CFD Online Discussion Forums - [blockMesh] How to create a T-junction cylinder with blockMesh

Quote:

Originally Posted by Blanca (Post 675722)

Hi,

I am trying to create a T-junction cylinder with blockMesh, but I don't know how to do it. I created first one single cylinder, so I wonder if I can mix two cylinders? Because I didn't read anything about doing it with OpenFOAM, most people did it by ANSYS or other programs.
Could anyone help me?

Thanks

If you are like me and prefer using open source solutions, then I can recommend gsmh which would be more than enough for what you want. However, I am not sure if it can produce structured meshes.

Incidentally, I am also trying to achieve a similar thing using blockMesh. I came across the following blockMeshDict posted by another user on this forum. It is missing O-grid in one of the blocks and I am working with this file to improve the mesh and integrating it in my geometry. However, it is a good base on which you can work as well.

Code:

/*--------------------------------*- C++ -*----------------------------------*\

| =========                 |                                                 |

| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |

|  \\    /   O peration     | Version:  4.1                                   |

|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |

|    \\/     M anipulation  |                                                 |

\*---------------------------------------------------------------------------*/

FoamFile

{

    version     2.0;

    format      ascii;

    class       dictionary;

    object      blockMeshDict;

}

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



convertToMeters 1e-2;

vertices

(

( 0.100000 -0.100000 0.000000)

( -0.100000 -0.100000 0.000000)

( -0.100000 0.100000 0.000000)

( 0.100000 0.100000 0.000000)

( 0.141421 -0.141421 0.000000)

( -0.141421 -0.141421 0.000000)

( -0.141421 0.141421 0.000000)

( 0.141421 0.141421 0.000000)

( 0.100000 -0.100000 1.000000)

( -0.100000 -0.100000 1.000000)

( -0.100000 0.100000 1.000000)

( 0.100000 0.100000 1.000000)

( 0.141421 -0.141421 1.000000)

( -0.141421 -0.141421 1.000000)

( -0.141421 0.141421 1.000000)

( 0.141421 0.141421 1.000000)



( 0.050000 -0.183333 0.450000)

( -0.050000 -0.183333 0.450000)

( -0.050000 -0.183333 0.550000)

( 0.050000 -0.183333 0.550000)

( 0.070711 -0.183333 0.429289)

( -0.070711 -0.183333 0.429289)

( -0.070711 -0.183333 0.570711)

( 0.070711 -0.183333 0.570711)

( 0.050000 -1.183333 0.450000)

( -0.050000 -1.183333 0.450000)

( -0.050000 -1.183333 0.550000)

( 0.050000 -1.183333 0.550000)

( 0.070711 -1.183333 0.429289)

( -0.070711 -1.183333 0.429289)

( -0.070711 -1.183333 0.570711)

( 0.070711 -1.183333 0.570711)



);

blocks

(

//block0

hex (1 0 3 2 9 8 11 10)

square

(5 5 50)

simpleGrading (1 1 1)



//block1

hex (0 4 7 3 8 12 15 11)

innerCircle

(5 5 50)

simpleGrading (1 1 1)



//block2

hex (3 7 6 2 11 15 14 10)

innerCircle

(5 5 50)

simpleGrading (1 1 1)



//block3

hex (2 6 5 1 10 14 13 9)

innerCircle

(5 5 50)

simpleGrading (1 1 1)



//block4

hex (1 5 4 0 9 13 12 8)

innerCircle

(5 5 50)

simpleGrading (1 1 1)



//block5

hex ( 17 16 19 18 25 24 27 26 )

square

(5 5 10)

simpleGrading (1 1 1)



//block5

hex ( 16 20 23 19 24 28 31 27 )

innerCircle

(5 5 10)

simpleGrading (1 1 1)



//block7

hex ( 19 23 22 18 27 31 30 26 )

innerCircle

(5 5 10)

simpleGrading (1 1 1)



//block8

hex ( 18 22 21 17 26 30 29 25 )

innerCircle

(5 5 10)

simpleGrading (1 1 1)



//block9

hex ( 17 21 20 16 25 29 28 24 )

innerCircle

(5 5 10)

simpleGrading (1 1 1)



);

edges

(



arc 7 4 ( 0.200000 0.000000 0.000000)

arc 4 5 ( 0.000000 -0.200000 0.000000)

arc 5 6 ( -0.200000 0.000000 0.000000)

arc 6 7 ( 0.000000 0.200000 0.000000)

arc 15 12 ( 0.200000 0.000000 1.000000)

arc 12 13 ( 0.000000 -0.200000 1.000000)

arc 13 14 ( -0.200000 0.000000 1.000000)

arc 14 15 ( 0.000000 0.200000 1.000000)

arc 3 0 ( 0.110000 0.000000 0.000000)

arc 0 1 ( 0.000000 -0.110000 0.000000)

arc 1 2 ( -0.110000 0.000000 0.000000)

arc 2 3 ( 0.000000 0.110000 0.000000)

arc 11 8 ( 0.110000 0.000000 1.000000)

arc 8 9 ( 0.000000 -0.110000 1.000000)

arc 9 10 ( -0.110000 0.000000 1.000000)

arc 10 11 ( 0.000000 0.110000 1.000000)



arc 23 20 ( 0.100000 -0.183333 0.500000)

arc 20 21 ( 0.000000 -0.183333 0.400000)

arc 21 22 ( -0.100000 -0.183333 0.500000)

arc 22 23 ( 0.000000 -0.183333 0.600000)

arc 31 28 ( 0.100000 -1.183333 0.500000)

arc 28 29 ( 0.000000 -1.183333 0.400000)

arc 29 30 ( -0.100000 -1.183333 0.500000)

arc 30 31 ( 0.000000 -1.183333 0.600000)

arc 19 16 ( 0.060000 -0.183333 0.500000)

arc 16 17 ( 0.000000 -0.183333 0.440000)

arc 17 18 ( -0.060000 -0.183333 0.500000)

arc 18 19 ( 0.000000 -0.183333 0.560000)

arc 27 24 ( 0.060000 -1.183333 0.500000)

arc 24 25 ( 0.000000 -1.183333 0.440000)

arc 25 26 ( -0.060000 -1.183333 0.500000)

arc 26 27 ( 0.000000 -1.183333 0.560000)



);

patches

(

wall

walls

(

(3 0 1 2)

(3 7 4 0)

(2 6 7 3)

(1 5 6 2)

(0 4 5 1)



(4 7 15 12)

(6 5 13 14)

(7 6 14 15)



( 20 23 31 28 )

( 21 20 28 29 )

( 22 21 29 30 )

( 23 22 30 31 )



)



patch

inlet

(

( 27 26 25 24 )

( 27 24 28 31 )

( 26 27 31 30 )

( 25 26 30 29 )

( 24 25 29 28 )

)



patch

outlet

(

(11 10 9 8)

(11 8 12 15)

(10 11 15 14)

(9 10 14 13)

(8 9 13 12)

)

patch

masterPatch

(

( 19 16 17 18 )

( 19 23 20 16 )

( 18 22 23 19 )

( 17 21 22 18 )

( 16 20 21 17 )

)

wall

mergewall

(

(5 4 12 13)

)



);



mergePatchPairs

(

(masterPatch mergewall)

);