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Hi again

I've tried to create the simplest geometry(sphere.. .dxf file is attached) in maple13 and export it as .dxf

Comsol read this geometry with 1 warning: Non-zero Z coordinates ignored.

The problem is that I've got 2d geometry of sphere in comsol's 3d space..

Did anybody import .dxf 3d images?

Hi

si the parallel discussion with

"importing *.sat file"

3D dxf is not supported (from my knowledge) as this format does not store how to connect the lines and comsol gets lost in 3D (most software will do anyhow).

Cannot you try another 3D interface, and if its simple geoemtry, you could programme MAPLE to generate the simpel 3D comsol geoemtrical commands and then import this as an .m fle via matlab, no?

good luck
Ivar

Hi Ivar, thanks for reply

actually I have the implicit equation of 3d surface ( ''cos(x)*sin(y)+cos(y)*sin(z)+cos(z)*sin(x)=0'' )
but in any case I've tried to create 2d circle in matlab and then open this .m-file as model in COMSOL...
COMSOL gives " 'circle.m' is not a valid COMSOL Multiphysics Model M-file " error.

How can I use geometry that were created in matlab?

thanks,
Alex

Also I've tried to import as FEM but I couln't create a FEM structure in matlab..
I can create m-file only...
how I can do that?

Hi

such a surface must be discretised or simple "meshed" to be read into comosl, I would use the ALE and use it as a target for a surface defomation within COMSOL, then save the meshed geometry.

Ivar

Hi

Sorry, but what is ALE??
Can I do it by something else?

Thanks,
Alex

I have also had difficulty with .dxf import in the CAD importing module of 3.5a The app I have been modeling with supports .stl files and it works pretty good so far other than a few triangulation on import errors or those pesky singularities situations. Good luck on your problem solving. Scott

Hi Ivar,
problem partically solved.

for .dxf import I used solidworks(open .dxf as 3d object) and saved as .x_t

another problem is how to fill my shape with the matter.. COMSOL didn't do that automatically.. and i have just closed surfaces..

my geometry is surface of a cube plus some surface inside it. therefore I have 3 closed surfaces: cube and 2 closed surfaces incide it..

I've tried to import .x_t with "try to make solids" but I succeeded only in getting solid cube with surface within.

Can you give an advice what can I do with this?

Thanks,
Alex

Hi

try to do it in SolidWorks then, the CAD geometry possibilities are larger therein, you can cut your cube volume by the surfaces (if they extend far enough) and then you can export the resulting volume.

If you manage to get the surfaces and cube into COMSOL there are also possibilities, but very complex shapes as your have are probably heavy to handle.

It's worth a try, by decomposing the volume into surfaces and then attemppting to recombine surfaces into a volume, but you must select a closed surface for this to work

Good luck
Ivar