Meshing fails for small size
Dear Gmsh-ers,
In the attached file, I define a mesh based on a given BREP CAD. The size of the elements are set in line 109 of the geo file with the rch_min variable. Everything is OK when the size is higher than 50. But when trying rch_min=20 or 10, the mesh fails. The CAD is quiet simple so I am quiet disappointed by this behaviour. I would expect the meshing problem to be simpler for smaller elements. Or does it reveal a problem in the CAD ? I have tried all the analysis tool I have and they tell me the CAD is file. Where is the problem ?
Thanks, NiKo
===================================================================== Example or error
Info : Running 'gmsh script_Domaine.geo -3 -format med -o myMesh.med' [Gmsh 4.7.0, 1 node, max. 1 thread]
Info : Started on Fri Jan 22 15:30:11 2021
Info : Reading 'script_Domaine.geo'...
Info : Reading 'Domaine_large.brep'...
Info : Done reading 'Domaine_large.brep'
Info : Removing duplicate mesh nodes...
Info : Found 0 duplicate nodes
Info : No duplicate nodes found
Info : Done reading 'script_Domaine.geo'
Info : Meshing 1D...
Info : [ 0%] Meshing curve 10 (BSpline)
Info : [ 10%] Meshing curve 17 (BSpline)
Info : [ 10%] Meshing curve 22 (BSpline)
Info : [ 10%] Meshing curve 23 (BSpline)
Info : [ 20%] Meshing curve 26 (BSpline)
Info : [ 20%] Meshing curve 28 (BSpline)
Info : [ 20%] Meshing curve 29 (Line)
Info : [ 20%] Meshing curve 30 (Line)
Info : [ 30%] Meshing curve 31 (Line)
Info : [ 30%] Meshing curve 32 (Line)
Info : [ 30%] Meshing curve 33 (Line)
Info : [ 30%] Meshing curve 34 (Line)
Info : [ 40%] Meshing curve 35 (Line)
Info : [ 40%] Meshing curve 36 (Line)
Info : [ 40%] Meshing curve 37 (Line)
Info : [ 40%] Meshing curve 38 (BSpline)
Info : [ 50%] Meshing curve 39 (BSpline)
Info : [ 50%] Meshing curve 40 (Line)
Info : [ 50%] Meshing curve 41 (Line)
Info : [ 50%] Meshing curve 42 (Line)
Info : [ 60%] Meshing curve 43 (BSpline)
Info : [ 60%] Meshing curve 44 (Line)
Info : [ 60%] Meshing curve 45 (BSpline)
Info : [ 70%] Meshing curve 46 (BSpline)
Info : [ 70%] Meshing curve 47 (BSpline)
Info : [ 70%] Meshing curve 48 (Line)
Info : [ 70%] Meshing curve 49 (Line)
Info : [ 80%] Meshing curve 50 (Line)
Info : [ 80%] Meshing curve 51 (Line)
Info : [ 80%] Meshing curve 52 (BSpline)
Info : [ 80%] Meshing curve 53 (BSpline)
Info : [ 90%] Meshing curve 54 (Line)
Info : [ 90%] Meshing curve 55 (Line)
Info : [ 90%] Meshing curve 56 (Line)
Info : [ 90%] Meshing curve 57 (Line)
Info : [100%] Meshing curve 58 (Line)
Info : [100%] Meshing curve 59 (Line)
Info : [100%] Meshing curve 60 (Line)
Info : Done meshing 1D (Wall 0.248441s, CPU 0.246137s)
Info : Meshing 2D...
Info : [ 0%] Meshing surface 8 (BSpline surface, Frontal-Delaunay)
Info : [ 10%] Meshing surface 13 (BSpline surface, Frontal-Delaunay)
Info : [ 20%] Meshing surface 15 (Plane, Frontal-Delaunay)
Info : [ 20%] Meshing surface 16 (Plane, Frontal-Delaunay)
Info : [ 30%] Meshing surface 17 (Plane, Frontal-Delaunay)
Info : [ 30%] Meshing surface 18 (Plane, Frontal-Delaunay)
Info : [ 40%] Meshing surface 19 (Plane, Frontal-Delaunay)
Info : [ 40%] Meshing surface 20 (Plane, Frontal-Delaunay)
Info : [ 50%] Meshing surface 21 (Plane, Frontal-Delaunay)
Info : [ 50%] Meshing surface 22 (Plane, Frontal-Delaunay)
Info : [ 60%] Meshing surface 23 (Plane, Frontal-Delaunay)
Info : [ 60%] Meshing surface 24 (BSpline surface, Frontal-Delaunay)
Info : [ 70%] Meshing surface 25 (BSpline surface, Frontal-Delaunay)
Info : [ 70%] Meshing surface 26 (Plane, Frontal-Delaunay)
Info : [ 80%] Meshing surface 27 (Plane, Frontal-Delaunay)
Info : [ 80%] Meshing surface 28 (Plane, Frontal-Delaunay)
Info : [ 90%] Meshing surface 29 (Plane, Frontal-Delaunay)
Info : [ 90%] Meshing surface 30 (Plane, Frontal-Delaunay)
Info : [100%] Meshing surface 31 (Plane, Frontal-Delaunay)
Info : Done meshing 2D (Wall 10.9206s, CPU 10.8586s)
Info : Meshing 3D...
Info : 3D Meshing 3 volumes with 1 connected component
Info : Creating an empty mesh with 174626 vertices
Info : Initialization of tet. mesh
Info : Delaunay of 174622 points on 1 threads - mesh.nvert: 4
Info : Recovering 425 missing facet(s)
Found two exactly self-intersecting facets.
1st: [7095, 6922, 53671] #13
2nd: [7095, 6922, 82533] #24
Info : failed to recover constrained lines/triangles
Error : HXT 3D mesh failed
Error : No elements in volume 1 2 3
Info : Done meshing 3D (Wall 2.6378s, CPU 2.45588s)
Info : Meshing order 2 (curvilinear on)...
Info : [ 0%] Meshing curve 10 order 2
Info : [ 10%] Meshing curve 17 order 2
Info : [ 10%] Meshing curve 22 order 2
Info : [ 10%] Meshing curve 23 order 2
Info : [ 10%] Meshing curve 26 order 2
Info : [ 10%] Meshing curve 28 order 2
Info : [ 10%] Meshing curve 29 order 2
Info : [ 20%] Meshing curve 30 order 2
Info : [ 20%] Meshing curve 31 order 2
Info : [ 20%] Meshing curve 32 order 2
Info : [ 20%] Meshing curve 33 order 2
Info : [ 20%] Meshing curve 34 order 2
Info : [ 20%] Meshing curve 35 order 2
Info : [ 30%] Meshing curve 36 order 2
Info : [ 30%] Meshing curve 37 order 2
Info : [ 30%] Meshing curve 38 order 2
Info : [ 30%] Meshing curve 39 order 2
Info : [ 30%] Meshing curve 40 order 2
Info : [ 30%] Meshing curve 41 order 2
Info : [ 40%] Meshing curve 42 order 2
Info : [ 40%] Meshing curve 43 order 2
Info : [ 40%] Meshing curve 44 order 2
Info : [ 40%] Meshing curve 45 order 2
Info : [ 40%] Meshing curve 46 order 2
Info : [ 40%] Meshing curve 47 order 2
Info : [ 50%] Meshing curve 48 order 2
Info : [ 50%] Meshing curve 49 order 2
Info : [ 50%] Meshing curve 50 order 2
Info : [ 50%] Meshing curve 51 order 2
Info : [ 50%] Meshing curve 52 order 2
Info : [ 50%] Meshing curve 53 order 2
Info : [ 60%] Meshing curve 54 order 2
Info : [ 60%] Meshing curve 55 order 2
Info : [ 60%] Meshing curve 56 order 2
Info : [ 60%] Meshing curve 57 order 2
Info : [ 60%] Meshing curve 58 order 2
Info : [ 60%] Meshing curve 59 order 2
Info : [ 70%] Meshing curve 60 order 2
Info : [ 70%] Meshing surface 8 order 2
Info : [ 70%] Meshing surface 13 order 2
Info : [ 70%] Meshing surface 15 order 2
Info : [ 70%] Meshing surface 16 order 2
Info : [ 70%] Meshing surface 17 order 2
Info : [ 80%] Meshing surface 18 order 2
Info : [ 80%] Meshing surface 19 order 2
Info : [ 80%] Meshing surface 20 order 2
Info : [ 80%] Meshing surface 21 order 2
Info : [ 80%] Meshing surface 22 order 2
Info : [ 80%] Meshing surface 23 order 2
Info : [ 90%] Meshing surface 24 order 2
Info : [ 90%] Meshing surface 25 order 2
Info : [ 90%] Meshing surface 26 order 2
Info : [ 90%] Meshing surface 27 order 2
Info : [ 90%] Meshing surface 28 order 2
Info : [ 90%] Meshing surface 29 order 2
Info : [100%] Meshing surface 30 order 2
Info : [100%] Meshing surface 31 order 2
Info : [100%] Meshing volume 1 order 2
Info : [100%] Meshing volume 2 order 2
Info : [100%] Meshing volume 3 order 2
Warning : Surface mesh: worst distortion = 0 (avg = 0.999942, 0 elements with jac. < 0); worst gamma = 0
Info : Done meshing order 2 (Wall 82.7178s, CPU 82.4999s)
Info : 700067 nodes 354136 elements
Error : ------------------------------
Error : Mesh generation error summary
Error : 1 warning
Error : 2 errors
Error : Check the full log for details
Error : ------------------------------
Info : Writing 'myMesh.med'...
Info : Done writing 'myMesh.med'
Info : Stopped on Fri Jan 22 15:31:56 2021 (From start: Wall 105.044s, CPU 104.971s)
Edited by Christophe Geuzaine