[mostafa kamal]

hello everyone
iam trying to make a mesh domain as in 2.png using blockmesh ,but with 6 vertices instead of 8 vertices
i did so using the documentation of blockmesh utility but when i view the mesh on paraview it appears as shown in figures in the inlet and outlet there is a fine mesh at vertex 4 as shown
when i make checkmesh it tells me that the most of the mesh(7600) is hexahedra and a few is prisms (only 400)

my blockmeshDict is
/*--------------------------------*- C++ -*----------------------------------*\
========= |
\\ / F ield | OpenFOAM: The Open Source CFD Toolbox
\\ / O peration | Website: https://openfoam.org
\\ / A nd | Version: 6
\\/ M anipulation |
\*---------------------------------------------------------------------------*/
FoamFile
{
version 2.0;
format ascii;
class dictionary;
object blockMeshDict;
}

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

convertToMeters 1;

vertices
(
( 0.000 0.000 0.000) // vertrex no 0
( 0.000 0.000 -110)
( -30 17.5 -110)
( -30 17.5 0.000)
( 30 17.5 0.000)
( 30 17.5 -110)



);

blocks
(
hex ( 0 1 2 3 4 5 5 4 ) (20 20 20) simpleGrading (1 1 1)
);

edges
(
arc 3 4 ( 0 35 0)
arc 2 5 ( 0 35 -110 )
);

boundary
(
inlet
{
type patch;
faces
(
(0 4 4 3)
);
}
outlet
{
type patch;
faces
(
(5 1 2 5)
);
}

outerWall
{
type wall;
faces
(
(3 4 5 2)
);
}
cyclic_half0
{
type cyclic;
neighbourPatch cyclic_half1;
transform rotational;
rotationAxis (0 0 1);
rotationCentre (0 0 0);
faces
(
(1 0 3 2 )
);
}
cyclic_half1
{
type cyclic;
neighbourPatch cyclic_half0;
transform rotational;
rotationAxis (0 0 1);
rotationCentre (0 0 0);
faces
(
(0 1 5 4)
);
}
);

mergeMatchPairs
(
);

// ************************************************** *********************** //


how can i solve this problem to make a uniform mesh as i dersire ?
thank you

[yambanshee]

You are collapsing on the wrong vertices. Where you define your block

hex ( 0 1 2 3 4 5 5 4 ) (20 20 20) simpleGrading (1 1 1)

you can see that the repeating vertices that you use are 4 and 5, which corresponds to the vertices on the top right of your block.

Based on your description, you want to collapse the vertices 0 and 1, and so your block needs to be rewritten as

hex ( 5 4 3 2 1 0 0 1 ) (20 20 20) simpleGrading (1 1 1)

Edit:
Your inlet and outlet patches also look wrongly defined. You might need to edit these