[ant_mnr]

Hi everyone,


I am trying to simulate a supersonic flow around a body. To do so, I import the geometry using an .ftr file (like STL but better organized) and use cfMesh to first create an axisymmetric cartesian 3D mesh, and then convert it into 2D using extrudeMesh. In order have the lowest y+ value, I need very close boundary layers. The problem is that for levels higher than 7, checkMesh returns errors like bellow.



> For level 8:
"Checking geometry...
Overall domain bounding box (-0.328 -6.48774e-19 -0.00691115) (0.6888 0.39594 0.00691115)
Mesh has 2 geometric (non-empty/wedge) directions (1 1 0)
Mesh has 3 solution (non-empty) directions (1 1 1)
Wedge back with angle 1 degrees
***Wedge patch back not planar. Point (-0.319643 0.127955 -0.00223345) is not in patch plane by 1.56481e-08 metre.
Boundary openness (-2.24551e-17 2.68994e-16 -1.20287e-13) OK.
Max cell openness = 4.51902e-16 OK.
Max aspect ratio = 19.1187 OK.
Minimum face area = 5.0473e-25. Maximum face area = 0.000151092. Face area magnitudes OK.
Min volume = 3.60385e-17. Max volume = 1.33865e-06. Total volume = 0.00278237. Cell volumes OK.
Mesh non-orthogonality Max: 77.4471 average: 2.67348
*Number of severely non-orthogonal (> 70 degrees) faces: 4.
Non-orthogonality check OK.
<<Writing 4 non-orthogonal faces to set nonOrthoFaces
Face pyramids OK.
***Max skewness = 2684.93, 19 highly skew faces detected which may impair the quality of the results
<<Writing 19 skew faces to set skewFaces
Coupled point location match (average 0) OK.

Failed 2 mesh checks."


> For level 9 and higher:
"Checking geometry...
Overall domain bounding box (-0.328 -4.21854e-19 -0.00691115) (0.6888 0.39594 0.00691115)
Mesh has 2 geometric (non-empty/wedge) directions (1 1 0)
Mesh has 3 solution (non-empty) directions (1 1 1)
Wedge back with angle 1 degrees
Wedge front with angle 1 degrees
***Number of edges not aligned with or perpendicular to non-empty directions: 15
<<Writing 30 points on non-aligned edges to set nonAlignedEdges
Boundary openness (2.3265e-19 -6.06425e-17 -9.24456e-16) OK.
Max cell openness = 7.18091e-16 OK.
Max aspect ratio = 25.3017 OK.
***Zero or negative face area detected. Minimum area: 0
<<Writing 15 zero area faces to set zeroAreaFaces
Min volume = 2.70223e-18. Max volume = 1.41637e-06. Total volume = 0.00278236. Cell volumes OK.
Mesh non-orthogonality Max: 90 average: 5.92746
*Number of severely non-orthogonal (> 70 degrees) faces: 6.
***Number of non-orthogonality errors: 15.
<<Writing 21 non-orthogonal faces to set nonOrthoFaces
Face pyramids OK.
***Max skewness = 614.052, 26 highly skew faces detected which may impair the quality of the results
<<Writing 26 skew faces to set skewFaces
Coupled point location match (average 0) OK.

Failed 4 mesh checks."


I tried to make a 2D mesh and then extrude it, refine my STL file using CATIA, use poly or tetrahedral cells ... Nothing is working.



Can anyone help me to resolve that problem please ?


Thank you.