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-   -   floating point exception? (http://www.cfd-online.com/Forums/star-ccm/74325-floating-point-exception.html)

syd March 30, 2010 07:22

floating point exception?
 
What's the meaning of "floating point exception"?

I set up a volume mesh and tried to run the solution: at this point, I got an error message about "154 negative volume cells", so I removed them with "Region->remove invalid cells".

After that I tried again to run the solution, but the message of the floating point exception appeared, without running any iteration...

Do you have any ideas of what the problem could be?

thank you!

Vinicius March 30, 2010 09:22

Hi,

Your simulation is diverging, this is the "meaning" of the floating point exception. One of its causes could be poor mesh quality. If you are using the polyhedral mesh, be sure that the surface mesh has a good quality and try to turn on the "Cell quality remediation" model in your physics continua. Also try to make another mesh, taking care at regions that have complex geometry or curvature.

Hope it helps,

Vinicius

Paulh March 30, 2010 14:18

You might also want to look for any non-contiguous regions. Chuncks of cells separated from the main Region will cause the solver to crash pretty quick.

nomad April 20, 2010 18:55

As a last resort, run a mem test on your RAM. Bad ram leads to round-off errors in the iteration results, that, over time, results in diverging trends.


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