BIG Problem in extrudeMesh!
 

Dear all,

I use extrudeMesh to extrude one layer of a patch from my existing 3D case for 2D simpleFoam running.

However, I execute 'checkMesh' after 'extrudeMesh', there are three errors:


Create time
Create polyMesh for time = constant
Time = constant
Mesh stats
points: 48932
faces: 96382
internal faces: 47730
cells: 23972
boundary patches: 7
point zones: 0
face zones: 0
cell zones: 0
Number of cells of each type:
hexahedra: 23736
prisms: 0
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 236
Checking topology...
Boundary definition OK.
Point usage OK.
Upper triangular ordering OK.
Topological cell zip-up check OK.
Face vertices OK.
Face-face connectivity OK.
Number of regions: 1 (OK).
Checking patch topology for multiply connected surfaces ...
Patch Faces Points Surface
inlet 132 266 ok (not multiply connected)
right 142 286 ok (not multiply connected)
outlet 132 266 ok (not multiply connected)
bldg 160 320 ok (not multiply connected)
left 142 286 ok (not multiply connected)
up 23972 24466 ok (not multiply connected)
bottom 23972 24466 ok (not multiply connected)
Checking geometry...
Domain bounding box: (0 0 -0.05) (3.375 2.625 0)
Boundary openness (-1.0894e-18 2.60509e-18 -1.19683e-13) OK.
***High aspect ratio cells found, Max aspect ratio: 1.59258e+197, number of cells 23972
<<Writing 23972 cells with high aspect ratio to set highAspectRatioCells
Minumum face area = 8.55504e-06. Maximum face area = 0.0033015. Face area magnitudes OK.
Min volume = 2e-300. Max volume = 2.66667e-300. Total volume = 4.80373e-296. Cell volumes OK.
Mesh non-orthogonality Max: 180 average: 177.794
***Number of non-orthogonality errors: 47730.
<<Writing 47730 non-orthogonal faces to set nonOrthoFaces
***Error in face pyramids: 144112 faces are incorrectly oriented.
<<Writing 96382 faces with incorrect orientation to set wrongOrientedFaces
Max skewness = 0.455711 OK.
All angles in faces OK.
Face flatness (1 = flat, 0 = butterfly) : average = 1 min = 1
All face flatness OK.
Failed 3 mesh checks.
End


Can anyone tell me what problems these are and how can I solve them?

Thx,

Wind_fyp.