Help GAMBIT IGES import problems

[123qwe456]

I am trying to run a CFD of a pip with a lot of internal plates. I created geometry into Pro/E and tried to bring it into Gambit as an iges file. According to my professor I have to brake the inside volume into a number of volumes with different flow parameters. If I import iges as solid I have only one volume. If I import geometry as iges-surfaces I have a lot of disconnected surfaces and more than expected number of edges and vertexes. For example for a vertex shared by three surfaces gambit creates three vertexes with the same coordinates – one for each surface. Is there any way to avoid this without actually manual creation of the geometry in the Gambit?

 

[poetix99]

Try posting your question in the "Finite Element Analysis engineering" forum; although is concerns CFD, I think that there is a generic CAD/FEA issue at its bottom.

 

[HamishMcTavish]

Isn't there any way that you could exploit rotational symmetry to reduce the geometry to a more simple configuration?

 

[123qwe456]

Thank you for your comments.
I would like to add that the problem is not symmetrical. Currently I have finally found the way to import STEP files. However I still have the software recognize it as one volume. Now everything comes to finding out how to create two volumes that would share one surface. I tried to create two cubes in a different CAD software (SolidWorks, CATIA, Pro/E even AutoCAD solids) using different techniques (inserting a flat surface, assembling two cubes, merging surfaces) however I have not had any luck to obtain a two-volume geometry with one surface shared in GAMBIT. Has anyone dealt with the same problem? Is there any way around it in GAMBIT?
Thank you.

 

[waterguy]

I've had some limited experience with GAMBIT and FLUENT, but regarding the multiple vertices at the same location, I believe that GAMBIT has some sort of "tolerance" command that will allow you to consolidate those multiple vertices into one.

Regarding the volumes/surfaces problem...I don't know. I remember having to manually create edges and faces using GAMBIT's tools once the geometry was imported.

I'm assuming you have access to manuals, but if not, the link below has all the documentation for GAMBIT and FLUENT.

http://sp81.msi.umn.edu.:999/fluent/

 

[MJSTOKES]

Hi,

I've been using gambit for a short while now but have learnt some usefull things.

If you export the Pro-E geometry as a step file and import it in to gambit this should/will remove most if not all of the problems found with the iges file.

After that how you wish to decompose the geometry is up to you!

Good luck

 

[MJSTOKES]

To connect your geometry you can do a number of things.

1st method...

Go to the Vertex menu and click on the connect button
Connect all vertices

Then

Go to the Edge menu and click on the connect button
Connect all edges

Then

Go to the Face menu and click on the connect button
Connect all Faces

This will connect the various objects where this is possible.

If this doesn't work then you can perform a bi-directional split command in the volume menu and providing the components are within the default tolerances the geometry should then be connected - you may end up with additional volumes depending on you original geometry.

Hope this helps