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Old   June 29, 2009, 09:09
Default Need help to determine whether Converged
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Edgard Espinosa
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Hi

I keep running the same model several times. Each time I change the mesh hoping to obtain converged results. However, I keep thinking that perhaps it won't converged or maybe I need more iterations. How many iterations should I at least give it to arrive to a conclusion?

http://i1009.photobucket.com/albums/...02/Results.jpg
http://i1009.photobucket.com/albums/af216/eespi002/Residuals.jpg

Please help.

Last edited by eespi002; June 29, 2009 at 09:11. Reason: Inserting images
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Old   June 29, 2009, 09:53
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Ling
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Hi eespi002,

If I am right, the first pic tells me you are doing a 3-D laminar flow simulation. And the second pic tells me you've done 300 iterations.

First, for a 3-D flow simulation, 300 iterations is way too less. try more.
Second, the continuity convergence looks pretty bad to me. If it drops at larger iteration numbers, it will be fine. Otherwise, you will have to find if you are using a right flow model. Check your Re number, see if it's a turbulent or laminar flow.

Good luck.


Quote:
Originally Posted by eespi002 View Post
Hi

I keep running the same model several times. Each time I change the mesh hoping to obtain converged results. However, I keep thinking that perhaps it won't converged or maybe I need more iterations. How many iterations should I at least give it to arrive to a conclusion?

http://i1009.photobucket.com/albums/...02/Results.jpg
http://i1009.photobucket.com/albums/af216/eespi002/Residuals.jpg

Please help.
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