[Julierte]

Hello everybody,

I am quite new to CFD-Simulation.

I am working on a square cavity which has different elements inside.
I had problems for meshing the model due to self-intersections.

I tried to repair the surface mesh but I have no idea how to do that. Of course I already referred myself to the user guide.

I've got 55 pierced faces and I don't really know how to fix them.

I hope you guys can help me out.

Thank you very much !

[fluid23]

Create an automated mesh operation (Geometry > Operations, right-click, new, automated mesh). Next, select the input parts from the geometry shown and select surface remesher AND automatic surface repair. Then configure the automated mesh options to give you the surface mesh you want. Finally, execute the mesh operation. 99% of the time, this will solve most if not all of your issues.

If that doesn't work, then post back here. I will try to give you advice on manual repair.

[Julierte]

Thank you very much for your answer !

Unfortunately, your method doesn't work but I don't know why ...

Here is the geometry I'm working on :


And after executing the automated mesh as you told me to, I have this :


So yeah really different of what I expected ^^

Just to show you, here is what I have when I search for the pierced faces :


Tell me what you think about all that ...

Thx again for your help !

[fluid23]

The second image you show is a volume mesh, not a surface mesh. Are you executing other mesh processes in addition to surface remesher and repair? Only execute the surface mesher and show me that (you should see tet elements in a surface mesh). Also, make sure to give it a small enough target size that you have at least a four or five tet elements through the thickness of your part.

On the third image, it looks like there could be a tolerance issue for merging adjacent faces, but before we address that I want to see just your surface mesh.

[Julierte]

My bad for the second image, indeed I executed a volume mesh ...

Just by executing the surface remesher and automatic surface repair as a surface mesher, I obtain this result :

[fluid23]

Can you click the Show All Meshes button at the top so I can see the actual mesh in addition to the surface itself?

Also, what are the basic dimensions of this part? (length, width, thickness)

[Julierte]

All meshes :


And for the dimensions, here is a quick design drawing of my geometry :

[fluid23]

Image 1 is small, but I can kind of see what I was looking for. Reduce your base, target and minimum sizes in the surface mesh operation. I would maybe cut your base size by half and (assuming you left your default settings for target and min), leave target at 100% and set minimum to maybe 1%.

Image 2 is not available.

[Julierte]

Yes sorry about that ... just fixed the problem for the images

[fluid23]

Ok, so are those baffles on the inside? You will need to select surface mesh sizes that will put at least 3-5 tet cells between the baffles. It looks like you will actually need to include some customer surface controls and split up your surfaces so that you can resolve the small details separately from the large surfaces. So maybe have one control for the baffles on the ends. Another control for (whatever that thing is in the middle). And let the default controls set the larger surfaces.

It is important to note that your volume mesh is created from your surface mesh so it is critical that you resolve the surface details sufficiently before executing your volume mesh.

[Julierte]

It's an empty basin with a central board, which as lateral boards coinciding with the basin.
On the sides of the basin, those are radiators (6 on each side) coinciding with the basin too.

[Julierte]

Ok, so I've done what you said and tried so put some custom controls on specific regions.

It seems to work quite well on the left part of the geometry but not on the right.

[IMG][/IMG]

I continue to improve the controls on these parts to resolve it.

[fluid23]

Ok, now... go into your surface mesh operation. Change default controls > auto repair minimum proximity. I think default is 0.01. Maybe try 0.001 and see what you get.

[broadway-1@daum.net]

Resions-Feature Curves

Make Feature Curves~!

[Julierte]

After several changes, the problems are now located only where 2 bodies are in contact.

I think I have to settle a special control for the surface proximity to fix it.

[IMG][/IMG]

@broadway-1@daum.net What do you mean about the feature curves ?

[Julierte]

It's better than before but I still have problems where the surfaces are touching each other.

[IMG][/IMG]

[IMG][/IMG]

[IMG][/IMG]

I tried several things, but nothing really works ..

Do you have an idea ?

Thank you very much for your help !

Cheers

[fluid23]

I am unable to respond to your private message...

Run your remshed surface (not the orginal geometry) through surface repair and look for pierced faces, take a screenshot and send it to me.

[Julierte]

This is the model in the repair mode AFTER applying the automated mesh ..

[Julierte]

Just noticed that in the output, I've got a message saying "Error during orientation. Surface not oriented! Warning : could not orient the surface. Face proximity may not be accurate." when I run the automated mesh.

[fluid23]

Yeah, I am not too sure about that error. I would suggest submitting a case to your support engineer via the Steve Portal.