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Reconstructing undecomposed faceZone in parallel

Hi all,
I have a decomposed case where several faceZones have been split over several processors. I need to reconstruct the original undecomposed faceZone in parallel so that the original face ordering is consistent.
I know that I can used faceProcAddr to map the decomposed faceZone to the undecomposed (global) face Ids, but I'm not sure how to access the undecomposed faceZone list from each processor so that I can reorder the faces correctly.
Do I need to create a dummy objectRegistry to force IOobject to point to the undecomposed mesh directories and read in the undecomposed faceZoneMesh? I really hope there's an easier way than this.
Alternatively I know that OpenFOAM-1.6-ext supports global faceZones when decomposing the mesh but I'm not sure if the ordering of the faces is consistent in this case.

Any suggestions would be appreciated.

Ivor

Quote:

Originally Posted by cliffoi (Post 426383)

Hi Ivor,

just came across this thread and have some thoughts which may be useful:

I use globalFaceZones in OpenFOAM-1.6-ext, so I can create the global face zone field whenever I need it and get the local field back from the global too, here's an example which will make things clearer:

Code:

    // local patch U field

    vectorField localU = U.boundaryField()[patchID];

    

    // put local U into globalU

    const label patchStart

      = mesh.boundaryMesh()[patchID].start();

    vectorField globalU(mesh.faceZones()[faceZoneID].size(), vector::zero);

    forAll(localU, i)

      {

        globalU[mesh.faceZones()[faceZoneID].whichFace(patchStart + i)] =

          localU[i];

      }



    // sync parallel data

    // sum because each face is only on one proc

    reduce(globalU, sumOp<vectorField>()); 



    // now I can do some calculation with globalU

    // DO SOMETHING HERE WITH GLOBALU



    // now put global field back into local

    forAll(localU, i)

      {

        localU[i] =

          globalU

          [

           mesh.faceZones()[faceZoneID].whichFace(patchStart + i)

           ];

      }

Hope it helps,
Philip