[RobertoCirolini]

Dear Foamers,

I've been looking for a way to mirror my cellZones. I want to generate a cylinder, however I have just managed to create a veery thin slice of it, if you see the picture below, the red part is my porous medium. The fluid flows from the left to the right and I would like to mirror this slice till I get the full cylinder. However, I realized that when I mirror my mesh the cellZones, in this case porous medium, are not mirrored. Is there somebody who could please give me a hint? I generated the mesh using blockMeshDict and I am trying different ways to obtain this full cylinder with the CellZones, but I am stuck in this part...

Thank you!!!

Roberto

[F42]

Hi Roberto, did you or anybody find a solution to that?
I want to mirror a mesh for a multi region case.

Mirroring the whole mesh works but I cannot run splitMeshRegions to split the mesh into regions because the cellZones are not mirrored.


Thank you, any hints are appreciated.

[GerhardHolzinger]

This is actually quite straight forward: loop over your cells belonging to a set or zone, and find its mirror image.


Here's some code, which has last been used using OpenFOAM 6 and/or 7.


Note that I will not provide any support.

//     mirrorCellSets                             
                           
                            #include "argList.H"                             #include "Time.H"                              
                            #include "volFields.H"                              
                            #include "plane.H"                              
                            #include "topoSetSource.H"                             #include "cellSet.H"                             #include "faceSet.H"                             #include "pointSet.H"                             #include "cellZoneSet.H"                              
                            #include "IOobjectList.H"                             #include "SortableList.H"                              
                            using namespace Foam;                              
                            // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //                              
                            int main(int argc, char *argv[])                             {                                 argList::addBoolOption                                 (                                     "verbose",                                     "be more talkative"                                 );                                 argList::addOption                                 (                                     "dict",                                     "file",                                     "specify alternative dictionary for the mirrorMesh description"                                 );                                 argList::addOption                                 (                                     "excludeSet",                                     "name",                                     "exclude the specified cellSet from mirroring"                                 );                                 
                                #include "setRootCase.H"                                 #include "createTime.H"                                 #include "createMesh.H"                                 
                                const bool verbose = args.optionFound("verbose");                                 
                                
                                
                                const word dictName("mirrorMeshDict");                                 
                                fileName dictPath = dictName;                              
                                // Check if the dictionary is specified on the command-line                                 if (args.optionFound("dict"))                                 {                                     dictPath = args["dict"];                              
                                    dictPath =                                     (                                         isDir(dictPath)                                       ? dictPath/dictName                                       : dictPath                                     );                                 }                                 
                                
                                // read the excludeSetName from command-line                                 word excludeSetName;                                 if (args.optionReadIfPresent("excludeSet", excludeSetName))                                 {                                     Info<< "Excluding " << excludeSetName << " from mirroring." << nl << endl;                                 }                              
                                
                                // read mirrorMeshDict and create mirror plane                                 IOdictionary mirrorMeshDict                                 (                                     IOobject                                     (                                         dictPath,                                         runTime.system(),                                         mesh,                                         IOobject::MUST_READ_IF_MODIFIED,                                         IOobject::NO_WRITE                                     )                                 );                                 
                                
                                plane mirrorPlane(mirrorMeshDict);                                 
                                
                                // get all cell centroid positions                                 const volVectorField& cellCenters(mesh.C());                                 
                                
                                // Process cell sets                                 Info<< "Listing all cell sets." << endl;                                 
                                // Search for list of objects for the time of the mesh                                 word setsInstance = runTime.findInstance                                 (                                     polyMesh::meshSubDir/"sets",                                     word::null,                                     IOobject::MUST_READ,                                     mesh.facesInstance()                                 );                              
                                IOobjectList objects(mesh, setsInstance, polyMesh::meshSubDir/"sets");                                 IOobjectList cellObjects(objects.lookupClass(cellSet::typeName));                                 
                                forAllConstIter(IOobjectList, cellObjects, iter)                                 {                                     // Not in memory. Load it.                                     cellSet set(*iter());                                     SortableList<label> cellLabels(set.toc());                              
                                    label zoneID = mesh.cellZones().findZoneID(set.name());                                     
                                    // skip the excluded set                                     if (set.name() == excludeSetName)                                     {                                         continue;                                     }                                     
                                    if (zoneID == -1)                                     {                                         Info<< nl << "Operating on set " << set.name() << endl;                                     }                                     else                                     {                                         Info<< nl << "Operating on set/zone " << set.name() << endl;                                     }                                     
                                    if (verbose)                                     {                                         Info<< "    " << set.type() << " "                                             << set.name()                                             << " now size "                                             << returnReduce(set.size(), sumOp<label>())                                             << endl;                                     }                                     
                                    
                                    labelList sourceCells(set.size());                                     label nNewCells = 0;                                     
                                    forAll(set.toc(), i)                                     {                                         label cellI = set.toc()[i];                                         
                                        // mirror cell centroid's position and find corresponding cell                                         scalar alpha =                                             mirrorPlane.normalIntersect                                             (                                                 cellCenters.internalField()[cellI],                                                 mirrorPlane.normal()                                             );                                         
                                        label newCellI = mesh.findCell(cellCenters.internalField()[cellI] + 2.0*alpha*mirrorPlane.normal());                                         
                                        
                                        sourceCells[nNewCells] = newCellI;                                         nNewCells++;                                     }                                     
                                    // add found cells to current cellSet                                     dictionary sourceDict01;                                     sourceDict01.name() = "sourceInfo";                                     sourceDict01.set("value", sourceCells);                                     
                                    autoPtr<topoSetSource> sourceCellSet = topoSetSource::New                                     (                                         "labelToCell",                                         static_cast<polyMesh&>(mesh),                                         sourceDict01                                     );                                     
                                    sourceCellSet().applyToSet(topoSetSource::NEW, set);                                     
                                    if (verbose)                                     {                                         Info<< "    " << set.type() << " "                                             << set.name()                                             << " now size "                                             << returnReduce(set.size(), sumOp<label>())                                             << nl << endl;                                     }                                     
                                    set.sync(mesh);                                     set.write();                                     
                                    
                                    // add cells to cellZone                                     if (zoneID > -1)                                     {                                         // read cellZoneSet                                         autoPtr<topoSet> currentZone = topoSet::New                                         (                                             "cellZoneSet",                                             static_cast<polyMesh&>(mesh),                                             set.name()                                         );                                         if (verbose and currentZone.valid())                                         {                                             Info<< "    " << currentZone().type() << " "                                                 << currentZone().name()                                                 << " now size "                                                 << returnReduce(currentZone().size(), sumOp<label>())                                                 << endl;                                         }                                         
                                        // build source topoSet                                         dictionary sourceDict;                                         sourceDict.name() = "sourceInfo";                                         sourceDict.set("set", mesh.cellZones()[zoneID].name());                                         
                                        autoPtr<topoSetSource> source = topoSetSource::New                                         (                                             "setToCellZone",                                             static_cast<polyMesh&>(mesh),                                             sourceDict                                         );                                         
                                        
                                        // add the source to current zone                                         source().applyToSet(topoSetSource::ADD, currentZone());                                         
                                        if (verbose and currentZone.valid())                                         {                                             Info<< "    " << currentZone().type() << " "                                                 << currentZone().name()                                                 << " now size "                                                 << returnReduce(currentZone().size(), sumOp<label>())                                                 << endl;                                         }                                         
                                        currentZone().sync(mesh);                                         currentZone().write();                                     }                                     
                                }                                 
                             
                                Info<< "End\n" << endl;                                 
                                
                                 return 0;
                             }

Somehow, the pretty formatting got lost in copy&paste.

[F42]

Thanks you! Sounds good



I would love to try that.
The code is actually pretty blown up .
Would you mind to append the original file?