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Changing mesh size for independency test

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Old   August 23, 2009, 21:05
Default Changing mesh size for independency test
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Hi all
I have 6 mm artery witn aneurysm and I want to do mesh independency test. I chose 0.4 mm mesh size for artery and 0.2 mm for aneurysm with scale factor 1 and 3 layers prism mesh which gives me around 400000 elements. I 'm not really sure how should I change the mesh size for independency test. I tried 1000 times changing parameters and check the total pressure difference at inlet and outlet. but still can not get a smooth line for this test. My convergence with residual 10-5 is good and I have no idea what's wrong. I even try until 1000000 element but every time the answer is different. Any suggestion would be appreciated.


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Old   August 27, 2009, 13:55
Default Scale Factor...
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I am not sure about your results, but if we assume that your bocos and solver setup are all correct, it suggests your mesh is not fine enough. I would probably check your solver setup before I tried the larger mesh. You may also want a much thicker boundary layer for your viscous fluid (3 layers may not be enough). You could also try Hexa instead of Tetra/prism.

In more familiar territory (for me any way), I can say that an easy way to adjust your mesh size is to adjust only the Scale factor...

All other sizes are multiplied by this, so you can adjust all your sizes by 25% simply by changing this number from 1 to 1.25...
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