Hi ! I am using fluent's 6 dof code in a model to simulate the trajectory of a small block inside a wind tunnel.I used unstructred nodes for meshing the geometry. I calculated the steady state conditions and then i turned on the unsteady and dynamic mesh modes. when i try to solve the mesh motion i am getting a -ve volume error and i got this message in the console window.

Mesh Statistics: Min Volume =-1.17434e-10 Max Volume = 9.95522e-02 Warning: negative cell volume detected! Error: Preview-Dynamic-Mesh failed Error Object: ()

I tried different time step size but still didn't work. can somone help me to solve this. Thanks in advance.

I would advice you to re-look at your dynamic zones. You can start with defining the block as rigid and the rest of the zones as dynamic.

Thanks for replying me manoj. Let me try that and let you know that works or not. I thought to get rid of the -ve volume we have to play with time step size and cell height. But it didn't worked for me. Anyways i will try what you said and thanks again.