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February 29, 2008, 06:26 |
how to avoid self intersection:Proam
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#1 |
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Hi all,
I am getting self-intersection after generating the subsurface eventhough if i enable avoid self intersection in advanced options. The interesting thing is the self-intersections are not in the subsurface regions but some were in the model. How to avoid this error? |
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February 29, 2008, 14:04 |
Re: how to avoid self intersection:Proam
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#2 |
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Try doing it manually. Select the cells where the self intersecting is happening and change them to a different cell type. Then use the advanced options in the subsurface generation panel to set these cells at a diffent thickness.
Another way is to just set all cells at the lower value, but this will screw up more y+ values. Good luck, Tom |
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March 1, 2008, 10:03 |
Re: how to avoid self intersection:Proam
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#3 |
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hello Tom & all.
I have the same self-intersecting problem after the sub-surface generation. I have a duct model, in which i have a sharp corners. after sub surface generation i found that the subsurface is going up and intersecting with surface in the sharp corner. I have tried playing with advanced options and different cell thickness for the region where i am getting problem. but nothing works the way i excepted. The one way may be putting the intersecting region to no sub-surfrace. but that doesn't make any sense since the region is very critical to the flow. Do any one know, how to solve this.? Regards, nava |
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March 2, 2008, 21:13 |
Re: how to avoid self intersection:Proam
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#4 |
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Hi all,
Sometimes I also got the same self-intersection error although I knew my shell surface was clean. What I did was, I would do a surface check before I proceed to sub-surface generation. Then I find attach those self-intersection shell and re-create new shell on those area. * To find attached shell, I use this method 1. new vertex set -> cell set 2. new cell set -> vertex set any Hope this will help! Airfoil |
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March 3, 2008, 19:55 |
Re: how to avoid self intersection:Proam
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#5 |
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You can also plot a contour plot with surface+subsurface and by that plot you can find intersectiong cell (subsurface menu->Plot...->Subsurface and Thickness Contour). The you can try to remesh the intersecting zone of the surface and then doing a new subsurface or you can change cell type in that zone and create a subsurface with different wall tickness
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March 6, 2008, 05:23 |
Re: how to avoid self intersection:Proam
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#6 |
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In the Advanced Subsurface Options there are two parameters which can help with self intersection problem - number of iterations and relaxation factor.
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