stable plasma regimes and fully 3D simulations for capturing complex instabilities, while ensuring seamless transitions between 2D and 3D. Finally, we discuss ongoing work on efficient solver strategies and preconditioning, which in the context of MCF is largely related to stiffness arising from fast Alfvén waves.

BIO: Golo Wimmer is a research scientist with the Applied Mathematics and Plasma Physics Group at Los Alamos National Laboratory. He earned his PhD in Mathematics from the Department of Mathematics at Imperial College London in 2020, followed by a two-year postdoctoral position at Los Alamos. His research focuses on structure-preserving finite element methods, with applications in numerical weather prediction and magnetic confinement fusion (MCF). His broader interests include other challenging numerical aspects of MCF, such as the treatment of extremely anisotropic diffusion.

HOST: Valeria Barra