[Gmsh] How to create single mesh with multiple bodies

[李昊]

Dear Prof. Geuzaine,

Thanks so much for your reply! I tried to use "fragment". And it does work,
now the results look reasonable:
[image: image.png]

The multiple bodies have remained as well:
[image: image.png]

Thanks very much!

Best regards,
Hao
-------------------------------
Kyoto University
Department of Mechanical Engineering

Christophe Geuzaine <cgeuzaine at uliege.be> 于2019年11月12日周二 下午9:39写道：

>
>
> > On 12 Nov 2019, at 13:14, 李昊 <lihao71862b at gmail.com> wrote:
> >
> > Dear all,
> >
> > I use Solidworks to sketch a 3D part as shown below. In this model,
> there are 9 volumes.
> > <image.png>
> > Then I export ".step" and import into the gmsh.
> >
> > Then I use Gmsh to generate 3D mesh as below:
> > <image.png>
> > Till now, everything looks good.
> >
> > After that, I export ".mesh" to FreeFem for numerical simulation. Now
> something strange happens:
> > I apply a force on the left side wall, and make the right side wall to
> be fixed.
> > However, both rings does not have any displacement. That means the rings
> do not take part in the computation.
> > <image.png>
> >
> > Next, I used Boolean operation in Gmsh to merge all the nine volumes to
> be a single volume
> > <image.png>
> > This time, the result seems reasonable:
> > <image.png>
> >
> >
> > Please note that we hope to maintain the multiple bodies rather than a
> single body. Because we need to apply different physical properties for
> each domain.
> > Therefore, is there any way to create a single mesh with multiple bodies?
> >
>
> Yes, use BooleanFragments instead of BooleanUnion: it will preserve the
> internal boundaries.
>
> Christophe
>
>
>
> > The CAD model "auto_part_2.STEP" is attached.
> > Both meshes are uploaded as well. The multiple volume one is named as
> "auto_part_2.mesh". The single volume one is names as "auto_part_2_1.mesh".
> >
> > Please kindly check them.
> >
> > Thanks very much!
> >
> >
> > Best regards,
> > Hao
> >
> >
> <auto_part_2.STEP><auto_part_2_1.mesh><auto_part_2.mesh>_______________________________________________
> > gmsh mailing list
> > gmsh at onelab.info
> > http://onelab.info/mailman/listinfo/gmsh
>
> —
> Prof. Christophe Geuzaine
> University of Liege, Electrical Engineering and Computer Science
> http://www.montefiore.ulg.ac.be/~geuzaine
>
>
>
>
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