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[ICEM] Octree surface mesh issue

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Old   January 23, 2011, 04:18
Default [ICEM] Octree surface mesh issue
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siw
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I've made three meshes around an aircraft: coarse, medium and fine with the Octree method in the usual manner (What's the correct unstructured mesh procedure).

The surface meshes on the nose and tailplane are shown in the images: coarse on the left, medium mesh on the upper right and fine mesh on the lower right in each image.

I set the octree sizings on the medium mesh using: 1/8, 1/4, 1/2, 1, 2, 4 etc and used a global scale factor of 1.5 for the medium mesh and 2 for the coarse mesh.

The coarse mesh looks okay but why does the medium mesh show regions which are too coarse (see nose apex and fuselage at the tailplane mid-chord)? The scale factor should not allow this too happen.

Thanks
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File Type: jpg Nose.jpg (62.2 KB, 41 views)
File Type: jpg Tailplane.jpg (58.0 KB, 42 views)
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Old   January 30, 2011, 16:27
Default Looks right to me...
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I am just looking at still images, without the ability to measure, etc. What makes you think there is a problem?

Have you checked the edge lengths (there is a quality metric for that or you could just measure a few manually to compare). I did that roughly by eye and it looks about right to me.
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Old   January 31, 2011, 02:46
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Hi,

I could not see any metric for edge length so I measured a few elements on the nose and on the fuselage on in the mid-chord region of the tailplane and they are bigger on the medium mesh(!)

I've marked the images where the larger elements are occuring on the medium mesh to highlight where ICEM looks to be getting it wrong.

Thanks
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File Type: jpg Picture2.jpg (53.8 KB, 32 views)
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Old   February 4, 2011, 04:25
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Does anyone else think there's no problems with my intermediate mesh?
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Old   February 4, 2011, 07:27
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Could you post others pictures with your geometry only ?
I would like to see your curves.

You could also check the number of nodes that ICEM puts on your curves for all your models.
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Old   February 4, 2011, 08:49
Default I see it, I just don't understand it...
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Hey SIW, I see it now at the nose, I just have no idea why it would do that. I will think about it.

Simon
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Old   February 13, 2011, 12:46
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Simon, any thoughts?
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