Why is it hard to generate 3D MHD equilibria with smooth nested flux-surfaces ?

This talk was given at the 4th Asian-Pacific Conference on Plasma Physics on October 28 2020. I am sharing it here because it provides a rapid introduction to the business of MHD equilibria calculation. Abstract Renewed interest in stellarator design has sparked questions on the existence and accessibility of three-dimensional magneto-hydrodynamics (MHD) equilibria with “good” nested flux-surfaces. Several numerical tools exist to obtain three-dimensional MHD equilibria. These methods aspire to

Visualisation software for M3D-C1

M3D-C1 is the state-of-the-art for performing non-linear 3D resistive MHD simulations of tokamaks. I was using it to model VDE and disruptions during my postdoc at PPPL with more or less success. One really annoying thing was the lack of visualisation tools, especially for probing the 3D components of the plasma evolution. I thus developed a set of tools (Matlab package) to reconstruct the data from M3D-C1 native output (Finite