[Madeleine P. Vincent]

Hi all,

I have a relatively simple solid structure that consists of a 16-sided tube. I want to simulate fluid flow around it. I've created the STL file of the 16-sided structure and a BlockMesh mesh that contains the structure. So far so good.

Now I'd like to add layers to capture finer structures and resolve the BL correctly. I added an "addLayers" section to my SnappyHexMeshDict. And indeed layers are added. When I zoom in using paraFoam, I can see the additional layers.

However, what I see makes me question whether they are actual hexahedra that are getting added. When I view "Surface With Edges", the surface of the pole shows rectangles, which I would expect for hexahedra. But when I add a slice to view, it appears that they may not be hex's, rather that they are 6-sided triangular (or wedge) prisms.

When I view the structure clipped, however, they all appear to be hexahedra, since square shapes show up both on the surface of the structure and along the clip plane. And this is the same for a clip normal to the X and Y directions.

So, according to clipping, it looks like the hex's are being added as expected. I suspect, therefore, that it is just a difficulty for paraFoam to display the hex's properly on slices.

Can anyone confirm this?

And, I suppose to add weight to the argument that they are indeed hex's, the addLayers algorithm wouldn't add non-hex's right? I.e., if layers are being added, then they are hex's.

Thanks for your help,
Madeleine.

[Zaphod'sSecondHead]

Originally Posted by Madeleine P. Vincent

But when I add a slice to view, it appears that they may not be hex's, rather that they are 6-sided triangular (or wedge) prisms.

When I view the structure clipped, however, they all appear to be hexahedra, since square shapes show up both on the surface of the structure and along the clip plane. And this is the same for a clip normal to the X and Y directions.

So, according to clipping, it looks like the hex's are being added as expected. I suspect, therefore, that it is just a difficulty for paraFoam to display the hex's properly on slices.

Indeed, this is a rendering option in ParaView, which you can disable by unchecking the "Decompose Polyhedra" checkbox. This checkbox can be found in the "Properties" panel of your case.