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Meshing between two elipses

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Old   October 13, 2010, 03:29
Default Meshing between two elipses
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Hi , I´m doing the mesh between two elipse with boundary layer in the inner one.

I obtain the mesh of the pic below:



But the quality of the mesh is very bad(Skew>0.6).

Any suggestions ¿?
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Old   October 14, 2010, 01:40
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If your skewness is <0.8, it should be ok (for 2d, quad)
I assume your problem, is more on the aspect ratio (where it is refined). Then insert more nodes on the refined ellipse (the problem will be projected on the other ellispe, but as is it not refined, I assume it is not a point of interest for you)
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Old   October 14, 2010, 02:53
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I saw the skewness right now , and the problem is that I have a lot of mesh with a skew>=0.8 (the picture below)


If I insert more nodes to do the mesh I obtain exactly the same problem...
About the aspect ratio , how could I improve it¿?
Thanks in advance.
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Old   October 14, 2010, 02:58
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something is weird. I don't see why cells on the right have bad skewness.
Is it 2d or 3d?
Ca you post picture of skewness (from quality 0 till 1) with on (zx) plane (y pointing in your direction)
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Old   October 14, 2010, 03:12
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The problem is 2d , here the pics:



Skew from 0 to 1:

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Old   October 14, 2010, 03:16
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sorry I wanted a front view.
Try to remesh your domain by doubling counter nodes on smallest ellipse
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Old   October 14, 2010, 03:32
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Quote:
Originally Posted by -mAx- View Post
sorry I wanted a front view.
Try to remesh your domain by doubling counter nodes on smallest ellipse
The second one is a front view of two elipses.
The option of doubling the counter nodes doesnt work.
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Old   October 14, 2010, 04:10
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ah ok, I understand now.
doubling counter nodes doesn't work or doesn't improve the quality?
Else you will have to split your domain.
It can help you: [GAMBIT] 2D ellipse in rectangular domain
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Old   October 14, 2010, 04:17
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ah ok, I understand now.
doubling counter nodes doesn't work or doesn't improve the quality?
Else you will have to split your domain.
It can help you: [GAMBIT] 2D ellipse in rectangular domain
Doubling the nodes only does an increase of the % of cells with high skew.
I read the other post , but the domain in my case is different...
I´m Trying right now with a TRI mesh and it looks better...
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Old   October 14, 2010, 04:20
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sure your domain is different, bt the split technics could help you.
If you are free to work with any kind of element, then I would suggest you to work with quad/pave, and apply a Size Fuction on the smallest ellipse. You also have the possibility to attach a Boundary Layer on it.
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