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JB January 19, 2005 11:56

GAMBIT Parametric Modelling
Hi folks!

I learned how to use Gambit a couple of month ago and so far I had no problems using the GUI....BUT: I'm currently working on parametric modeling/meshing in a journal file, and I have some troubles: 1.I cannot find any intuitive functions to easily select a set of , let's say edges, by specifying spacial restrictions, for exemple (this was possible and terribly efficient in ANSYS!). 2.I cannot figure out how to use the MINEDGE function (error 500, syntax error , blablabla...). This is a real problem!

Any suggestions?

I appreciate your help!


Chris Bailey January 19, 2005 12:27

Re: GAMBIT Parametric Modelling
Regarding your first problem, I don't think there are functions to select edges - at least I never saw any. I deal with this by always explicitly naming the vertices, edges, faces, volumes, and so forth, in the journal file. For example:

vertex create "LowerLeft" coordinates 0 0 0 vertex create "LowerRight" coordinates 1 0 0 edge create "Bottom" straight "LowerLeft" "LowerRight"

If you do this you always have names to grab onto later.

JB January 19, 2005 12:52

Re: GAMBIT Parametric Modelling
I see what you mean, but in my case, I'm importing a huge 3D model from Catia V4, so it's not possible for me to re-name all the elements. Anyway, thank you for your help, I appreciate.

zxaar January 19, 2005 20:52

Re: GAMBIT Parametric Modelling
you can use journals to do lot of work for your case, and yes as you mentioned , if the model has lot of edges faces and volumes , tracing them is a problem, specially when you can not name each and every face you generate. But then the question is how gambit does that. gambit uses some fixed rules to generate the names for the volumes and edges and faces, so if i were to write a journal for a complicated case, i would rather wirte a c-program that does the name generation for me, or rather finally generate a journal that i could run on gambit to get my model done. it shall not be easy, but i guess thats the way to make it more easy and reusable.

JB January 20, 2005 04:53

Re: GAMBIT Parametric Modelling
Thank you zxaar, that's a good point. My only fear with your solution is the following : the 3D Catia V5 model that I'm importing is still a beta version : event if the global shape of the model should remain the same, the CAD designer might change its way to create the geometry... (he created a parametric geometry of the structure, and our boss want his catia V5 file to be soon useable for more complicated models). But this is a good idea : I'll keep it in mind until this Catia file is the final version!

thanx a lot!

Chris Bailey January 26, 2005 17:58

Re: GAMBIT Parametric Modelling
You can use the loc2ent function. Specify $entityname=loc2ent(t_ed,x,y,z) where x,y,z are coordinates of a point that lies on your edge, and variable $entityname now contains the name of the edge. Use t_fa or t_vo to indicate a face or a volume instead.

Does this get it?

JB January 27, 2005 05:18

Re: GAMBIT Parametric Modelling
thank you Chris, that's finally the way I choosed to solve my journal file is running now ;) but still : i wonder why this stupid 'minedge' function doesn't work!

bye jb

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