[federicabi]

Hi everyone!

I'm trying to create a mesh with snappyHexMesh in OF 3.0.1 and I need to insert a refinement searchable box rotated around z-axis. So I used searchableSurfaceCollection in this way

/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  2.3.0                                 |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    object      snappyHexMeshDict;
}

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

// Which of the steps to run
castellatedMesh true;
snap            false;
addLayers       false;


// Geometry. Definition of all surfaces. All surfaces are of class
// searchableSurface.
// Surfaces are used
// - to specify refinement for any mesh cell intersecting it
// - to specify refinement for any mesh cell inside/outside/near
// - to 'snap' the mesh boundary to the surface
geometry
{
    scafo.stl
    {
        type triSurfaceMesh;
        name scafo;

        patchInfo
        {
            type wall;
        }
    }

    refinementBox1
    {
        type searchableBox;
        min (-0.4 0 -2.4);
        max (27.2 3.8 4.8);
    }

    refinementBoxI1
    {
        type searchableBox;
        min (0 0 -0.4);
        max (60 5 0.4);  
    }

    refinementBoxS
    {
        type searchableBox;
        min (-10 0 -1.5);
        max (1 5 0.5);
    }
    refinementBoxM
    {
        type searchableSurfaceCollection;
    mergeSubRegions true;
    
    refinementBoxM
    {
      surface box;
      scale (80 24 2);
      transform
      {
        type cartesian;
        origin (0 0 0);
        e1 (0.9847835588179368 -0.17378533390904768 0);
        e3 (0 0 1);
      }
    }
    }
        

};

Unfortunately it doesn't work and OF returns this error

--> FOAM FATAL IO ERROR: 
keyword coordinateSystem is undefined in dictionary "/home/jolly/OpenFOAM/Stage_Federica/AZ95rph/AZ95rph_snappyHexMesh/AZ95rph_snappyHexMesh_Fisso_26kn_1/system/snappyHexMeshDict.geometry.refinementBoxM.refinementBoxM.transform"

file: /home/jolly/OpenFOAM/Stage_Federica/AZ95rph/AZ95rph_snappyHexMesh/AZ95rph_snappyHexMesh_Fisso_26kn_1/system/snappyHexMeshDict.geometry.refinementBoxM.refinementBoxM.transform from line 75 to line 77.

    From function dictionary::subDict(const word& keyword) const
    in file db/dictionary/dictionary.C at line 648.

FOAM exiting

I think that this error can be due to the different OF version of the searchableSurfaceCollection subdictionary, that I found for OF 2.1.x, but I can't find anything for OF 3.0.x.

Can you help me please?

Best regards

Federica

[TobM]

Hi,
a good way to start are the tutorials. Use something like this:
find $FOAM_TUTORIALS -name snappyHexMeshDict | xargs grep coordinateSystem
to search for keywords.
There you will find an example:
tutorials/heatTransfer/buoyantBoussinesqSimpleFoam/iglooWithFridges/system/snappyHexMeshDict

[federicabi]

Hi TobM!
Thank you very much for your quickly reply, I've just found that tutorial and it is exactly what I need.
Thanks for your help!

Best regards

Federica

[federicabi]

I have another question about it. I use the subdictionary found into the tutorial that you have mentioned before and it worked, the box is generated, but when snappy starts the region-wise refinement, it returns me the following error

--> FOAM FATAL ERROR: 
Shell refinementBoxM does not support testing for inside
Probably it is not closed.

    From function shellSurfaces::shellSurfaces(const searchableSurfaces&, const PtrList<dictionary>&)
    in file autoHexMesh/shellSurfaces/shellSurfaces.C at line 134.

FOAM exiting

My question is: how can a box created by snappy be open? it is quite strange to me.
Do you have any suggestion?

[TobM]

Just an idea:
Are your boxes inside your geometry, or are they overlapping?
Does sHM run without this refinement zone?

I haven't worked with this functionality, so I can't help you any futher.

[federicabi]

Actually the box has one vertex outside the mesh, maybe that is the problem, I didn't notice it because of the rotation. Also it overlaps with the other refinement boxes.
Without that box sHM runs without errors.

I'll try to find a solution.
Maybe an stl file that recreate the same geometry of the rotated box could be a way. what do you think?
Thanks a lot for your help.

[TobM]

The overlapping with other refinement boxes shouldn't be a problem.
In a first try, make the box smaller and see if it works.