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Old   November 11, 2009, 09:16
Default Conservation of mass
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karine
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Hello all,
i am a Fluent user.
We all know that the finite volume method is conservative
however, we can see that in many simulations we have small mass imbalance
Is that due to roundoff errors????
do FVM still conservative for non linear equations like NS?

when the simulation diverge, we can obtain sometimes an enormous mass imbalance....
Thanks for ure replies
Regards
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Old   November 11, 2009, 17:21
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sometimes the convergence criteria there isn't all. for example in the airfol tutorial if i don't remember badly; don't use this criteria but monitor mass flow in the outflow surface. i think that you change this and go on with the interetion the bilance of mass go down.
i hope that will be helpful
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Old   November 11, 2009, 21:00
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karine
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yes it was very useful
thanks comrade
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