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-   -   refine mesh inside a block, water surface not smooth anymore (http://www.cfd-online.com/Forums/star-ccm/123784-refine-mesh-inside-block-water-surface-not-smooth-anymore.html)

JohnAB September 20, 2013 17:13

refine mesh inside a block, water surface not smooth anymore
 
Hello,

I want to model the water surface in a towing tank system and I have the following issue:

When, in the middle of my simulation, I pause to add a block and refine the mesh within that block, the water surface then appears "broken" and definitely not smooth anymore.
When I resume simulation, this does not help and the surface never gets smooth anymore (inside this new block), even if I wait until my simulation is done, or even when I put like hundreds of iterations per time step. I still could not find a way to get everything smooth again after refining the mesh.

Does anyone have an idea about that ?

Thanks a lot!

lava12005 September 25, 2013 05:27

The 'broken' surface might be due to the method that CCM use in interpolating the value of the old mesh to the new mesh. I suspect the software take the face value of the old mesh, that is why it might be possible that the refined mesh looks 'broken' (correct me If I am wrong).

But I think this should not be an issue. Before you refined the surface, does the surface looks fine? Run more time step?

JohnAB October 4, 2013 13:53

lava,

Yes, before I refine the mesh, the surface is perfectly smooth (my mesh already is very fine, just not enough for what I want to catch). I then refine within the block and it immediatly turns out to be broken within that block (where I would have guessed that it would at least look as fine as it was before).
After that, I can run as many time steps I want, the smooth surface is never coming back within that block (outside of it, it is still perfectly fine).

The only solution I have found so far to refine my water surface is to refine the mesh and completely restart the simulation from the beginning...


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