UDF to replace mesh
 

I am trying to simulate a model in FLUENT that the geometry shape is varying by time. I was wondering can I generate different geometry/mesh each time step and subsequently replace the new mesh each time steps? In fact, in the dynamic mesh events, there is option can manually define to replace the mesh in given time but I want to know can I use a UDF to do it automatically (i.e, load the new prepared geometry with new mesh each time step)?