Progress towards an open-source eigenvalue solver for free-boundary MHD stability

Abstract

Analysis of MHD stability in stellarators is analytically and computationally complex; while analytic figures of merit can provide physical insight into the stability properties of an equilibrium, more precise stability computations are necessary for improved stellarator optimization. This work makes significant progress towards extending an MHD stability eigenvalue solver in the DESC stellarator optimization suite to consider stability to external modes. Numerical results from the MHD stability eigenvalue solver are then compared to analytic results for a simple test case, validating the eigenvalue solver and its extension to external modes.