[Edoardo1993]

Hello, I am new with OF and I need to use blockMesh to create a domain with 2 regions: one external and one internal with finer mesh. In particular, the domain is formed by two blocks:

1) internally a parallelepiped with fine mesh;

2) externally a parallelepiped with a less dense mesh;
(Look at the attached picture).


Here it is my blockMeshDict.

 vertices
(

    (0 0 0)           //0
    (10 0 0)        //1
    (10 10 0)      //2
    (0 10 0)        //3
    (0 0 10)        //4
    (10 0 10)      //5
    (10 10 10)    //6
    (0 10 10)      //7

    (0 4 4)        //8
    (10 4 4)      //9
    (10 6 4)      //10
    (0 6 4)        //11
    (0 4 6)        //12
    (10 4 6)        //13
    (10 6 6)        //14
    (0 6 6)        //15
);

blocks
(
    hex (0 1 2 3 4 5 6 7) (20 20 20) simpleGrading (1 1 1)
    hex (8 9 10 11 12 13 14 15) (100 100 100) simpleGrading (1 1 1)
);


edges
(
);

boundary
(
    inlet
    {
        type patch;
        faces
        (
            (7 3 0 4)
            (15 11 8 12)
    
        );
    }

    outlet
    {
        type patch;
        faces
        (
            (1 2 6 5)
            (9 10 14 13)
    
        );
    }

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

);

mergePatchPairs
(
 );

My problems are:
1) Why the inner block has 4 external faces? I want those faces (13 14 15 12) (15 14 10 11) (9 8 11 10) (12 8 9 13) to be internal.
2) How to joint the mesh at the interface to have continuity?



Thank you for your help