[mohsen.boojari]

Hi,
I want to create a cylindrical domain ( a wind Tunnel ) using blockMesh. but when I ran the checkMesh utility I got these errors :

 ***High aspect ratio cells found, Max aspect ratio: 5.82132516384e+99, number of cells 87120
  <<Writing 87120 cells with high aspect ratio to set highAspectRatioCells
    Minimum face area = 0.0173370986175. Maximum face area = 0.793420166088.  Face area magnitudes OK.
 ***Zero or negative cell volume detected.  Minimum negative volume: -0.232948349551, Number of negative volume cells: 87120
  <<Writing 87120 zero volume cells to set zeroVolumeCells
    Mesh non-orthogonality Max: 180 average: 159.098266664
 ***Number of non-orthogonality errors: 254364.
  <<Writing 254364 non-orthogonal faces to set nonOrthoFaces
 ***Error in face pyramids: 522720 faces are incorrectly oriented.
  <<Writing 268356 faces with incorrect orientation to set wrongOrientedFaces
    Max skewness = 3.71841074197 OK.
    Coupled point location match (average 0) OK.

Failed 4 mesh checks.

I have attached my blockMeshDict too. please see it.
can anyone help me to solve the problem?

thanks

convertToMeters 1;

vertices
(
    (-18  0  9) //0
    (-18  9  0) //1
    (-18  0 -9) //2
    (-18 -9  0) //3
    ( 36  0  9) //4
    ( 36  9  0) //5
    ( 36  0 -9) //6
    ( 36 -9  0) //7
);

blocks
(
    hex (0 1 2 3 4 5 6 7)  (200 66 66) simpleGrading (1 1 1)
   
);

boundary
(
    inlet
    {
        type patch;
        faces
        (
            (0 1 2 3)
        );
    }

    outlet
    {
    type patch;
    faces
        (
            (4 7 6 5)
        );
    }

    walls
    {
    type wall;
        faces
        (
            (1 5 4 0)
            (4 0 3 7)
            (3 7 6 2)
            (2 6 5 1)
        );
    }
);

edges
(
    arc 0 1 (-18  6.363961031  6.363961031)
    arc 1 2 (-18  6.363961031 -6.363961031)
    arc 2 3 (-18 -6.363961031 -6.363961031)
    arc 3 0 (-18 -6.363961031  6.363961031)
    arc 4 5 ( 36  6.363961031  6.363961031)
    arc 5 6 ( 36  6.363961031 -6.363961031)
    arc 6 7 ( 36 -6.363961031 -6.363961031)
    arc 7 4 ( 36 -6.363961031  6.363961031)
);

mergePatchPairs
(
);