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Old   November 12, 2011, 18:50
Default How to visualize highly distorted mesh
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Elaine
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I am running 2 way FSI simulations and my simulation crashed as I lower my young modulus from 1e7 to 1e5. (1e7 worked but 1e5 crashed). The error is failure in reading mesh displacement, because of highly distorted elements. I wonder how can I visualize and check the region where the mesh distorted/collapsed to see how I can improve the mesh to improve the results. I read the CFD post manual but it is unclear how I can visualize and fix the mesh.

Thanks a lot!
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Old   November 13, 2011, 17:55
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Glenn Horrocks
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ghorrocks is a jewel in the roughghorrocks is a jewel in the roughghorrocks is a jewel in the rough
So is your question how do we view the mesh, or how do I see what is happening to find the problem area?
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Old   November 13, 2011, 18:18
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Yes. I want to know where is the location of the problematic area and what is causing the problem. Thanks!
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Old   November 13, 2011, 19:19
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ghorrocks is a jewel in the roughghorrocks is a jewel in the roughghorrocks is a jewel in the rough
If the run crashed before it wrote an output file then re-run it with a finer time step and saving an output file every time step. Hopefully that can capture the mesh motion enough that you can pick what went wonky.
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Old   November 13, 2011, 19:23
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Thanks ghorrocks. The funny thing is when I reduce the time step the simulation tends to crash and stop at earlier time step than using a coarser time step.
Also, in some cases the simulation just crashed at the first time step before writing any output file.
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Old   November 13, 2011, 19:28
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ghorrocks is a jewel in the roughghorrocks is a jewel in the roughghorrocks is a jewel in the rough
Then your model is highly unstable. I would use a E which is more likely to work (maybe 1e6?) and that might give you a clue as to where the problem is.
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Old   November 13, 2011, 19:31
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Cool~ Thank you very much! I will try it out.
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