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Volume mesh - crashing - Netgen: Geosearch

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Old   August 19, 2014, 15:30
Exclamation Volume mesh - crashing - Netgen: Geosearch
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Gowain
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Hi
can someone explain the netgen geosearch error-i have been having trouble with this for a number of days now: I have simplified my geometry aswell as improved the mesh in an effort to resolve this - indeed, I can create a prismatic layer prior to surface meshing but not after - and I can not surface mesh after I have a prismatic layer, so perplexed.
See geometry below for idea of case;
any info on such errors would be great - indeed it would be a help if such error messages were more informative -
hopefully get it later - does engrid core dump on low slower machines ?
kindrgds
g
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Last edited by eaglemckenna; August 19, 2014 at 17:12.
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Old   August 19, 2014, 17:32
Lightbulb :)
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Think i have it now - must have been something to do with my terrible meshing up near inlet and outlet points in the domain ^ haha
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Old   August 20, 2014, 12:44
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M. C.
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Hi,
I'm very interested in engrid, but one thing stops me is something I red somewhere, sorry I don't remember... anyway it was said that you have to define for all faces, a patch_name, or during meshing the sharped edges will be smoothed if same patch holds two connected faces. is it true? is there a workaround?
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Old   August 21, 2014, 10:59
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Hi
I created my model and assigned the patches within blender prior to exporting into engrid - engid surface and volume mesing does not smooth out sharp edges between patches, i.e "front" and "left1" or "top2" and "right".
Overall I would say engrid is a great tool and most problems can be worked around when modelling with blender.
kind rgds
g
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Old   August 29, 2014, 03:57
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Hi,

I'm trying to setup a test case ( a cube ) to learn how to use engrid, I generated the stl file into Salome, then I Imported the STL file into blender.

I installed the add ons as for the following thread Blender Export to Engrid script for Blender 2.69?

I exported the file for engrid, but I get this message:

Code:
 p, li { white-space: pre-wrap; }  smallest edge length is 1e+99
 secs. for IOOperation: 2
 deleting Operation 0x24f61c0
can you help me with this?

thanks a lot

PS: I'm using blender 2.71

Last edited by student666; August 29, 2014 at 05:34.
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Old   August 29, 2014, 10:38
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Mmmm
You should just work inside blender and make a cube:
1 - make sure cube is sized correctly 2mx2mx2m is default and is ok.
2 - make sure cube is water tight
3 - make sure normals point away from fluid (edit mode press w for menu)
3 - assign patches inside blender (edit mode face selection P assign selection)
4 - select all of the cube and patches inside edit mode and export into engrid .begc file
5 - open with engrid and strike C to check mesh

rgds
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Old   August 29, 2014, 19:52
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Hi G,

if I start from blender and follow the instruction:

https://github.com/enGits/engrid/wik...ting_the_Model

by working with blender all goes to an happy ending. But my request for help comes from complex geometry.

Now I would like to test engrid in order to verify if it is easier to add layers as with SnappyHexMesh is quite hard.
Normally I model the CAD geometry and export the .stp file to Salome, then I generate single stp file according to my patches, then in gmsh I import and mesh once again for a good quality of the stl and export to OF as stl.


I thought it was possible to follow same workflow, and to import stl files in blender (after gmsh) and export into Engrid for meshing. But even for the simplest case (the cube) I get the error above.

any other suggestion?
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