ENH: snappy - do not merge patch faces on either side of nelwy created baffles

src/mesh/autoMesh/autoHexMesh/autoHexMeshDriver/autoLayerDriver.C

@@ -2470,12 +2470,15 @@ void Foam::autoLayerDriver::mergePatchFacesUndo
         << "      (0=straight, 180=fully concave)" << nl
         << endl;
 
+    const fvMesh& mesh = meshRefiner_.mesh();
+
     label nChanged = meshRefiner_.mergePatchFacesUndo
     (
         minCos,
         concaveCos,
         meshRefiner_.meshedPatches(),
-        motionDict
+        motionDict,
+        labelList(mesh.nFaces() -1)
     );
 
     nChanged += meshRefiner_.mergeEdgesUndo(minCos, motionDict);

src/mesh/autoMesh/autoHexMesh/autoHexMeshDriver/autoRefineDriver.C

@@ -1079,12 +1079,15 @@ void Foam::autoRefineDriver::mergePatchFaces
         << "----------------------------" << nl
         << endl;
 
+    const fvMesh& mesh = meshRefiner_.mesh();
+
     meshRefiner_.mergePatchFacesUndo
     (
         Foam::cos(degToRad(45.0)),
         Foam::cos(degToRad(45.0)),
         meshRefiner_.meshedPatches(),
-        motionDict
+        motionDict,
+        labelList(mesh.nFaces(), -1)
     );
 
     if (debug)

src/mesh/autoMesh/autoHexMesh/autoHexMeshDriver/autoSnapDriver.C

@@ -1348,7 +1348,8 @@ bool Foam::autoSnapDriver::scaleMesh
 Foam::autoPtr<Foam::mapPolyMesh> Foam::autoSnapDriver::repatchToSurface
 (
     const snapParameters& snapParams,
-    const labelList& adaptPatchIDs
+    const labelList& adaptPatchIDs,
+    const labelList& preserveFaces
 )
 {
     const fvMesh& mesh = meshRefiner_.mesh();
@@ -1375,7 +1376,16 @@ Foam::autoPtr<Foam::mapPolyMesh> Foam::autoSnapDriver::repatchToSurface
     // Faces that do not move
     PackedBoolList isZonedFace(mesh.nFaces());
     {
-        // 1. All faces on zoned surfaces
+        // 1. Preserve faces in preserveFaces list
+        forAll(preserveFaces, faceI)
+        {
+            if (preserveFaces[faceI] != -1)
+            {
+                isZonedFace.set(faceI, 1);
+            }
+        }
+
+        // 2. All faces on zoned surfaces
         const wordList& faceZoneNames = surfaces.faceZoneNames();
         const faceZoneMesh& fZones = mesh.faceZones();
 
@@ -1531,6 +1541,15 @@ void Foam::autoSnapDriver::doSnap
         baffles
     );
 
+    // Keep copy of baffles
+    labelList origBaffles(mesh.nFaces(), -1);
+
+    forAll(baffles, i)
+    {
+        const labelPair& baffle = baffles[i];
+        origBaffles[baffle.first()] = baffle.second();
+        origBaffles[baffle.second()] = baffle.first();
+    }
 
     // Selectively 'forget' about the baffles, i.e. not check across them
     // or merge across them.
@@ -1618,6 +1637,19 @@ void Foam::autoSnapDriver::doSnap
             );
             meshRefinement::updateList(mapPtr().faceMap(), -1, filterFace);
 
+            const labelList& reverseFaceMap = mapPtr().reverseFaceMap();
+            origBaffles.setSize(mesh.nFaces());
+            origBaffles = -1;
+
+            forAll(baffles, i)
+            {
+                labelPair& baffle = baffles[i];
+                baffle.first() = reverseFaceMap[baffle.first()];
+                baffle.second() = reverseFaceMap[baffle.second()];
+                origBaffles[baffle.first()] = baffle.second();
+                origBaffles[baffle.second()] = baffle.first();
+            }
+
             if (debug&meshRefinement::MESH)
             {
                 const_cast<Time&>(mesh.time())++;
@@ -1834,10 +1866,23 @@ void Foam::autoSnapDriver::doSnap
     }
 
     // Merge any introduced baffles.
-    mergeZoneBaffles(baffles);
+    {
+        autoPtr<mapPolyMesh> mapPtr = mergeZoneBaffles(baffles);
+
+        if (mapPtr.valid())
+        {
+            forAll(origBaffles, faceI)
+            {
+                if (origBaffles[faceI] != -1)
+                {
+                    origBaffles[faceI] = mapPtr->reverseFaceMap()[faceI];
+                }
+            }
+        }
+    }
 
     // Repatch faces according to nearest.
-    repatchToSurface(snapParams, adaptPatchIDs);
+    repatchToSurface(snapParams, adaptPatchIDs, origBaffles);
 
     // Repatching might have caused faces to be on same patch and hence
     // mergeable so try again to merge coplanar faces
@@ -1846,7 +1891,8 @@ void Foam::autoSnapDriver::doSnap
         featureCos,  // minCos
         featureCos,  // concaveCos
         meshRefiner_.meshedPatches(),
-        motionDict
+        motionDict,
+        origBaffles
     );
 
     nChanged += meshRefiner_.mergeEdgesUndo
@@ -1855,7 +1901,7 @@ void Foam::autoSnapDriver::doSnap
         motionDict
     );
 
-    if (nChanged > 0 && debug&meshRefinement::MESH)
+    if (nChanged > 0 && debug & meshRefinement::MESH)
     {
         const_cast<Time&>(mesh.time())++;
         Info<< "Writing patchFace merged mesh to time "

src/mesh/autoMesh/autoHexMesh/autoHexMeshDriver/autoSnapDriver.H

@@ -474,7 +474,8 @@ public:
             autoPtr<mapPolyMesh> repatchToSurface
             (
                 const snapParameters& snapParams,
-                const labelList& adaptPatchIDs
+                const labelList& adaptPatchIDs,
+                const labelList& preserveFaces
             );
 
             void doSnap

src/mesh/autoMesh/autoHexMesh/meshRefinement/meshRefinement.H

@@ -920,7 +920,8 @@ public:
                     const scalar minCos,
                     const scalar concaveCos,
                     const labelList& patchIDs,
-                    const dictionary& motionDict
+                    const dictionary& motionDict,
+                    const labelList& preserveFaces
                 );
 
                 autoPtr<mapPolyMesh> doRemovePoints

src/mesh/autoMesh/autoHexMesh/meshRefinement/meshRefinementMerge.C

@@ -249,7 +249,8 @@ Foam::label Foam::meshRefinement::mergePatchFacesUndo
     const scalar minCos,
     const scalar concaveCos,
     const labelList& patchIDs,
-    const dictionary& motionDict
+    const dictionary& motionDict,
+    const labelList& preserveFaces
 )
 {
     // Patch face merging engine
@@ -280,7 +281,7 @@ Foam::label Foam::meshRefinement::mergePatchFacesUndo
     // Get all sets of faces that can be merged. Since only faces on the same
     // patch get merged there is no risk of e.g. patchID faces getting merged
     // with original patches (or even processor patches). There is a risk
-    // though of original patchfaces getting merged if they make a small
+    // though of original patch faces getting merged if they make a small
     // angle. Would be pretty weird starting mesh though.
     labelListList allFaceSets
     (
@@ -292,6 +293,27 @@ Foam::label Foam::meshRefinement::mergePatchFacesUndo
         )
     );
 
+    label compactI = 0;
+    forAll(allFaceSets, i)
+    {
+        bool keep = true;
+        const labelList& set = allFaceSets[i];
+        forAll(set, j)
+        {
+            if (preserveFaces[set[j]] != -1)
+            {
+                keep = false;
+                break;
+            }
+        }
+
+        if (keep && (compactI != i))
+        {
+            allFaceSets[compactI++] = set;
+        }
+    }
+    allFaceSets.setSize(compactI);
+
     label nFaceSets = returnReduce(allFaceSets.size(), sumOp<label>());
 
     Info<< "Merging " << nFaceSets << " sets of faces." << nl << endl;