[Gmsh] Errors when increasing NNodesByEdge on a small edge

[Nathan RICKS]

Hi all,

I have quite a particular problem, but I'm hoping someone can help. I'm meshing an airfoil using transfinite surfaces in the boundary layer.

I've just had to add a blunt trailing edge (mesh was working well with sharp trailing edge) to the airfoil, and now I have this one error stopping me, and I just can't figure it out...

When I increase the NNodesByEdge on Field[11] from 6 to 15, the mesh ends up bad quality, with cell corners not matching other cells at the boundary of surfaces, and it causes SU2 to diverge instantly. It runs fine with 6, but crashes at 15. I've attached two images showing that it is a mesh issue causing this (nothing else is being changed in the setup).

Other things such as reducing lcMin on Field[12] can also make it crash for example, however the above has visible errors in the mesh.

Does anyone have an idea on why I can't use the Distance/Threshold field as normal on this edge?

If you can provide any guidance that would be greatly appreciated, it's so close...! I've already tested with the latest release with the same results.

Thanks a lot,
Kind Regards,

Nathan Ricks






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