A modified phase field approximation for mean curvature flow with conservation of the volume

This paper is concerned with the motion of a time dependent hypersurface that evolves by mean curvature flow with a a volume constraint. Phase field approximation of this motion leads to the well known nonlocal Allen--Cahn equation. Here we propose a modified version of this equation, and we show that it has better volume preserving properties than the classical one, even in the presence of an additional forcing term.