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srceko25 June 4, 2010 11:46

Import terrain model from CAD?

I am quite new to ANSYS/FLUENT and I would like to know how can I import a terrain model from AutoCAD to ANSYS geometry? The AutoCAD .dwg file contains height contours of the site and is in a local coordinate system. Do I need to manipulate the original file in some way for it to be usable for ANSYS? When I just upload the file that I have I get the error (invalid geometry).

Thank you for your help!!

srceko25 June 11, 2010 02:43


Edu-R June 11, 2010 09:11


Have you tried to export as IGES or STEP file? Ansys could read it, but I donīt know if AutoCAD can do it :S


zeitoun June 14, 2010 07:18

I'm also in the same case.
There must (I guess !) be a way to just import points from the CAD file into Ansys Design modeler.
Those point should appear simply as construction points that can then be used to construct the geometry inside Design Modeler, and NOT do the whole geometry in the CAD software and export the finished solid geometry, which is more difficult..

Does anybody here around know how to export points from a DWG Autocad file into Ansys DM ?

cheers, Z

kdrbrk June 16, 2010 02:50

Is your terrain a 3D surface in autocad?

zeitoun June 16, 2010 16:06


Originally Posted by kdrbrk (Post 263175)
Is your terrain a 3D surface in autocad?

No, it's just points. No line or surface or solid. Just points.
I have to build the solids in another tools. Why not Ansys Design modeler ?


Will C June 22, 2010 16:09

I've been working on almost exactly the same problem.

Unfortunately, I don't think you will find AutoCAD or Design Modeler to be much help in your particular case.

Look at other software programs to help you in this endeavor. Take a look at the programs by Sycode. You can download them for free for a limited number of trials:

We've been using a program called Vulcan to render our geometries, but it is pretty specialized and very expensive.

I've also heard that you can write a Matlab code to render your geometry, but this sounds extremely onerous.

Good luck!

sac June 25, 2010 04:38

It can be done in DM.

I take it you want to do it through sketches.

If so just start a new session of DM -> go to the sketching menu and make a few random points -> then go back to the modelling menu on the tree and pick the sketch -> then go to the file menu on the bar and then "write script: sketches of active plane". It should produce you a javascript file that shows you what you've done in that sketching session. You can then edit the javascript to match the points want to add.

There is a good example of what to next with these points in the DM manual -> Scripting API -> Features example.

Also the point feature in the create menu can import co-ordinates files.

zeitoun June 26, 2010 05:36

what you said is interesting.
I've been trying this way. The only problem is the point feature in DM needs coordinate file with a certain format, and that is not a .dwg file.
So now the point is: how can I convert a set of points in autocad to a list of coordinates into a file ?
Any idea ?

sac June 28, 2010 04:51


Originally Posted by zeitoun (Post 264610)
So now the point is: how can I convert a set of points in autocad to a list of coordinates into a file ?

I'm sorry I don't use autocad so I cannot tell you how you would get that information out of it.

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