Iterative solution techniques for hybrid finite-element spectral-element models

Hybrid finite-element (FE) spectral-element (SE) discretizations combine a FE model part represented by a system of equations with an SE model part solved by Fourier transform. Specialized iterative solution techniques are developed based on Schur complements, matrix-free techniques, fast Fourier transforms and domain-decomposition-type preconditioners. Numerical experiments, e.g., for a superconductive dipole magnet, indicate that hybrid FE-SE models equipped with these special solvers outperform their classical full FE counterparts.