Ansys Polyflow allows you to model a liquid with free surfaces using a so-called volume of fluid (VOF) technique for 2D and 3D problems. The VOF model is strictly an Eulerian formulation; this is in contrast to the combined formulation used in the Arbitrary Lagrangian-Eulerian (ALE) approach, which is the other means of simulating a free surface in Ansys Polyflow.

The VOF model does not require remeshing. Because the numerical technique used for the VOF model does not need to reconstruct the interface (by splines or similar methods) or compute distances between a point and a line or a surface, it is more general and has less limitations than regularly used geometry-based algorithms.