Dynamic mesh in axisymmetric modeling
 

Hello all
I tryed to model the oscillating piston in a cylinder using dynamic mesh option.
because of small gap between cylinder and piston I can not used the 3D model due to increasing the number of mesh. so I used 2D-axisymmetric model. but when Fluent want to update the mesh with remeshing option the axis is not deformed and the nagative volume error is shown.
can any one help me?
Do I need another UDF to deform the axis?
Ps.: Negative volume occures in the contraction side of axis.
Contraction side picture is attached.

Did you solve this. I'm also having the same issue in a different geometry