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Layer addition problem near symmetry planes

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Old   August 16, 2011, 10:25
Default Layer addition problem near symmetry planes
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Alex
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It seems the more layer addition iterations I specify, the more it eats away at the boundary layer...

Please see attached pics and snappyHexMeshDict file.

Thanks.
Attached Images
File Type: jpg ahmedBody_Slice_X522.jpg (41.5 KB, 126 views)
File Type: jpg ahmedBody_Slice_X522_Zoom.jpg (46.4 KB, 105 views)
File Type: jpg ahmedBody_Slice_X522_Zoom2.jpg (46.3 KB, 104 views)
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File Type: txt snappyHexMeshDict.txt (11.3 KB, 33 views)
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Old   August 16, 2011, 10:49
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Again, I answer my own questions...

I changed:

addLayersControls
{
nGrow 0; //(previously was 1)
}

So nGrow seemed to have been forcing the boundary layer further and further away at each iteration.

I still have the problem of a crease along the symmetry plane. See attached picture. From the forum, I gather this is a common problem...
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File Type: jpg ahmedBody_Slice_X522_almostfixed.jpg (26.2 KB, 79 views)
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Old   December 1, 2011, 06:26
Default Solution?
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Hey bigbang,
I have the same problem did you find a solution?

Regards,
Friederike
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Old   December 1, 2011, 07:04
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Sorry Friederike, I never solved this one.

The solution is to buy more hardware and solve the whole field

But there may be some promise if you look into the new edge handling feature in openfoam 2.x (part of snappyHexMesh).
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Old   December 3, 2011, 13:47
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Hi there,

Try changing your "symmetry" boundary to "empty" in order to get the BL all the way. This workaround does work sometimes but make sure it doesn't messes up the BL somewhere else.

Regards,

B.
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Old   December 5, 2011, 11:06
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Quote:
Originally Posted by bouclette View Post
Hi there,

Try changing your "symmetry" boundary to "empty" in order to get the BL all the way. This workaround does work sometimes but make sure it doesn't messes up the BL somewhere else.

Regards,

B.
In my experience this doesn't work, but I have seen this solution before on the forum. Good luck.
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Old   December 8, 2011, 07:35
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Hey,
thanks for the answers. I changed the symmetry boundary condition to empty and it worked so far, that close to the boundary the layer looked good. Unfortunately the boundary layer does not strech around the whole geometry. It starts and stops and I don't know why. I attached picutures ...
Any experience with that, anyone?
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File Type: jpg ok_layerCloseToBoundary.jpg (69.6 KB, 71 views)
File Type: jpg stoppingLayer.jpg (39.2 KB, 73 views)
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