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Nils_H July 31, 2012 10:53

Meshing of fluid and solid zone of complex structure through OCTREE
Hi there, I have a short question about the meshing procedure of a complex structure, I hope you can help me out with a short hint....

1. Import Geometry --> from stl
2. Octree meshing (I now have the surface and volume mesh of the complex 3D body, closed shell, everything perfect so far)

For the flow simulations I need the inverse volume, the fluid zone, which can be declared by material points), what I read so far.

3. Geometry --> create body

4. Now what to do, to export the mesh containing the solid and fluid region to Fluent, and how to generate the fluid zoneīs mesh? Iīm really stuck at this point.

Thanks in advance! Best regards, Nils

Nils_H August 1, 2012 05:29

Additional info
The solid of the structure is meshed through octree out of the stl file. Inside the sintered structure, I place a gemoetry (block) to have only a representative volume of the invert solid = the fluid. How do I combine both of the structures? And why is Octree of a simple block giving me several error when meshing with Octree? What is wrong? Please guys, I really need some help on this one. Thanks!

lostinicem August 1, 2012 05:42

so you have two different mesh types?
the octree should be defined with body-option; the block part with solid. this will guarantee that fluent will get 2 zones. in fluent in option "cell zone conditions" you define which is fluid and which is solid. for example if your block part should be fluid, you just change the options in fluent: click on solid and change to fluid ...
but with a picture it would be easier to understand your problem :)

Nils_H August 8, 2012 10:38

The only way to mesh these complex structures is the Octree meshing apporach. Is it possible to create a solid body out of the volume mesh? I mean, the created shell is closed and can be transferred into facets, right? Can this closed surface be used to create a solid body? Thank! I will also post some picture of the same problem (see above). Best, Nils

Nils_H August 17, 2012 07:30

Meshing still doesnīt work :/
3 Attachment(s)
Hi there, in order to have a 3D mesh of the pore volume of sintered structures I need some help. The structure import is done as geometry (stl). The stl surface mesh (shell) is water tight, octree works as well as Delaunay. The issues Iīm having is regarding the representation of the inverse volume (not solid, but fluid pore volume inside the structure). Regarding the pics, I place a volume inside the solid structure (blue block) and the intersection between this volume and the shell should divide the mesh into 2 seprate mesh zone, which can be declared later in Fluent as fluid and solid zone. The wall boundary conditions of the volume are later set as inlet, outlet etc. That is the plan so far.

Anyway, whenever I let ICEM mesh the fluid volume and the solid region, the meshes donīt see each other. The solid mesh from the CT scan stays the same, but the fluid zone is just one block of 3D mesh without having the inverse volume of the solid sintered structure. I choose the option "mesh internal domains" as well as I declared the shell of the stl structure as "internal wall". Any suggestions but be very very helpful! What am I doing wrong? Thanks in advance.

The summary of the above: How do I gain the fluid zone mesh out the stl data for an import to Fluent?

Nils_H August 21, 2012 03:46

Anyone? Some hints, suggestions...?

yonchong August 21, 2012 14:26

Is it possible to post the STL solid model?

yonchong August 21, 2012 14:36

Build Topology
Did you also try Geometry->Repair Geometry->Build Topology to split surfaces where necessay and merge surfaces where overlap?

Did you also create body using Geometry->Create Body?

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