Block Mesh Problem
 

Hello all. I have another beginner's question that hopefully someone can answer. Sorry if this has been answered before, but I haven't had much luck finding a solution on-line.

I recently tried to create a mesh using blockMesh, but when I used checkMesh, I saw the following in my terminal:


Create time

Create polyMesh for time = 0

Time = 0

Mesh stats
points: 1926404
internal points: 0
faces: 3843200
internal faces: 1916800
cells: 960000
faces per cell: 6
boundary patches: 5
point zones: 0
face zones: 0
cell zones: 0

Overall number of cells of each type:
hexahedra: 960000
prisms: 0
wedges: 0
pyramids: 0
tet wedges: 0
tetrahedra: 0
polyhedra: 0

Checking topology...
Boundary definition OK.
***Total number of faces on empty patches is not divisible by the number of cells in the mesh. Hence this mesh is not 1D or 2D.
Cell to face addressing OK.
Point usage OK.
Upper triangular ordering OK.
Face vertices OK.
*Number of regions: 2
The mesh has multiple regions which are not connected by any face.
<<Writing region information to "0/cellToRegion"

Checking patch topology for multiply connected surfaces...
Patch Faces Points Surface topology
inlet 800 1604 ok (non-closed singly connected)
outlet 800 1604 ok (non-closed singly connected)
top 2400 4804 ok (non-closed singly connected)
obstacle 1600 3204 ok (non-closed singly connected)
defaultFaces 1920800 1926404 ok (non-closed singly connected)

Checking geometry...
Overall domain bounding box (-0.15242 -0.1524 -0.005) (0.3048 0.1524 0.005)
Mesh (non-empty, non-wedge) directions (1 0 0)
Mesh (non-empty) directions (1 0 0)
***Number of edges not aligned with or perpendicular to non-empty directions: 1280000
<<Writing 1281600 points on non-aligned edges to set nonAlignedEdges
Boundary openness (-4.51238858e-17 -5.21277638e-16 -1.04746924e-17) OK.
Max cell openness = 2.2798214e-16 OK.
Max aspect ratio = 1 OK.
Minimum face area = 6.74180643e-08. Maximum face area = 3.94440227e-06. Face area magnitudes OK.
Min volume = 2e-300. Max volume = 1.4518005e-09. Total volume = 0.000572336807. Cell volumes OK.
Mesh non-orthogonality Max: 180 average: 90
***Number of non-orthogonality errors: 958400.
<<Writing 958400 non-orthogonal faces to set nonOrthoFaces
***Error in face pyramids: 2880000 faces are incorrectly oriented.
<<Writing 1921600 faces with incorrect orientation to set wrongOrientedFaces
Max skewness = 0.576767172 OK.
Coupled point location match (average 0) OK.

Failed 3 mesh checks.

End




Can someone tell me what 3 mesh checks failed? I see that there was an error in face pyramids, but I'm not sure if that is one of the mesh checks that failed. In case it might be helful, I will post my blockMeshDict below:

convertToMeters 1;

vertices
(
(-0.15242 0 -0.005)//0
( 0 0 -0.005)//1
( 0.3048 0.081670913853 -0.005)//2
(-0.15242 0.1524 -0.005)//3
( 0 0.1524 -0.005)//4
( 0.3048 0.1524 -0.005)//5

(-0.15242 0 0.005)//6
( 0 0 0.005)//7
( 0.3048 0.081670913853 0.005)//8
(-0.15242 0.1524 0.005)//9
( 0 0.1524 0.005)//10
( 0.3048 0.1524 0.005)//11

(-0.15242 0 -0.005)//12 0-2
( 0 0 -0.005)//13 1-2
( 0.3048 -0.081670913853 -0.005)//14 2-2
(-0.15242 -0.1524 -0.005)//15 3-2
( 0 -0.1524 -0.005)//16 4-2
( 0.3048 -0.1524 -0.005)//17 5-2

(-0.15242 0 0.005)//18 6-2
( 0 0 0.005)//19 7-2
( 0.3048 -0.081670913853 0.005)//20 8-2
(-0.15242 -0.1524 0.005)//21 9-2
( 0 -0.1524 0.005)//22 10-2
( 0.3048 -0.1524 0.005)//23 11-2

);

blocks
(
hex (0 1 4 3 6 7 10 9 ) (400 400 1) simpleGrading (1 1 1)
hex (1 2 5 4 7 8 11 10) (800 400 1) simpleGrading (1 1 1)
hex (12 13 16 15 18 19 22 21) (400 400 1) simpleGrading (1 1 1)
hex (13 14 17 16 19 20 23 22) (800 400 1) simpleGrading (1 1 1)
);

edges
(
);

boundary
(
inlet
{
type patch;
faces
(
(0 6 9 3)
(12 18 21 15)
);
}
outlet
{
type patch;
faces
(
(2 5 11 8)
(14 17 23 20)
);
}
top
{
type symmetryPlane;
faces
(
(3 9 10 4)
(4 10 11 5)
(15 21 22 16)
(16 22 23 17)
);
}
obstacle
{
type patch;
faces
(
(1 2 8 7)
(13 14 20 19)
);
}
);

mergePatchPairs
(
);


Thanks for any help you might have for me.