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Old   August 12, 2009, 07:56
Default cyclic boundaries
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Hello,

i have little understanding problem with cyclic boundaries. I want to cut a cylinder into 8 pieces. Now i have to define the boundaries in the blockMeshDich file. I think the liner is a wall, the piston is a wall too and the cylinderhead as well. But what boundary conditions needs the "fictive" left an right wall ? Anybody understand what i mean ? If not i can attach a draft
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Old   August 12, 2009, 11:18
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The problem ist that layerAR doenst work with cyclic boundaries. I testet 4 cases an everytime it crashes until layerAR wants to delete a layer.
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Old   August 13, 2009, 05:55
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Ok, either i am annoying everybody with my "dummy" problem or there is really nobody who can help me or there is nobody who can imagine. I attached a simplified draft now.

As u can see I defined the two walls as "cyclic", i think this is pretty standard to use. Stupidly layerAR doenst want to work with these conditons. If i define these two surfaces as a "patch" all is done fine. But i think this would be a problem for solving combustion problems.

Anybody an idea ? Would be very nice
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Old   August 14, 2009, 05:03
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I found out it is a problem in cyclicPolyPatch.C:1253 . In this loop pFaces[i] achieve numbers which cause a segmentation fault. I think it is a bug. I looked in openfoam-1.6 nothing changed at this point. Maybe interesting for jasak ?
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Old   August 17, 2009, 10:17
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New informations:

The label list needs an update before the loop starts.

Code:
if (!matchedAll)
    {
        label baffleI = 0;
      forAll(*this, faceI)
        {
            const face& f = pp.localFaces()[faceI]; 
        //hole faces
            const labelList& pFaces = pp.pointFaces()[f[0]];
 
        Info << "list size= " << size() << endl; // Debug
        //size_(size);
        //return mesh_.nFaces();
        label matchedFaceI = -1;
        forAll(pFaces, i)
            {
 
                label otherFaceI = pFaces[i];
        //Debug
        Info << " pFaces[i] = " << pFaces[i] << " i=" << i << " and faceI= " 
        << faceI << " and otherFaceI= " 
        << otherFaceI  <<  endl;
        // Debug
            if (otherFaceI > faceI)
                {
                    const face& otherF = pp.localFaces()[otherFaceI];
            Info << "otherFaceI = " << otherFaceI;
                    // Note: might pick up two similar oriented faces
                    //       (but that is illegal anyway)
                    if (f == otherF)
                    {
                        matchedFaceI = otherFaceI;
            Info << "matchedFaceI = " <<  matchedFaceI;
                        break;
                    }
                }
            }
 
            if (matchedFaceI != -1)
            {
                half0ToPatch[baffleI] = faceI;
                half1ToPatch[baffleI] = matchedFaceI;
                baffleI++;
            }
        }

size() is the old number of the cylic faces at this point but for a correct loop he needs the the actual label size because after layerAR faces are removed an renumbered! UListI.H gets it with size_ but i didn't find a way to include this actually.
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Old   August 19, 2009, 11:29
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Nobody an idea how to read lists ?
Quote:
const labelList& meshPoints = patch().meshPoints();
I want to look which parameters instead of "meshPoints()" exists.

e.g.

patch().facePoints(); (or something like this)

This would be a great help to debug this (i think simple) problem. But it's hard if u didn't write the code.
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Old   January 11, 2011, 05:23
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Hi dipling,

it has been awhile. But did you had success? I am running into the same problem as you now. Any hint would be helpful!

Best regards,
Georg
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Old   January 11, 2011, 06:30
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You have to debug/patch cyclicpolypatch class. I think there was something weird with a loop, but it was easy to solve. And there was another problem with this class, but i can't remember. I stopped this procedure because there were several problems after fixing those bugs. It theoretically worked but the mass was not constant, so finally I waste too much time for one little step. But I stored those fixes (somewhere).
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