******************* This email originates from outside Imperial. Do not click on links and attachments unless you recognise the sender. If you trust the sender, add them to your safe senders list https://spam.ic.ac.uk/SpamConsole/Senders.aspx to disable email stamping for this address. ******************* Hello everyone, since NekMesh doesn't seem to like my 3D mesh generated with ICEM and Gmsh (see thread "NekMesh: Inconsistent triangular face orientation"), I tried creating it directly with NekMesh by using a mesh configuration file or mcf ("mesh_configuration_file.txt"). However, this doesn't properly work either when I activate the boundary layer refinement or blr feature. I attached all the necessary files converted to txt. I provided the geometry as *.step ("cylinder_geom_step_file1.txt") to the mcf and it works without blr. As soon as I switch on blr it throws the following warning, aborting the volume meshing process: Fatal : Level 0 assertion violation not setup for curve bl refinement [InputMCF] WARNING: Volume meshing has failed with message: [InputMCF] WARNING: Level 0 assertion violation not setup for curve bl refinement [InputMCF] WARNING: The linear surface mesh be written as a manifold mesh If I include all the domain boundaries except for the two side faces along the cylinder axis, i.e. writing <P PARAM="BndLayerSurfaces" VALUE="1,2,3,4,6,7,8,9" /> with 5 and 10 being the two side faces, it works. But obviously, I only need blr on the cylinder surface and not anywhere else. In a second attempt I loaded the geometry into Gmsh first, defined all the physical groups ("geo_file.txt") and again exported as *.step ("cylinder_geom_step_file2.txt"). This doesn't work at all, neither with nor without blr activated in the mcf and produces the following warning before crashing entirely: Fatal : Level 0 assertion violation surface mesh connectivity error [InputMCF] WARNING: Surface meshing has failed with message: [InputMCF] WARNING: Level 0 assertion violation surface mesh connectivity error [InputMCF] WARNING: Any surfaces which were successfully meshed will be written as a manifold mesh. [InputMCF] - Elapsed time: 4.78223s. [OutputNekpp] Writing Nektar++ file 'CylReD3900_3D_G1.xml' Fatal : Level 0 assertion violation Connected edges do not share a vertex. Edges 2347, 2345 terminate called after throwing an instance of 'Nektar::ErrorUtil::NekError' what(): Level 0 assertion violation Connected edges do not share a vertex. Edges 2347, 2345 Any help is very mush appreciated. All the best Alex Sicher versendet mit [Proton Mail](https://proton.me/).