[GFarello]

Hi everybody,

I have a very simple hexahedral fluid domain formed by an inlet, an outlet and four side walls. An object is included in this domain and my intention is to study the flow through this object using the Immersed Boundary Method.
Up to now everything works fine but, instead of having four solid side walls, I would like to set the patch type to cyclic (for the side walls) in order to simulate a periodic boundary.
I set the blockMeshDict as follows

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | foam-extend: Open Source CFD                    |
|  \\    /   O peration     | Version:     3.2                                |
|   \\  /    A nd           | Web:         http://www.foam-extend.org         |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/

FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      blockMeshDict;
}


convertToMeters 1;

vertices
(
    (-112 0 0)
    (336 0 0)
    (336 56 0)
    (-112 56 0)
    (-112 0 28)
    (336 0 28)
    (336 56 28)
    (-112 56 28) 
);

blocks
(
  hex (0 1 2 3 4 5 6 7) (448 56 28) simpleGrading (1 1 1)
);

boundary
(
    in
    {
      type patch;
      faces ((0 4 7 3));
    }
    out
    {
      type patch;
      faces ((2 6 5 1));
    }
    lato1
    {
      type cyclic;
      neighbourPatch lato2;
      faces ((0 1 2 3));
      matchTolerance 0.01;
    } 
    lato2
    {
      type cyclic;
      neighbourPatch lato1;
      faces ((4 5 6 7));
      matchTolerance 0.01;
    }  
    lato3
    {
      type cyclic;
      neighbourPatch lato4;
      faces ((0 4 5 1));
      matchTolerance 0.01;
    }
    lato4
    {
      type cyclic;
      neighbourPatch lato3;
      faces ((3 7 6 2));
      matchTolerance 0.01;
    }  
);

If I run blockMesh i get this message:

/*---------------------------------------------------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | foam-extend: Open Source CFD                    |
|  \\    /   O peration     | Version:     3.2                                |
|   \\  /    A nd           | Web:         http://www.foam-extend.org         |
|    \\/     M anipulation  | For copyright notice see file Copyright         |
\*---------------------------------------------------------------------------*/
Build    : 3.2-5ab3390aef43
Exec     : blockMesh
Date     : Oct 28 2016
Time     : 12:19:16
Host     : JM's_NB
PID      : 4946
CtrlDict : "/home/amedeo/Scrivania/Documenti/ibNew/system/controlDict"
Case     : /home/amedeo/Scrivania/Documenti/ibNew
nProcs   : 1
SigFpe   : Enabling floating point exception trapping (FOAM_SIGFPE).

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time


Creating block mesh from
    "/home/amedeo/Scrivania/Documenti/ibNew/constant/polyMesh/blockMeshDict"

No non-linear edges defined
Creating topology blocks
Creating topology patches

Creating block mesh topology
Segmentation fault (core dumped)

I also tried to set the blockMeshDict with only patches without any specification on the nature of the boundaries and then setting the cyclic patches in the boundary file;
in this case blockMesh works (obviously...) but i get the same message error (segmentation fault) in the solver log (i.e. potentialIBFoam).

I really don't understand what's wrong because the error message is too generic but maybe I'm doing some trivial mistake.

[milad653279]

Hi

I have the same problem, any response????

[GFarello]

Hi,

this should work:

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | foam-extend: Open Source CFD                    |
|  \\    /   O peration     | Version:     3.2                                |
|   \\  /    A nd           | Web:         http://www.foam-extend.org         |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/

FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      blockMeshDict;
}


convertToMeters 1;

vertices
(
    (-112 0 0)
    (336 0 0)
    (336 56 0)
    (-112 56 0)
    (-112 0 28)
    (336 0 28)
    (336 56 28)
    (-112 56 28) 
);

blocks
(
  hex (0 1 2 3 4 5 6 7) (448 56 28) simpleGrading (1 1 1)
);

boundary
(
    in
    {
      type patch;
      faces ((0 4 7 3));
    }
    out
    {
      type patch;
      faces ((2 6 5 1));
    }
    sxdx
    {
      type cyclic;
      faces ((0 3 2 1) (4 5 6 7));
    }
    topbottom
    {
      type cyclic;
      faces ((1 5 4 0) (3 7 6 2));
    }
);