Originally Posted by Komon (Post 352632)

i suppose then the boundary you are trying to move is a wall (bottom of the cilinder). I used the given udf for a similar purpose, for moving a whole cilinder in a pool of liquid/another cilinder. the only problem I faced was the deformation of the interior mesh cells, which I could not get to split/grow together. however, the difference I see in your attempt is that the wall, which you are trying to move, is ''blocked'' by the wall, which resembles cilinder side surface. I didn't have that in my case.
I think you should also include this side wall and interior zone in the dynamic mesh and use ''deforming'' as a type. and then work around conditions you have available (remeshing and so on), which define when your cells grow together or separate.