Ignore the StarCCM+ Warning. We have tested the process also with Pointwise, GMSH meshes. What mesh generator do you use?
What this means - a vertex of your linear straight-sided mesh is too far away from the CAD STEP file.
- Your linear mesh generator has decided not follow the CAD definition. I have noticed this happening around Trailing edges, where they will just collapse the TE face for some reason ( for example h_min > h_TE) .
- When generating coarse meshes, some Finite Volume Mesh generators seem to be relatively inaccurate.
- Your STEP file and the linear mesh are in different units.
- You are meshing from a triangulation (EX: STL ) that is too far away from the original STEP.
Either way, you need to make sure that the linear mesh is within tolerance away from the CAD file.
You can try to check if the coordinates of your linear mesh in the XML by : NekMesh mesh.xml mesh.xml:xml:uncompress
Alternatively, you can visualize in Paraview and make sure that they are the expected values with: FieldConvert mesh.xml mesh.vtu -n 2
If all these checks are passed, try to analyze your linear mesh if something is wrong there. Maybe increase the resolution as well.
I hope this helps.
Kind Regards,
Kaloyan