a mesh motion question
 

Dear all,

I am working on a fsi case. The fluid model can work well before mesh motion is turned on. But if I used mesh motion, even without fsi, it got overflow quickly. Even if I use the result of static mesh case as the initial condition of mesh motion case, it still can not work.

Please help me if anyone know how to solve this problem. Thank you so much!

John

Some details of what you are doing might be useful......

There are two domains in my fluid model: water and porous. I used mesh motion in water domain. The problem is, even no fsi, just the fluid model itself, it gets overflow all the time. In the output file, all the mesh deformations are 0, which means the mesh is exactly the same with static mesh case.

So you are saying that you turn mesh motion off and it converges but you turn mesh motion on, but specify zero displacement it diverges?

Yes. It's so strange.

Make your water slightly compressible.