Dynamic Mesh Problem - please help!

Hila

Dear all,

I hope you'll be able to help me with my problem. My simulation includes a simple axisymmetric 2D geometry of a vortex ring apparatus (a cylinder with an opening). In order to induce radial motion of the cylinder walls I wrote a DEFINE_CG_MOTION udf file which was compiled and loaded successfully. In the dynamic mesh zone panel I hooked the udf file to the wall (rigid motion) and defined deforming type to the adjacent walls. In the dynamic mesh parameters panel I used relayering method since my grid has only quadrilateral cells. I've faced two main problems:

1. I cannot view the wall motion neither the mesh motion. The wall does not move and the mesh is not changed. Fluent does not report any error, it seems to work properly but I cannot identify any change to the grid/geometry.

2. When trying to save case/dat file (either by autosave and iterate or by marking the enable autosave in the mesh motion panel), Fluent reports error writing the data file:

"Error: get_udf_function: function wall_velocity::libudf has wrong type: 39!=46 Error Object: ()"

"Error writing: "C:\...(path name)…\....*.dat" Error Object: #f".

I will appreciate any help since I don't know what else should I do..

Hila.