[hnfhour]

Hello everyone!
I have recently started to approach CFD analysis.
I'm trying to simulate Vortex Induced Vibration around a cylinder using Fluent. Before running the moving cylinder simulation, I ran a stationary cylinder simulation with good results.
Now I would like to simulate the VIV on the cylinder. My intention was to use Dynamic Mesh, but I have some doubts about it. Ansys Fluent User's Guide says "You need to define the motion of the dynamic zones in your model. If the zone is a rigid body, you can use a profile or user-defined function (UDF) to define the motion of the rigid body or use the six DOF solver".
Does that mean I can only use the 6DOF solver without using any user defined functions (UDF)?
If so, what and how should I set?
Sorry for the question, I searched a lot on the web but couldn't find anything about it. If you also have any tutorials to recommend, they are welcome.

Thank you very much.

Best regards.

[karachun]

You can set 1DOF properties (translation or rotation in one direction) using the Fluent graphical interface.
If your cylinder have more than one DOF then you should write and compile UDF with these properties (mass, moment of inertia, stiffness, etc.).

[hnfhour]

Originally Posted by karachun

You can set 1DOF properties (translation or rotation in one direction) using the Fluent graphical interface.
If your cylinder have more than one DOF then you should write and compile UDF with these properties (mass, moment of inertia, stiffness, etc.).

Thanks karachun for your reply. However, I continue to have problems. First I can't see the preview mesh motion, second thing during the simulation I got the error message "Update-Dynamic-Mesh failed. Negative cell volume detected". Also I was wondering when I define the dynamic mesh zones should I define my cylinder as rigid body and the surrounding domain as deforming?