WEB Frictionless motion of diffuse interfaces by sharp phase-field modeling
We investigate the influence of artificial grid friction in different phase-field models by considering the stationary motion of an interface between two phases at different bulk free energy levels. Following the striking idea of a Sharp Phase-Field Model (SPFM) from Finel et al. (Finel et al., 2018), we proof that restoring translational invariance indeed eliminates artificial grid friction effects during stationary interface propagation. Over a largely extended range of possible driving forces the theoretic interface velocities are reproduced by orders of magnitude more accurately, even if the diffuse interface profile is only marginally resolved by just one grid point. We propose a new variant of the SPFM, which restores translational invariance locally in the direction of interface motion. It is shown that, even for marginally resolved interface-profiles, the new SPFM variant provides frictionless motion for arbitrarily oriented planar interfaces. Finally, by considering thermal diffusion limited solidification, we demonstrate the capability of the SPFM-approach to also deal with inhomogeneous driving forces using a one-gird point interface resolution.