Hi,

This VDO showed how to basically implement the moving mesh. I am not sure if you have seen it. If not, I hope it would help you.

http://www.youtube.com/watch?v=B6z8zVBtixk

hi

you can use moving mesh or deformed geometry physics.

https://www.comsol.com/model/modeling-deforming-meshes-30561

You have several solutions to this issue:

1-Adding "Moving Mesh" in the "Definitions" part.

2-Using "Phase Field (pf)" or "Level Set (ls)" interface.

3-...

But you should be aware that in some cases, related multiphysics items also should be enabled. For instance, "Two-Phase Flow, Phase Field" or "Wetted Wall".