A high performance spectral code for nonlinear MHD stability (Q1322997)

A new spectral code, NSTAB, has been developed to do nonlinear stability and equilibrium calculations for the magnetohydrodynamic (MHD) equations in three-dimensional toroidal geometries. The code has the resolution to test nonlinear stability by calculating bifurcated equilibria directly. NSTAB builds on the highly successful BETAS code, which applies the spectral method to a flux coordinate formulation of the variational principle associated with the MHD equilibrium equations.