[Tobi]

Dear FOAM'er,

I am creating a series of screencasts where I demonstrate how to build your own case for an arbitrary geometry. The screencasts are split into different topics in order to allow everybody to check out the part he/she is interested in. In general I am talking about the following stuff:

• Geometry preparation
• Geometry reparation
• Generation of patches
• Triangulation of the surfaces (patches)
• STL`s and region STL`s
• Background mesh
• Set-up of the snappyHexMeshDict
• Surface feature snapping and generation
• Layer generation
• Boundary conditions
• Solver settings
• And other related stuff

You can find everything here » Move me to the screencast «

Everything is based on geometry that is shown below and we are using OpenFOAM, Salome and Blender during the screencasts.

Share it, comment it, like it, criticize it, enjoy it,...


Screencast.jpg

[JR22]

Thank you very much for this contribution. I enjoyed the screencast.

[enginpower]

Dear Tobi,
very helpful video tutorials, what you linked.

Thanks so much.

What a pity not got before!

[Tobi]

Originally Posted by JR22

Thank you very much for this contribution. I enjoyed the screencast.

Dear Jose thanks for your reputation points! I may ask Bruno if it is worth to pin that thread. Otherwise it will be lost soon :P
Of course, thanks to you Valentine too, for giving me some feedback.

[sitajeje]

Dear Tobias,

Thank you very much first of all for your teaching on your website http://www.holzmann-cfd.de! I watched through your teaching videos and learned a lot, especially about creating mesh with Salome and snappyHexMesh. Your website is very helpful for beginners like me!

I met a problem with salome. I want to simulate blood flow in a blood vessel, which is basically like a pipe, but has irregularly curved surfaces and flow path. The geometry is saved in .step or a .stl file. I could import the .step file into salome. After I right clicked and chose create group, the dialog box became frozen. I could move the dialog box, but couldn't choose faces. The memory is sufficient, still plenty are free.

I tried a much simpler geometry, a pipe, there was no problem to create groups. Since I began to use salome yesterday, I am not sure whether is it an installation problem or do I meet the limit of salome so quickly in a day?

It would be a great favor of me if you would like to give me some hints! Thank you very much in advance!

All the best,

Sitajeje

[Tobi]

Dear Sitajeje,

thank you very much for your feedback. Salome can be very slow if your STEP is very complex and has a lot of shells/faces/etc. I suggest, wait open it, great groups and then have a break. Sometimes I focus this problem too. Mostly if I extrude a face into a wrong direction (in that case I have to kill Salome) ... However, what you could to is -> extract your shell -> try to build a new solid and then try to create groups (or even with the shell).

Sent from my HTC One mini using CFD Online Forum mobile app

[sitajeje]

Dear Tobias,

professionals are professional! Your hint provides exactly the solution: take it easy and have a coffee break! Thank you very much!

Have a nice evening!

sitajeje

[enginpower]

Hi Tobias,
I'm trying to mesh a very complex geometry to apply snappyHexMesh. I deeply studied your tutorial videos and what I cannot apply is to set the same wire segmentation on both two connected faces. The problem I encountered is that sometimes an edge on one face is different on the other face. In this case, setting an equal 'nb of segments' submesh on both two faces, obviously it misses to connect all points of the border mesh.
I tried to fuse edges, but I've not understood how to manage Fuses, because in that case they are not children of the same face.
So, how to solve that?
Thanks

[student666]

Hi Tobias,

I'm trying to mesh a multiRegion domain with SHM.
I've got 3 domains.
If you have a look at the picture, you may see that internally there is a cylindrical surface I would like to snap better.
That surface is internal and I want only to mesh better the interface between regions.
I tried different ways, even increasing levels on refienements surfaces, but I got a "stepped" surface; I'd like to have it smoothed.

this is an extract of my SHM dict

refinementSurfaces
    {
        fluid
        {
            level (1 1);
            regions
         {
        airAmbOutlet      { level (1 1); patchInfo { type patch; }}
            airAmbInlet      { level (1 1); patchInfo { type patch; }}
            airCombInlet     { level (1 1); patchInfo { type patch; }}
            airCombOutlet      { level (1 1); patchInfo { type patch; }}
            simmetry          { level (1 1); patchInfo { type patch; }}
            wallAirAmb      { level (1 1); patchInfo { type wall; }}
            wallAirComb     { level (1 1); patchInfo { type wall; }}
            wallSolido      { level (1 1); patchInfo { type wall; }}
            }

        }
        tuboScamb1
        {
            level (3 3);
            faceType internal;
        }
    tuboScamb2
        {
            level (3 3);
            faceType internal;

        }
    tuboPlt
        {
            level (3 3);
            faceType internal;
        }

        regionAirAmb
        {
            level (2 2);

            faceZone    regionAirAmb;
            cellZone    regionAirAmb;
            cellZoneInside inside;
            boundary    internal;
        }

    regionAirComb
        {
            level (2 2);

            faceZone    faceAirCombZone;
            cellZone    cellAirCombZone;
            cellZoneInside inside;
            boundary    internal;
        }

How do you set snappyHexMesh dict to snap properly that surface without obtaining extra patches or extra cellZones after using

splitMeshRegions -cellZones -ovrwrite

? Is there a way?

Enclosed there's the step file of the domain.
Thanks for any help.
Regards
Michele.

[student666]

Hi,

solved by setting the following dict:

tuboPlt.stl
        {
            level (3 4);
            faceZone    tuboPlt;
           
        }

when you use splitMeshRegions -cellZones, you don't have any other cellZones.