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[ICEM] Weighted Mesh / Gradually Coarsening Mesh

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Old   June 15, 2010, 22:42
Default Weighted Mesh / Gradually Coarsening Mesh
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Pawan Kumar
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This is really annoying me. I am used to Gambit for a few years and now trying out ICEMCFD. Am I missing something trivial? It was really easy in Gambit.

Here's a simple example and I don't know how to do this: I have a plain 2D surface, lets say a rectangle and I want the surface mesh to be more dense by the "inlet" and less dense as it gets to "outlet". That's it, simple one-way gradient. I want to be able to somehow manage that density and how much I want to distribute the mesh. So the edge nodes would look something like this I suppose:


ooo-o-o-o-o--o--o---o---o-----o-----o---------o----------o---------------o
ooo-o-o-o-o--o--o---o---o-----o-----o---------o----------o---------------o
ooo-o-o-o-o--o--o---o---o-----o-----o---------o----------o---------------o
ooo-o-o-o-o--o--o---o---o-----o-----o---------o----------o---------------o


Any help would be greatly appreciated.

Last edited by pawan1989; June 15, 2010 at 22:58.
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Old   June 16, 2010, 11:12
Default Lots of Power for Edge distribution control...
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Simon Pereira
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Are you using ICEM CFD Hexa blocking? Go to Premesh Params => Edge Params... You will find excellent control with a variety of Meshing Laws, Spacing 1, spacing2, ratios, max space, etc.
Pawan_01.jpg


If this isn't enough, you can choose the Mesh law => From Graphs. This lets you create your own distribution using a graph. Just click and drag to add points. There are also functions you could start with and you could use linear or splines between your control points. This example is somewhat silly, but I wanted to show the idea... The graph in the top half controls the bunching distribution...
Pawan_02.jpg

There is also a Mesh law => Onscreen that lets you maniputlate the distribution directly on the edge...

Once you have the distribution you want, you can copy it to parallel or visible, etc. There really is a lot of power there.
Pawan_03.jpg

Do display your bunching, right click on "edges" in the model tree and display the "bunching". The sice with the base of the arrow is side 1, the other side is side 2.

If you are paving your mesh, then you can find similar (but less flexible) functionality under the Mesh (tab) => Curve Mesh Setup. Scroll down to advanced bunching. To see the curve distribution, you can right click on curves in the model tree to display "curve node spacing"
Pawan_04.jpg
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Old   June 16, 2010, 11:13
Default Try some tutorials
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Simon Pereira
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And yes, this should be covered by most of the Hexa tutorials. Try out a few since there are lots of other key bits of info that will help you out also.

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Old   June 16, 2010, 13:18
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Thanks! I shall be sure to try them out and let you know how it goes. I appreciate your time and effort.
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Old   February 8, 2012, 11:33
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I have gone through the hexa tutorials but I haven't found one which discusses how the gradients become denser approaching both ends of a mesh. Can anyone suggest which mesh law would be best to implement?


ooo-o-o-o-o--o--o---o---o-----o-----o---------o--------o-----o---o--o-o-ooo
ooo-o-o-o-o--o--o---o---o-----o-----o---------o--------o-----o---o--o-o-ooo
ooo-o-o-o-o--o--o---o---o-----o-----o---------o--------o-----o---o--o-o-ooo
ooo-o-o-o-o--o--o---o---o-----o-----o---------o--------o-----o---o--o-o-ooo


Sorry for hijacking the thread, but I thought this is very relevant. Thanks!
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Old   February 8, 2012, 21:30
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Bi-geometric or bi-exponential... Or chose the graphs option and create your own meshing law...
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