CFD Online Discussion Forums - [blockMesh] Very simple case, weird blockMesh

Hi,

I want to create a box. My blockMesh code is:

Code:

convertToMeters 1;



vertices

(

    ( 581895  4785760  1038)

    ( 581895  4785760  1060)

    ( 581775  4785760  1060)

    ( 581775  4785760  1038)

    ( 581895  4785880  1038)

    ( 581895  4785880  1060)

    ( 581775  4785880  1060)

    ( 581775  4785880  1038)

);



blocks

(

    hex (0 1 2 3 4 5 6 7) (10 20 20) simpleGrading (10.0 1 1)

//    hex (0 1 2 3 4 5 6 7) (6 6 6) simpleGrading (10.0 1 1)

);



edges

(

);



boundary

(

    maxX

    {

        type patch;

        faces

        (

            (3 7 6 2)

        );

    }

    minZ

    {

        type patch;

        faces

        (

            (0 4 7 3)

        );

    }

    maxZ

    {

        type patch;

        faces

        (

            (2 6 5 1)

        );

    }

    minX

    {

        type patch;

        faces

        (

            (1 5 4 0)

        );

    }

    minY

    {

        type patch;

        faces

        (

            (0 3 2 1)

        );

    }

    maxY

    {

        type patch;

        faces

        (

            (4 5 6 7)

        );

    }

);



mergePatchPairs

(

);

You can see it very very simple. But I got errors:

Code:

Checking geometry...

    Overall domain bounding box (581775 4.78576e+06 1038) (581895 4.78588e+06 1060)

    Mesh (non-empty, non-wedge) directions (1 1 1)

    Mesh (non-empty) directions (1 1 1)

    Boundary openness (4.04186e-17 3.46606e-17 0) OK.

 ***High aspect ratio cells found, Max aspect ratio: 2.11238e+201, number of cells 4000

  <<Writing 4000 cells with high aspect ratio to set highAspectRatioCells

    Minimum face area = 3.22979. Maximum face area = 36.  Face area magnitudes OK.

    Min volume = 2e-300. Max volume = 2e-300.  Total volume = 8e-297.  Cell volumes OK.

    Mesh non-orthogonality Max: 180 average: 180

 ***Number of non-orthogonality errors: 11200.

  <<Writing 11200 non-orthogonal faces to set nonOrthoFaces

 ***Error in face pyramids: 24000 faces are incorrectly oriented.

  <<Writing 12800 faces with incorrect orientation to set wrongOrientedFaces

    Max skewness = 4.32531e-09 OK.

    Coupled point location match (average 0) OK.



Failed 3 mesh checks.

Any ideas? Thanks.