| Contents |
| Physically motivated energy functionals for phase field models often incorporate singular terms leading to degenerate nonlinear or nonsmooth problems. While its common to replace those terms by smooth approximations to avoid numerical difficulties, numerical examples shows that this has a strong impact on coarsening rates of solutions.
We present numerical methods for phase field models under the presence of singular or nonsmooth terms. Combining nonsmooth Newton and multigrid techniques those methods are robust with respect to the nonlinearity and exhibit mesh independence and global convergence. Efficiency and robustness are illustrated for multicomponent Cahn--Hilliard and Allen--Cahn equations with logarithmic and obstacle potentials. |
|