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Error in the solver !!! what does this mean...

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Old   September 3, 2010, 03:07
Default Error in the solver !!! what does this mean...
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Elena Cortin
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Hello

does anyone knows what is this error?

server error: a floating point exception has occured: floating point exception [invalid operation]. The specific cause cannot be identified. Potential causes may include : (a) solution divergence due to poor mesh quality, crude initiliazation, etc, or (b) errors in the user-defined code or field fuctions.


thanks
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Old   September 3, 2010, 06:15
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-use smaller time-step in your simulation (it have to work but time of computation will be longer)
-you can solve this problem on numerical way (underrelaxation factors etc.)
-improve mesh quality
-and/or chack (also possible) eg.capital font, sign (_ / -) in name of field function

regards
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Old   September 3, 2010, 08:34
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Quote:
Originally Posted by bengy View Post
-use smaller time-step in your simulation (it have to work but time of computation will be longer)
-you can solve this problem on numerical way (underrelaxation factors etc.)
-improve mesh quality
-and/or chack (also possible) eg.capital font, sign (_ / -) in name of field function

regards

well i do not have any sign (_\ etc)

i activate the ramp method to linear ramp
and apply a courant number 2

the mesh is ok

any other idea>????

thanks
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Old   September 3, 2010, 10:04
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courant number should be between 0.5 - 1.
let's try with smaller time step
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Old   September 4, 2010, 03:15
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Elena Cortin
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well i am having the same error

i am trying to do a transonic simulation of a missile model
and i follow the example but in 3d model, can i find any pre file with an axable like this????

i believe this is better option.

please any help on that
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Old   September 4, 2010, 05:10
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how large is your time step?
how many elements your mesh have?
where did you prepare mesh? (star-ccm+ or external soft?)
what kind of mesh do you have?(conformal or non-conformal?)
you have to sent more info about your simulation (physical model, expected value of solution-temp, velocity ec)
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Old   January 12, 2011, 08:42
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siamak rahimi ardkapan
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Divergence of the solution is the situation where cell residuals increase from one iteration to another. If left unchecked, this will eventually result in a floating point exception being reported.
I found it in the help of the software
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Old   January 15, 2011, 09:05
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Just go to the solver manager and tick the box "Temporary storage retained". This will prevent the solver from deleting temporay values when a iteration is complete.
With this option, you will have more field functions available, e.g. residuals, gradients etc...
So create a scene and check the residuals, it can give you an evidence where the problem could be located.
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