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Old   June 1, 2021, 09:27
Default cfMesh noisy mesh
  #1
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Ingo
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Hello

I tested a bit with cfmesh and therefore i created a simple cube in blender, parts of it were exported seperately so i got a merged stl which i turned via surfaceFeaturedEdges -angle 15... into a .fms file.

Now i had a few boundary layers on one side with additional refinement layers and my mesh is kind of very noisy. It even was before the refinement process.
Please have a look at the Dropbox Link for picture.

My meshing settings were really simple and i tried to avoid the automatic refinement process by putting in the minCellSize equal to maxCellSize:

Code:
surfaceFile "test.fms";

minCellSize 0.15;
maxCellSize 0.15;

localRefinement
{
links
{

additionalRefinementLevels  5;
refinementThickness 0.002;
}
}

boundaryLayers
{
	nLayers 2;
	thicknessRatio 1.2;
	maxFirstLayerThickness 0.003;	

patchBoundaryLayers
{
	links
	{
	nLayers 10;
	thicknessRatio 1.2;
	firstLayerThickness 0.0001;
	}
}
I do not know why the mesh is so noisy when putting in such a simple geometry..

Would appreciate any help

Best wishes
Ingo
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Old   June 11, 2021, 06:51
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If thats paraview, its just visuals. Deactivate "decompose hexahedra" and use crinkle on cuts and planes.
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Old   June 11, 2021, 19:49
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Yes that is in paraview.

How can i deactivate it? Even by googling i did not find it..

What is that other thing?
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Old   June 14, 2021, 06:37
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On the .foam-File node in Paraview, below the Point and Cell Data, there should be the switch for decompose polyhedra. If you don't see it, you might need to enable the full settings, by clicking the small "gear" symbol prior to that.
Same for the crincle option, in the properties of a clip or slice look for an option with "crincle".


Sorry I misremembered the naming of the option, its polyhedra not hexahedra.
Attached Images
File Type: png step1.PNG (10.8 KB, 13 views)
File Type: png step2.PNG (2.4 KB, 10 views)

Last edited by AtoHM; June 14, 2021 at 07:44.
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Old   June 14, 2021, 18:43
Default It worked! :)
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Actually that property of Polyhedron did not work for this purpose but the crinkle stuff worked, thank you very much
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