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kate February 19, 2000 03:07

volume generation
 
Hi,

I'm experiencing some problems in volume generation. I have this neu.gz file which I import to gambit and it's a 2D mesh. I'm trying to construct a cylinder using the sweep real faces command by the means of a rigid sweep and specifying a vector. But I get a error msg that says "cannot perform function on xxxxxx-face with associated non-real geomety". What is the problem???

Regards, Kate

Kai Kang February 19, 2000 11:21

Re: volume generation
 
there must be some virtual geometry in your model, if you check either your volume or face or edge, you will find some are lable like v_edge.xx, v_face.xx.

Frank February 19, 2000 11:25

Re: volume generation
 
If you import a mesh into gambit, it becomes virtual (!!) geometry. Virtual says, that you do not have the full functionality of gambit for further operations, such as sweeping, uniting... 1.) Try "sweep edge" or "rotate edge". I think, this works with virtual geometry. After rotating or sweeping build a volume. 2.) try "convert virtual-real" in "faces". If this works you can try to sweep the real face

Frank

Pavel Strasak February 22, 2000 12:38

Re: volume generation
 
The second way is the export of acis file and re-read it in new task. This step deletes the virtual entities.

Best Regards

Frank February 22, 2000 15:30

Re: volume generation
 
But this often does not work: if you read the (exported) sat-file, GAMBIT hangs up.

Pavel Strasak February 23, 2000 04:19

Re: volume generation
 
Of course, because the basic geometry is damaged. 1) Then it is problem with iges translation. Sometimes you can get some information on shade model, because distorted faces are in wireframe model, not shade. 2) Those faces are not converted in real geometry. Then you must convert the edges and recreate new real face. 3) When the face is very curved the best way is to split it and then convert the edges in real.

Pa.St.

Kate February 24, 2000 02:36

Re: volume generation
 
Frank,

I've tried the methods that u've suggested but they still dun work. Would u like a copy of my grid file? pls email me ASAP. Thanx a million.

Frank February 24, 2000 15:48

Re: volume generation
 
Yust before one question: why so complicated ? a meshed cylinder is made in gambit in 5 minutes. Frank

kate February 24, 2000 21:51

volume generation
 
Frank,

That's why I think you've gotta see the mesh. It's a flat 2d almost circular mesh with 3 zones. As I've asked you earlier, would you like to have a copy of it? I've been told to reconstruct 3d volume by inputing the grid coordinates all over again, but that's really ridiculous and I think gambit def has the funtions to do it. It's just that I dun knoe how. Thanx.

Frank February 25, 2000 17:25

Re: volume generation
 
ok, I'll try it.


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