Full multigrid for magnetostatics using unstructured and non-nested meshes

Adaptive mesh refinement and mesh enhancing techniques, commonly applied in electromagnetic finite element simulation, give raise to a hierarchy of nonnested unstructured grids. The application of geometrical multigrid is not straightforward. The prolongation operator is adapted to the particular properties of the mesh refinement. Anti-symmetric boundary conditions and nonlinear material characteristics are incorporated. The numerical experiment performed on the model of a synchronous machine shows optimal convergence for the proposed multigrid scheme whereas the convergence of classical nested multigrid becomes troublesome.