CFD Online Discussion Forums

CFD Online Discussion Forums (
-   FLUENT (
-   -   Convert Real edges to Virtual in Gambit (

Freeman October 20, 2005 10:24

Convert Real edges to Virtual in Gambit
Hi all!

I've got a little question using Gambit. I know that there is an option to convert virtual edges into real ones but is there any way to make the inverse step, i mean, to convert real edges into virtual??

Thanxs in advance.

Dan October 20, 2005 11:01

Re: Convert Real edges to Virtual in Gambit
Can i ask why you'd want to? You can create virtual faces/volumes from real edges, so there's no real need to. Whereas there is some merit in converting a virtual edge to a real one.

Kind regards,

Freeman October 20, 2005 16:35

Re: Convert Real edges to Virtual in Gambit
Thanxs Dan for your interest Dan.

Well, I will explain you the whole issue. I have a 2D drawing that I'd successfully imported to Gambit as a .sat file. In order to make a mesh as I want, I create little faces (subfaces) that divides 2D domain: these subfaces are made from virtual edges that I draw first with Gambit's tools.

The fact is that it is much more comfortable for me to draw geometry in AutoCAD and then import it into Gambit than to create geometry with Gambit's tools. It would be nice to draw these subfaces' edges in AutoCAD and then, make them virtual in Gambit (because all geometry imported is real and I need these edges to be virtual, as they are only a way to create and mesh these subfaces, and I don't want them (edges) to appear in Fluent).

I don't know if that above has been as clear as I wanted :S

Is there any tool that makes so?

edi October 21, 2005 04:14

Re: Convert Real edges to Virtual in Gambit
As long as you divide your surface into subfaces with internal edges that are connected (not overlapping), these edges will be set by default as interior by gambit when writing the mesh and they won't appear in Fluent.

Hope this helps


Freeman October 21, 2005 15:35

Re: Convert Real edges to Virtual in Gambit
Thanks edi!

But these internal edges you are talking about are real or virtual? I think I don't understand you when you say "internal edges", what do you mean?

I've tried drawing the edges in autoCAD (with the rest of the geometry), importing it to Gambit, creating and meshing the subfaces with these edges and when I make the mesh file and open it with Fluent, these edges appear... Your method is similar to this?

Thanks a lot!

edi October 24, 2005 05:37

Re: Convert Real edges to Virtual in Gambit
The edges I was talking about are real. By internal edges I mean edges that are not at the boundary, i.e. they are shared between 2 subfaces (I don't know if I make myself clear).

It seems to me that your so called "internal edges" are not connected, so when you read your mesh into fluent they are set as walls.

Check in gambit if these edges are connected, since when you import some models from cad packages they usually aren't.

Hope this can help


Freeman October 24, 2005 15:14

Re: Convert Real edges to Virtual in Gambit
That was the point.

I've just tried to draw all the geometry in AutoCAD, imported it to Gambit and when the mesh was done and imported to Fluent, those edges simply dissapear as you said.

Many thanx eddie, that was very helpfull!

All times are GMT -4. The time now is 01:31.