the meshing problem in openfoam
 

Hello foamers ;

I'm trying to learn my self openfoam ,, i see some examples in the tutorials and then i makes some very simple geometries using blockMesh

but now i decide to make my own mesh ,, i found it is not easy to use blockMesh to make complex meshes ,, it is very time consuming

instead i search that forum to find solutions ,, i found some members use a program called netgen to make their meshes ,, i got this software ,, but it need strange input format files like " *.stl , *.stlb , *.step , *.stp , *.geo , *.igs , *.iges , and *.in2d i don't even kow how can i make this files that contain my geometry !! ,, if any one know how it works please help me

also, i wonder why openfoam doesn't accept meshs from ,for example, Autocad that we can make our meshes using it very easy and accurate ,, and save much time !! .



thank you very much

Hi Sayed.

Have a look at Wikipedia here: http://en.wikipedia.org/wiki/List_of..._(alphabetical)

There you can find out, what the "strange" file formats are from. Most of them are simply standardized 3d-CAD formats (not native to special CAD software), to which most 3d-CAD programms can export. AutoCAD, as you mentioned, is a 2d-CAD programm and thus rather outdated (in my opinion). I don't know, wheter there is a support for native Autocad formats or wheter you can export into a standardized file format from AutoCAD.

Cheers
Wolle

thanks , Wolle ,, it is not easy to even make a sphere mesh using blockMesh ,, and i think it is the pitfall of openfoam , perhaps if the openfoam stuff or any volunteers solve this problem ,, the other comercial softwares will die and fore ever :D

do you know any meshing software that is easy to deal with ? for some beginner like me

the problem now is what program should i use to draw my 3-D model which its output file is accepted for netgen ? could any one have any idea

I am sry wrong thread ... :mad:

Fabian

what are you talking about , fabian

Hi sayed,

I used AutoCAD in my workflow too, but I needed AutoDesk Inventor to translate the 2D-data into volumetric ones.
Why you not use SALOME ? I think it's pretty easy to deal with.
( And you got much of help and documentation.)
It's an open-source CAD and meshing tool in a whole.
For translation to OF you could easy use the *.unv Format.
The ideasUnvToFoam utillity is working fine since OF 1.5 (except quadratic meshes).
I never used blockMesh it's to time expensive, instead to assign some algorithms (like Netgen :-) ) and hypothesises in Salome.

just an advise
Regards, Robert

Salome is quite useful
 

Hi,

I agree with Robot, Salome can do a good job using opensource meshing (using netgen/gmsh as one of mesh opportunities). Maybe Engrid in combination with Blender is also an alternative to salome in some cases http://engits.eu/phpBB3/viewtopic.php?f=2&t=62

Tutorial salome and openfoam: http://www.caelinux.org/wiki/index.p...ELinux_2007.29

Part 1, Geometry modelling in Salome : PipeGeom2007 on the web or Download PipeGeom.swf
Part 2, Meshing in Salome : PipeMesh2007 or Download PipeMesh.swf
Part 3, CFD analysis in OpenFOAM : PipeOpenFOAM2007 or Download PipeOpenFOAM.swf

other tutorials on how to model see
http://www.salome-platform.org/user-...alome-tutorial
or
http://www.salome-platform.org/user-section

salome has some installing flaws on debian/ubuntu work around
http://code-saturne.blogspot.com/200...on-ubuntu.html

good luck

elvis