Elmer Discussion Forum

Hoepfully this image will come thru. This is a ElmerPost image of a cylinder meshed with 10-node tets prepared by Netgen. As you can see, some of the element faces are transparent and some are opaque. I am wondering if this is a graphics issue, or if it has something to do with the mid-side nodes.

Thanks,

Yes, that seems suspicious. Could you elaborate on the route that the mesh took after being defined in netgen, or did you use the netgen plug-in of ElmerGUI? In either cases attaching the problematic file might help.

-Peter

Thanks for your response.

The mesh was exported from Netgen in Elmer format. I believe I tried the standard .vol output first, but Elmer would not accept it.

Attached are the mesh files output by Netgen, the computer Gods willing.

Thanks again.

By the way, this beautiful effect does not appear in the preprocessor view in Elmer, only in post.

Answering my own question:

This is what you get when you are new to Elmer and try to solve a structural problem with 2nd order elements with a linear solver. Changing "Equation = Linear elasticity" to "Equation = Nonlinear elasticity" fixed it nicely.

2nd order elements should work for the linear problem as well. I think that there may be a discrepancy between the local node numbering of netgen and elmer. Probably the effect does not appear in ElmerGUI because only the corner nodes are used to vizualize the geometry. The change should rather be made on the netgen side.

-Peter