From ba10afea77783cde36cc8b5db7151de041271f9d Mon Sep 17 00:00:00 2001
From: Mark Olesen <Mark.Olesen@esi-group.com>
Date: Fri, 20 May 2022 11:02:49 +0200
Subject: [PATCH] ENH: add 'filtered' polyMesh regionName() method

- in various situations with mesh regions it is also useful to
  filter out or remove the defaultRegion name (ie, "region0").

  Can now do that conveniently from the polyMesh itself or as a static
  function. Simply use this

      const word& regionDir = polyMesh::regionName(regionName);

  OR  mesh.regionName()

  instead of

      const word& regionDir =
      (
           regionName != polyMesh::defaultRegion
         ? regionName
         : word::null
      );

  Additionally, since the string '/' join operator filters out empty
  strings, the following will work correctly:

      (polyMesh::regionName(regionName)/polyMesh::meshSubDir)

      (mesh.regionName()/polyMesh::meshSubDir)
---
 .../createUpdatedDynamicFvMesh.H              | 60 ++++++++++++-----
 .../createUpdatedDynamicFvMesh.H              | 60 ++++++++++++-----
 .../Test-checkDecomposePar.C                  |  7 +-
 .../makeFaMesh/findMeshDefinitionDict.H       | 12 ++--
 .../mesh/conversion/gmshToFoam/gmshToFoam.C   |  2 +-
 .../generation/PDRblockMesh/PDRblockMesh.C    |  3 +-
 .../PDRblockMesh/cleanMeshDirectory.H         |  5 +-
 .../mesh/generation/blockMesh/blockMesh.C     |  5 +-
 .../generation/blockMesh/cleanMeshDirectory.H |  5 +-
 .../generation/blockMesh/findBlockMeshDict.H  | 13 ++--
 .../extrude/extrudeMesh/extrudeMesh.C         | 15 +++--
 .../extrude2DMesh/extrude2DMeshApp.C          |  6 +-
 .../conformalVoronoiMeshIO.C                  |  2 +-
 .../manipulation/checkMesh/checkGeometry.C    |  6 +-
 .../mesh/manipulation/checkMesh/checkTools.C  | 11 +---
 .../mesh/manipulation/rotateMesh/rotateMesh.C |  7 +-
 .../transformPoints/transformPoints.C         |  5 +-
 .../foamFormatConvert/foamFormatConvert.C     | 23 ++++---
 .../decomposePar/decomposePar.C               |  7 +-
 .../reconstructPar/reconstructPar.C           |  9 +--
 .../reconstructParMesh/reconstructParMesh.C   | 35 ++--------
 .../redistributePar/redistributePar.C         | 11 +---
 .../foamToEnsight/createMeshAccounting.H      |  7 +-
 .../foamToEnsight/findCloudFields.H           | 11 ++--
 .../foamToEnsight/foamToEnsight.C             |  7 +-
 .../dataConversion/foamToVTK/foamToVTK.C      | 23 +++----
 .../changeDictionary/changeDictionary.C       | 11 +---
 .../createZeroDirectory/createZeroDirectory.C |  4 +-
 .../createZeroDirectory/solverTemplate.C      |  9 +--
 .../preProcessing/mapFields/mapFields.C       | 20 +++---
 .../preProcessing/mapFieldsPar/mapFieldsPar.C | 14 ++--
 .../db/functionObjects/writeFile/writeFile.C  | 13 ++--
 src/OpenFOAM/include/createNamedMeshes.H      |  6 +-
 src/OpenFOAM/meshes/polyMesh/polyMesh.C       | 20 +++++-
 src/OpenFOAM/meshes/polyMesh/polyMesh.H       | 15 ++++-
 .../pointHistory/pointHistory.C               |  6 +-
 .../dynamicFvMesh/dynamicFvMeshNew.C          | 40 ++++--------
 .../include/createNamedDynamicFvMesh.H        | 65 +++++++++++++------
 .../simplifiedDynamicFvMesh.C                 |  2 +-
 src/finiteArea/faMesh/faMesh.C                |  6 ++
 src/finiteArea/faMesh/faMesh.H                | 32 +++++----
 .../faMesh/faMeshTools/faMeshTools.C          |  6 +-
 .../fvMesh/fvMeshTools/fvMeshTools.C          |  6 +-
 .../columnFvMesh/columnFvMesh.C               | 16 ++---
 .../columnFvMesh/columnFvMesh.H               |  6 +-
 .../field/streamLine/streamLineBase.C         |  9 +--
 .../hydrostaticPressure/hydrostaticPressure.C |  4 +-
 .../utilities/vtkWrite/vtkWrite.C             |  5 +-
 src/sampling/probes/probes.C                  | 10 +--
 .../sampledSet/sampledSets/sampledSets.C      | 22 ++-----
 50 files changed, 347 insertions(+), 357 deletions(-)

diff --git a/applications/solvers/compressible/rhoSimpleFoam/overRhoSimpleFoam/createUpdatedDynamicFvMesh.H b/applications/solvers/compressible/rhoSimpleFoam/overRhoSimpleFoam/createUpdatedDynamicFvMesh.H
index ea5823cc1c..66d37d170f 100644
--- a/applications/solvers/compressible/rhoSimpleFoam/overRhoSimpleFoam/createUpdatedDynamicFvMesh.H
+++ b/applications/solvers/compressible/rhoSimpleFoam/overRhoSimpleFoam/createUpdatedDynamicFvMesh.H
@@ -1,22 +1,52 @@
-    Info<< "Create dynamic mesh for time = "
-        << runTime.timeName() << nl << endl;
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2017 OpenCFD Ltd.
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
 
-    autoPtr<dynamicFvMesh> meshPtr
+Description
+    Create a dynamicFvMesh, with init()
+
+Required Variables
+    - runTime [Time]
+
+Provided Variables
+    - mesh [dynamicFvMesh], meshPtr
+
+\*---------------------------------------------------------------------------*/
+
+Foam::autoPtr<Foam::dynamicFvMesh> meshPtr;
+
+{
+    Foam::Info << "Create dynamic mesh for time = "
+        << runTime.timeName() << Foam::nl;
+
+    meshPtr = dynamicFvMesh::New
     (
-        dynamicFvMesh::New
+        IOobject
         (
-            IOobject
-            (
-                polyMesh::defaultRegion,
-                runTime.timeName(),
-                runTime,
-                IOobject::MUST_READ
-            )
+            polyMesh::defaultRegion,
+            runTime.timeName(),
+            runTime,
+            IOobject::MUST_READ
         )
     );
+}
 
-    dynamicFvMesh& mesh = meshPtr();
 
-    // Calculate initial mesh-to-mesh mapping. Note that this should be
-    // done under the hood, e.g. as a MeshObject
-    mesh.update();
+dynamicFvMesh& mesh = meshPtr();
+
+// Calculate initial mesh-to-mesh mapping. Note that this should be
+// done under the hood, e.g. as a MeshObject
+mesh.update();
+
+Foam::Info << Foam::endl;
+
+
+// ************************************************************************* //
diff --git a/applications/solvers/incompressible/simpleFoam/overSimpleFoam/createUpdatedDynamicFvMesh.H b/applications/solvers/incompressible/simpleFoam/overSimpleFoam/createUpdatedDynamicFvMesh.H
index ea5823cc1c..66d37d170f 100644
--- a/applications/solvers/incompressible/simpleFoam/overSimpleFoam/createUpdatedDynamicFvMesh.H
+++ b/applications/solvers/incompressible/simpleFoam/overSimpleFoam/createUpdatedDynamicFvMesh.H
@@ -1,22 +1,52 @@
-    Info<< "Create dynamic mesh for time = "
-        << runTime.timeName() << nl << endl;
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2017 OpenCFD Ltd.
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
 
-    autoPtr<dynamicFvMesh> meshPtr
+Description
+    Create a dynamicFvMesh, with init()
+
+Required Variables
+    - runTime [Time]
+
+Provided Variables
+    - mesh [dynamicFvMesh], meshPtr
+
+\*---------------------------------------------------------------------------*/
+
+Foam::autoPtr<Foam::dynamicFvMesh> meshPtr;
+
+{
+    Foam::Info << "Create dynamic mesh for time = "
+        << runTime.timeName() << Foam::nl;
+
+    meshPtr = dynamicFvMesh::New
     (
-        dynamicFvMesh::New
+        IOobject
         (
-            IOobject
-            (
-                polyMesh::defaultRegion,
-                runTime.timeName(),
-                runTime,
-                IOobject::MUST_READ
-            )
+            polyMesh::defaultRegion,
+            runTime.timeName(),
+            runTime,
+            IOobject::MUST_READ
         )
     );
+}
 
-    dynamicFvMesh& mesh = meshPtr();
 
-    // Calculate initial mesh-to-mesh mapping. Note that this should be
-    // done under the hood, e.g. as a MeshObject
-    mesh.update();
+dynamicFvMesh& mesh = meshPtr();
+
+// Calculate initial mesh-to-mesh mapping. Note that this should be
+// done under the hood, e.g. as a MeshObject
+mesh.update();
+
+Foam::Info << Foam::endl;
+
+
+// ************************************************************************* //
diff --git a/applications/test/checkDecomposePar/Test-checkDecomposePar.C b/applications/test/checkDecomposePar/Test-checkDecomposePar.C
index 3987a7d21e..5cc6bb2311 100644
--- a/applications/test/checkDecomposePar/Test-checkDecomposePar.C
+++ b/applications/test/checkDecomposePar/Test-checkDecomposePar.C
@@ -89,12 +89,7 @@ int main(int argc, char *argv[])
     forAll(regionNames, regioni)
     {
         const word& regionName = regionNames[regioni];
-        // const word& regionDir =
-        // (
-        //     regionName != polyMesh::defaultRegion
-        //   ? regionName
-        //   : word::null
-        // );
+        // const word& regionDir = polyMesh::regionName(regionName);
 
         Info<< "\n\nDecomposing mesh " << regionName << nl << endl;
         Info<< "Create mesh..." << flush;
diff --git a/applications/utilities/finiteArea/makeFaMesh/findMeshDefinitionDict.H b/applications/utilities/finiteArea/makeFaMesh/findMeshDefinitionDict.H
index 5385d38f37..a5697ea69e 100644
--- a/applications/utilities/finiteArea/makeFaMesh/findMeshDefinitionDict.H
+++ b/applications/utilities/finiteArea/makeFaMesh/findMeshDefinitionDict.H
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2021 OpenCFD Ltd.
+    Copyright (C) 2021-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
@@ -21,9 +21,7 @@ autoPtr<IOdictionary> meshDictPtr;
 
 {
     fileName dictPath;
-
-    const word& regionDir =
-        (regionName == polyMesh::defaultRegion ? word::null : regionName);
+    const word& regionDir = polyMesh::regionName(regionName);
 
     if (args.readIfPresent("dict", dictPath))
     {
@@ -40,15 +38,17 @@ autoPtr<IOdictionary> meshDictPtr;
         exists
         (
             runTime.path()/runTime.caseConstant()
-            /regionDir/faMesh::meshSubDir/dictName
+          / regionDir/faMesh::meshSubDir/dictName
         )
     )
     {
         // Dictionary present in constant faMesh directory (old-style)
 
         dictPath =
+        (
             runTime.constant()
-            /regionDir/faMesh::meshSubDir/dictName;
+          / regionDir/faMesh::meshSubDir/dictName
+        );
 
         // Warn that constant/faMesh/faMeshDefinition was used
         // instead of system/faMeshDefinition
diff --git a/applications/utilities/mesh/conversion/gmshToFoam/gmshToFoam.C b/applications/utilities/mesh/conversion/gmshToFoam/gmshToFoam.C
index 83685328e7..fec3b4bed8 100644
--- a/applications/utilities/mesh/conversion/gmshToFoam/gmshToFoam.C
+++ b/applications/utilities/mesh/conversion/gmshToFoam/gmshToFoam.C
@@ -1317,7 +1317,7 @@ int main(int argc, char *argv[])
     #include "setRootCase.H"
     #include "createTime.H"
 
-    word regionName = polyMesh::defaultRegion;
+    word regionName(polyMesh::defaultRegion);
 
     if (args.readIfPresent("region", regionName))
     {
diff --git a/applications/utilities/mesh/generation/PDRblockMesh/PDRblockMesh.C b/applications/utilities/mesh/generation/PDRblockMesh/PDRblockMesh.C
index 32d304c6b4..75fbbe7016 100644
--- a/applications/utilities/mesh/generation/PDRblockMesh/PDRblockMesh.C
+++ b/applications/utilities/mesh/generation/PDRblockMesh/PDRblockMesh.C
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2019-2021 OpenCFD Ltd.
+    Copyright (C) 2019-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -130,7 +130,6 @@ int main(int argc, char *argv[])
     const bool noOuterRegion = args.found("no-outer");
 
     const word regionName(polyMesh::defaultRegion);
-    const word regionPath;
 
 
     // Instance for resulting mesh
diff --git a/applications/utilities/mesh/generation/PDRblockMesh/cleanMeshDirectory.H b/applications/utilities/mesh/generation/PDRblockMesh/cleanMeshDirectory.H
index 46f017fb19..9b0d60bebd 100644
--- a/applications/utilities/mesh/generation/PDRblockMesh/cleanMeshDirectory.H
+++ b/applications/utilities/mesh/generation/PDRblockMesh/cleanMeshDirectory.H
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2020 OpenCFD Ltd.
+    Copyright (C) 2020-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
@@ -18,10 +18,11 @@ Description
 {
     // Shadows enclosing parameter (dictName)
     const word blockMeshDictName("blockMeshDict");
+    const word& regionDir = polyMesh::regionName(regionName);
 
     const fileName polyMeshPath
     (
-        runTime.path()/meshInstance/regionPath/polyMesh::meshSubDir
+        runTime.path()/meshInstance/regionDir/polyMesh::meshSubDir
     );
 
     if (exists(polyMeshPath))
diff --git a/applications/utilities/mesh/generation/blockMesh/blockMesh.C b/applications/utilities/mesh/generation/blockMesh/blockMesh.C
index dae940888c..52942def33 100644
--- a/applications/utilities/mesh/generation/blockMesh/blockMesh.C
+++ b/applications/utilities/mesh/generation/blockMesh/blockMesh.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2016-2021 OpenCFD Ltd.
+    Copyright (C) 2016-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -184,16 +184,13 @@ int main(int argc, char *argv[])
     );
 
     word regionName(polyMesh::defaultRegion);
-    word regionPath;
 
     // Check if the region is specified otherwise mesh the default region
     if (args.readIfPresent("region", regionName))
     {
         Info<< nl << "Generating mesh for region " << regionName << endl;
-        regionPath = regionName;
     }
 
-
     // Instance for resulting mesh
     bool useTime = false;
     word meshInstance(runTime.constant());
diff --git a/applications/utilities/mesh/generation/blockMesh/cleanMeshDirectory.H b/applications/utilities/mesh/generation/blockMesh/cleanMeshDirectory.H
index 46f017fb19..9b0d60bebd 100644
--- a/applications/utilities/mesh/generation/blockMesh/cleanMeshDirectory.H
+++ b/applications/utilities/mesh/generation/blockMesh/cleanMeshDirectory.H
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2020 OpenCFD Ltd.
+    Copyright (C) 2020-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
@@ -18,10 +18,11 @@ Description
 {
     // Shadows enclosing parameter (dictName)
     const word blockMeshDictName("blockMeshDict");
+    const word& regionDir = polyMesh::regionName(regionName);
 
     const fileName polyMeshPath
     (
-        runTime.path()/meshInstance/regionPath/polyMesh::meshSubDir
+        runTime.path()/meshInstance/regionDir/polyMesh::meshSubDir
     );
 
     if (exists(polyMeshPath))
diff --git a/applications/utilities/mesh/generation/blockMesh/findBlockMeshDict.H b/applications/utilities/mesh/generation/blockMesh/findBlockMeshDict.H
index 4f81c74ccc..43f4ffecb6 100644
--- a/applications/utilities/mesh/generation/blockMesh/findBlockMeshDict.H
+++ b/applications/utilities/mesh/generation/blockMesh/findBlockMeshDict.H
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2021 OpenCFD Ltd.
+    Copyright (C) 2021-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
@@ -22,6 +22,7 @@ autoPtr<IOdictionary> meshDictPtr;
 
 {
     fileName dictPath;
+    const word& regionDir = polyMesh::regionName(regionName);
 
     if (args.readIfPresent("dict", dictPath))
     {
@@ -37,15 +38,17 @@ autoPtr<IOdictionary> meshDictPtr;
         exists
         (
             runTime.path()/runTime.constant()
-            /regionPath/polyMesh::meshSubDir/dictName
+          / regionDir/polyMesh::meshSubDir/dictName
         )
     )
     {
         // Dictionary present in constant polyMesh directory (old-style)
 
         dictPath =
+        (
             runTime.constant()
-                /regionPath/polyMesh::meshSubDir/dictName;
+          / regionDir/polyMesh::meshSubDir/dictName
+        );
 
 
         // Warn that constant/polyMesh/blockMeshDict was used
@@ -54,14 +57,14 @@ autoPtr<IOdictionary> meshDictPtr;
             << "Using the old blockMeshDict location: "
             << dictPath << nl
             << "    instead of the default location:  "
-            << runTime.system()/regionPath/dictName << nl
+            << runTime.system()/regionDir/dictName << nl
             << endl;
     }
     else
     {
         // Assume dictionary is to be found in the system directory
 
-        dictPath = runTime.system()/regionPath/dictName;
+        dictPath = runTime.system()/regionDir/dictName;
     }
 
     IOobject meshDictIO
diff --git a/applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C b/applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C
index bc5fba6e60..f93e6f03af 100644
--- a/applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C
+++ b/applications/utilities/mesh/generation/extrude/extrudeMesh/extrudeMesh.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2015-2021 OpenCFD Ltd.
+    Copyright (C) 2015-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -256,21 +256,19 @@ int main(int argc, char *argv[])
     #include "createTimeExtruded.H"
 
     // Get optional regionName
-    word regionName;
-    word regionDir;
+    word regionName(polyMesh::defaultRegion);
     if (args.readIfPresent("region", regionName))
     {
-        regionDir = regionName;
         Info<< "Create mesh " << regionName << " for time = "
             << runTimeExtruded.timeName() << nl << endl;
     }
     else
     {
-        regionName = fvMesh::defaultRegion;
         Info<< "Create mesh for time = "
             << runTimeExtruded.timeName() << nl << endl;
     }
 
+
     const IOdictionary dict
     (
         IOobject::selectIO
@@ -755,7 +753,12 @@ int main(int argc, char *argv[])
 
 
         // Create dummy fvSchemes, fvSolution
-        fvMeshTools::createDummyFvMeshFiles(mesh, regionDir, true);
+        fvMeshTools::createDummyFvMeshFiles
+        (
+            mesh,
+            polyMesh::regionName(regionName),
+            true
+        );
 
         // Create actual mesh from polyTopoChange container
         autoPtr<mapPolyMesh> map = meshMod().makeMesh
diff --git a/applications/utilities/mesh/generation/extrude2DMesh/extrude2DMeshApp.C b/applications/utilities/mesh/generation/extrude2DMesh/extrude2DMeshApp.C
index 92d91f25a9..7b235d8c48 100644
--- a/applications/utilities/mesh/generation/extrude2DMesh/extrude2DMeshApp.C
+++ b/applications/utilities/mesh/generation/extrude2DMesh/extrude2DMeshApp.C
@@ -234,12 +234,12 @@ int main(int argc, char *argv[])
     {
         mesh = autoPtr<polyMesh>::New
         (
-            Foam::IOobject
+            IOobject
             (
-                Foam::polyMesh::defaultRegion,
+                polyMesh::defaultRegion,
                 runTimeExtruded.timeName(),
                 runTimeExtruded,
-                Foam::IOobject::MUST_READ
+                IOobject::MUST_READ
             )
         );
     }
diff --git a/applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/conformalVoronoiMesh/conformalVoronoiMeshIO.C b/applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/conformalVoronoiMesh/conformalVoronoiMeshIO.C
index 37c3a3c528..bad6f988a0 100644
--- a/applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/conformalVoronoiMesh/conformalVoronoiMeshIO.C
+++ b/applications/utilities/mesh/generation/foamyMesh/conformalVoronoiMesh/conformalVoronoiMesh/conformalVoronoiMeshIO.C
@@ -331,7 +331,7 @@ void Foam::conformalVoronoiMesh::writeMesh(const fileName& instance)
 //            (
 //                IOobject
 //                (
-//                    Foam::polyMesh::defaultRegion,
+//                    polyMesh::defaultRegion,
 //                    instance,
 //                    runTime_,
 //                    IOobject::MUST_READ
diff --git a/applications/utilities/mesh/manipulation/checkMesh/checkGeometry.C b/applications/utilities/mesh/manipulation/checkMesh/checkGeometry.C
index ce2c8f83ce..482acaaff3 100644
--- a/applications/utilities/mesh/manipulation/checkMesh/checkGeometry.C
+++ b/applications/utilities/mesh/manipulation/checkMesh/checkGeometry.C
@@ -1015,10 +1015,8 @@ Foam::label Foam::checkGeometry
 
         const fileName outputDir
         (
-            mesh.time().globalPath()
-           /functionObject::outputPrefix
-           /(mesh.name() == polyMesh::defaultRegion ? word::null : mesh.name())
-           /"checkMesh"
+            mesh.time().globalPath()/functionObject::outputPrefix
+          / mesh.regionName()/"checkMesh"
         );
 
         forAll(pbm, patchi)
diff --git a/applications/utilities/mesh/manipulation/checkMesh/checkTools.C b/applications/utilities/mesh/manipulation/checkMesh/checkTools.C
index 7e461b37a9..1b29212518 100644
--- a/applications/utilities/mesh/manipulation/checkMesh/checkTools.C
+++ b/applications/utilities/mesh/manipulation/checkMesh/checkTools.C
@@ -52,15 +52,8 @@ License
 
 void Foam::printMeshStats(const polyMesh& mesh, const bool allTopology)
 {
-    if (mesh.name() == Foam::polyMesh::defaultRegion)
-    {
-        Info<< "Mesh stats" << nl;
-    }
-    else
-    {
-        Info<< "Mesh " << mesh.name() << " stats" << nl;
-    }
-    Info<< "    points:           "
+    Info<< "Mesh stats " << mesh.regionName() << nl
+        << "    points:           "
         << returnReduce(mesh.points().size(), sumOp<label>()) << nl;
 
 
diff --git a/applications/utilities/mesh/manipulation/rotateMesh/rotateMesh.C b/applications/utilities/mesh/manipulation/rotateMesh/rotateMesh.C
index 9950dc0e69..d2e53138ea 100644
--- a/applications/utilities/mesh/manipulation/rotateMesh/rotateMesh.C
+++ b/applications/utilities/mesh/manipulation/rotateMesh/rotateMesh.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2019-2021 OpenCFD Ltd.
+    Copyright (C) 2019-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -130,11 +130,10 @@ int main(int argc, char *argv[])
     forAll(regionNames, regioni)
     {
         const word& regionName = regionNames[regioni];
-        const word& regionDir =
+        const fileName meshDir
         (
-            regionName == polyMesh::defaultRegion ? word::null : regionName
+            polyMesh::regionName(regionName)/polyMesh::meshSubDir
         );
-        const fileName meshDir = regionDir/polyMesh::meshSubDir;
 
         if (regionNames.size() > 1)
         {
diff --git a/applications/utilities/mesh/manipulation/transformPoints/transformPoints.C b/applications/utilities/mesh/manipulation/transformPoints/transformPoints.C
index 2fdcf6edd0..dd82546f4e 100644
--- a/applications/utilities/mesh/manipulation/transformPoints/transformPoints.C
+++ b/applications/utilities/mesh/manipulation/transformPoints/transformPoints.C
@@ -369,11 +369,10 @@ int main(int argc, char *argv[])
     forAll(regionNames, regioni)
     {
         const word& regionName = regionNames[regioni];
-        const word& regionDir =
+        const fileName meshDir
         (
-            regionName == polyMesh::defaultRegion ? word::null : regionName
+            polyMesh::regionName(regionName)/polyMesh::meshSubDir
         );
-        const fileName meshDir = regionDir/polyMesh::meshSubDir;
 
         if (regionNames.size() > 1)
         {
diff --git a/applications/utilities/miscellaneous/foamFormatConvert/foamFormatConvert.C b/applications/utilities/miscellaneous/foamFormatConvert/foamFormatConvert.C
index 518e2510c6..44ef3d3f7c 100644
--- a/applications/utilities/miscellaneous/foamFormatConvert/foamFormatConvert.C
+++ b/applications/utilities/miscellaneous/foamFormatConvert/foamFormatConvert.C
@@ -297,16 +297,18 @@ int main(int argc, char *argv[])
     IOobject::fileModificationChecking = IOobject::timeStamp;
 
 
-    fileName meshDir = polyMesh::meshSubDir;
-    fileName regionPrefix = "";
-    word regionName = polyMesh::defaultRegion;
+    word regionName(polyMesh::defaultRegion);
     if (args.readIfPresent("region", regionName))
     {
         Info<< "Using region " << regionName << nl << endl;
-        regionPrefix = regionName;
-        meshDir = regionName/polyMesh::meshSubDir;
     }
 
+    const fileName meshDir
+    (
+        polyMesh::regionName(regionName)/polyMesh::meshSubDir
+    );
+
+
     Foam::instantList timeDirs = Foam::timeSelector::select0(runTime, args);
 
     forAll(timeDirs, timeI)
@@ -349,7 +351,7 @@ int main(int argc, char *argv[])
         writeMeshObject<pointIOField>
         (
             "internalDelaunayVertices",
-            regionPrefix,
+            polyMesh::regionName(regionName),
             runTime
         );
 
@@ -365,7 +367,12 @@ int main(int argc, char *argv[])
         }
 
         // Get list of objects from the database
-        IOobjectList objects(runTime, runTime.timeName(), regionPrefix);
+        IOobjectList objects
+        (
+            runTime,
+            runTime.timeName(),
+            polyMesh::regionName(regionName)
+        );
 
         forAllConstIters(objects, iter)
         {
@@ -417,7 +424,7 @@ int main(int argc, char *argv[])
             fileHandler().filePath
             (
                 runTime.timePath()
-              / regionPrefix
+              / polyMesh::regionName(regionName)
               / cloud::prefix
             )
         );
diff --git a/applications/utilities/parallelProcessing/decomposePar/decomposePar.C b/applications/utilities/parallelProcessing/decomposePar/decomposePar.C
index 7157fa89dd..a2510f3086 100644
--- a/applications/utilities/parallelProcessing/decomposePar/decomposePar.C
+++ b/applications/utilities/parallelProcessing/decomposePar/decomposePar.C
@@ -274,7 +274,7 @@ void decomposeUniform
             // Link with relative paths
             string parentPath = string("..")/"..";
 
-            if (regionDir != word::null)
+            if (!regionDir.empty())
             {
                 parentPath = parentPath/"..";
             }
@@ -479,10 +479,7 @@ int main(int argc, char *argv[])
     forAll(regionNames, regioni)
     {
         const word& regionName = regionNames[regioni];
-        const word& regionDir =
-        (
-            regionName == polyMesh::defaultRegion ? word::null : regionName
-        );
+        const word& regionDir = polyMesh::regionName(regionName);
 
         if (args.dryRun())
         {
diff --git a/applications/utilities/parallelProcessing/reconstructPar/reconstructPar.C b/applications/utilities/parallelProcessing/reconstructPar/reconstructPar.C
index 5ea758d254..4e3968cd33 100644
--- a/applications/utilities/parallelProcessing/reconstructPar/reconstructPar.C
+++ b/applications/utilities/parallelProcessing/reconstructPar/reconstructPar.C
@@ -294,12 +294,7 @@ int main(int argc, char *argv[])
     forAll(regionNames, regioni)
     {
         const word& regionName = regionNames[regioni];
-        const word& regionDir =
-        (
-            regionName != polyMesh::defaultRegion
-          ? regionName
-          : word::null
-        );
+        const word& regionDir = polyMesh::regionName(regionName);
 
         Info<< "\n\nReconstructing fields" << nl
             << "region=" << regionName << nl << endl;
@@ -925,7 +920,7 @@ int main(int argc, char *argv[])
 
             // For the first region of a multi-region case additionally
             // copy the "uniform" directory in the time directory
-            if (regioni == 0 && regionDir != word::null)
+            if (regioni == 0 && !regionDir.empty())
             {
                 fileName uniformDir0
                 (
diff --git a/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C b/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C
index 7679e08ed3..4b57c890dc 100644
--- a/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C
+++ b/applications/utilities/parallelProcessing/reconstructParMesh/reconstructParMesh.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2016-2021 OpenCFD Ltd.
+    Copyright (C) 2016-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -450,18 +450,11 @@ void writeMesh
     const labelListList& cellProcAddressing
 )
 {
-    const word& regionDir =
-    (
-        mesh.name() == polyMesh::defaultRegion
-      ? word::null
-      : mesh.name()
-    );
-
     const fileName outputDir
     (
         mesh.time().path()
       / mesh.time().timeName()
-      / regionDir
+      / mesh.regionName()
       / polyMesh::meshSubDir
     );
 
@@ -489,18 +482,11 @@ void writeMaps
     const labelUList& boundProcAddressing
 )
 {
-    const word& regionDir =
-    (
-        procMesh.name() == polyMesh::defaultRegion
-      ? word::null
-      : procMesh.name()
-    );
-
     const fileName outputDir
     (
         procMesh.time().caseName()
       / procMesh.facesInstance()
-      / regionDir
+      / procMesh.regionName()
       / polyMesh::meshSubDir
     );
 
@@ -775,18 +761,12 @@ int main(int argc, char *argv[])
         forAll(regionNames, regioni)
         {
             const word& regionName = regionNames[regioni];
-            const word& regionDir =
-            (
-                regionName == polyMesh::defaultRegion
-              ? word::null
-              : regionName
-            );
 
             IOobject facesIO
             (
                 "faces",
                 databases[0].timeName(),
-                regionDir/polyMesh::meshSubDir,
+                polyMesh::regionName(regionName)/polyMesh::meshSubDir,
                 databases[0],
                 IOobject::NO_READ,
                 IOobject::NO_WRITE
@@ -817,12 +797,7 @@ int main(int argc, char *argv[])
         forAll(regionNames, regioni)
         {
             const word& regionName = regionNames[regioni];
-            const word& regionDir =
-            (
-                regionName == polyMesh::defaultRegion
-              ? word::null
-              : regionName
-            );
+            const word& regionDir = polyMesh::regionName(regionName);
 
             if (!hasRegionMesh[regioni])
             {
diff --git a/applications/utilities/parallelProcessing/redistributePar/redistributePar.C b/applications/utilities/parallelProcessing/redistributePar/redistributePar.C
index 36643487d6..9010cd6db2 100644
--- a/applications/utilities/parallelProcessing/redistributePar/redistributePar.C
+++ b/applications/utilities/parallelProcessing/redistributePar/redistributePar.C
@@ -1313,10 +1313,7 @@ int main(int argc, char *argv[])
         forAll(regionNames, regioni)
         {
             const word& regionName = regionNames[regioni];
-            const word& regionDir =
-            (
-                regionName == polyMesh::defaultRegion ? word::null : regionName
-            );
+            const word& regionDir = polyMesh::regionName(regionName);
 
             const fileName volMeshSubDir(regionDir/polyMesh::meshSubDir);
             const fileName areaMeshSubDir(regionDir/faMesh::meshSubDir);
@@ -2087,10 +2084,8 @@ int main(int argc, char *argv[])
         forAll(regionNames, regioni)
         {
             const word& regionName = regionNames[regioni];
-            const word& regionDir =
-            (
-                regionName == polyMesh::defaultRegion ? word::null : regionName
-            );
+            const word& regionDir = polyMesh::regionName(regionName);
+
             const fileName volMeshSubDir(regionDir/polyMesh::meshSubDir);
             const fileName areaMeshSubDir(regionDir/faMesh::meshSubDir);
 
diff --git a/applications/utilities/postProcessing/dataConversion/foamToEnsight/createMeshAccounting.H b/applications/utilities/postProcessing/dataConversion/foamToEnsight/createMeshAccounting.H
index 7d33588a56..43c274ebfc 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToEnsight/createMeshAccounting.H
+++ b/applications/utilities/postProcessing/dataConversion/foamToEnsight/createMeshAccounting.H
@@ -28,12 +28,7 @@ PtrList<ensightFaMesh> ensightMeshesFa(regionNames.size());
         const fvMesh& mesh = meshes[regioni];
 
         const word& regionName = regionNames[regioni];
-        const word& regionDir =
-        (
-            regionName != polyMesh::defaultRegion
-          ? regionName
-          : word::null
-        );
+        const word& regionDir = polyMesh::regionName(regionName);
 
         fileName ensCasePath(outputDir);
         word ensCaseName(args.globalCaseName());
diff --git a/applications/utilities/postProcessing/dataConversion/foamToEnsight/findCloudFields.H b/applications/utilities/postProcessing/dataConversion/foamToEnsight/findCloudFields.H
index debff3288a..30adf8ed22 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToEnsight/findCloudFields.H
+++ b/applications/utilities/postProcessing/dataConversion/foamToEnsight/findCloudFields.H
@@ -29,14 +29,11 @@ if (timeDirs.size() && doLagrangian)
         auto& cloudFields = regionCloudFields[regioni];
 
         const word& regionName = regionNames[regioni];
-        const word& regionDir =
-        (
-            regionName != polyMesh::defaultRegion
-          ? regionName
-          : word::null
-        );
 
-        const fileName cloudPrefix(regionDir/cloud::prefix);
+        const fileName cloudPrefix
+        (
+            polyMesh::regionName(regionName)/cloud::prefix
+        );
 
         for (const instant& inst : timeDirs)
         {
diff --git a/applications/utilities/postProcessing/dataConversion/foamToEnsight/foamToEnsight.C b/applications/utilities/postProcessing/dataConversion/foamToEnsight/foamToEnsight.C
index 12b4891c3d..fab7b60eb8 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToEnsight/foamToEnsight.C
+++ b/applications/utilities/postProcessing/dataConversion/foamToEnsight/foamToEnsight.C
@@ -512,12 +512,7 @@ int main(int argc, char *argv[])
         forAll(regionNames, regioni)
         {
             const word& regionName = regionNames[regioni];
-            const word& regionDir =
-            (
-                regionName != polyMesh::defaultRegion
-              ? regionName
-              : word::null
-            );
+            const word& regionDir = polyMesh::regionName(regionName);
 
             if (regionNames.size() > 1)
             {
diff --git a/applications/utilities/postProcessing/dataConversion/foamToVTK/foamToVTK.C b/applications/utilities/postProcessing/dataConversion/foamToVTK/foamToVTK.C
index 9f02a529bc..a14329a0be 100644
--- a/applications/utilities/postProcessing/dataConversion/foamToVTK/foamToVTK.C
+++ b/applications/utilities/postProcessing/dataConversion/foamToVTK/foamToVTK.C
@@ -697,21 +697,16 @@ int main(int argc, char *argv[])
 
         for (const word& regionName : regionNames)
         {
-            const word& regionDir =
-            (
-                regionName == polyMesh::defaultRegion ? word::null : regionName
-            );
+            fileName regionOutDir(outputDir/polyMesh::regionName(regionName));
 
-            fileName regionalDir(outputDir/regionDir);
-
-            if (args.found("overwrite") && Foam::isDir(regionalDir))
+            if (args.found("overwrite") && Foam::isDir(regionOutDir))
             {
                 Info<< "Removing old directory "
-                    << args.relativePath(regionalDir)
+                    << args.relativePath(regionOutDir)
                     << nl << endl;
-                Foam::rmDir(regionalDir);
+                Foam::rmDir(regionOutDir);
             }
-            Foam::mkDir(regionalDir);
+            Foam::mkDir(regionOutDir);
         }
     }
 
@@ -749,11 +744,9 @@ int main(int argc, char *argv[])
         forAll(regionNames, regioni)
         {
             const word& regionName = regionNames[regioni];
-            const word& regionDir =
-            (
-                regionName == polyMesh::defaultRegion ? word::null : regionName
-            );
-            if (regionNames.size() > 1 || !regionDir.empty())
+            const word& regionDir = polyMesh::regionName(regionName);
+
+            if (regionNames.size() > 1)
             {
                 Info<< "region = " << regionName << nl;
             }
diff --git a/applications/utilities/preProcessing/changeDictionary/changeDictionary.C b/applications/utilities/preProcessing/changeDictionary/changeDictionary.C
index 458dc61e8a..b28e45f831 100644
--- a/applications/utilities/preProcessing/changeDictionary/changeDictionary.C
+++ b/applications/utilities/preProcessing/changeDictionary/changeDictionary.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2016 OpenFOAM Foundation
-    Copyright (C) 2016-2021 OpenCFD Ltd.
+    Copyright (C) 2016-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -498,13 +498,6 @@ int main(int argc, char *argv[])
         }
 
 
-        fileName regionPrefix;
-        if (regionName != polyMesh::defaultRegion)
-        {
-            regionPrefix = regionName;
-        }
-
-
         // Make sure we do not use the master-only reading since we read
         // fields (different per processor) as dictionaries.
         IOobject::fileModificationChecking = IOobject::timeStamp;
@@ -547,7 +540,7 @@ int main(int argc, char *argv[])
                 "boundary",
                 runTime.findInstance
                 (
-                    regionPrefix/polyMesh::meshSubDir,
+                    polyMesh::regionName(regionName)/polyMesh::meshSubDir,
                     "boundary",
                     IOobject::READ_IF_PRESENT
                 ),
diff --git a/applications/utilities/preProcessing/createZeroDirectory/createZeroDirectory.C b/applications/utilities/preProcessing/createZeroDirectory/createZeroDirectory.C
index 5c09e1bbd6..3cdc15bff7 100644
--- a/applications/utilities/preProcessing/createZeroDirectory/createZeroDirectory.C
+++ b/applications/utilities/preProcessing/createZeroDirectory/createZeroDirectory.C
@@ -145,7 +145,7 @@ void createFieldFiles
 
         fileName regionPath = "/";
 
-        if (regionName != word::null)
+        if (!regionName.empty())
         {
             regionPath += regionName + '/';
         }
@@ -294,7 +294,7 @@ int main(int argc, char *argv[])
     {
         const word& regionName = solver.regionName(regionI);
 
-        if (regionName == word::null)
+        if (regionName.empty())
         {
             Info<< "Region: " << polyMesh::defaultRegion << " (default)"
                 << endl;
diff --git a/applications/utilities/preProcessing/createZeroDirectory/solverTemplate.C b/applications/utilities/preProcessing/createZeroDirectory/solverTemplate.C
index aa1a5cf9bc..deeaec6382 100644
--- a/applications/utilities/preProcessing/createZeroDirectory/solverTemplate.C
+++ b/applications/utilities/preProcessing/createZeroDirectory/solverTemplate.C
@@ -78,14 +78,11 @@ Foam::dictionary Foam::solverTemplate::readFluidFieldTemplates
 {
     Info<< "    Reading fluid field templates";
 
-    if (regionName == word::null)
+    if (!regionName.empty())
     {
-        Info<< endl;
-    }
-    else
-    {
-        Info<< " for region " << regionName << endl;
+        Info<< " for region " << regionName;
     }
+    Info<< endl;
 
     dictionary fieldTemplates = solverDict.subDict("fluidFields");
 
diff --git a/applications/utilities/preProcessing/mapFields/mapFields.C b/applications/utilities/preProcessing/mapFields/mapFields.C
index 047e613209..8b5b24dd29 100644
--- a/applications/utilities/preProcessing/mapFields/mapFields.C
+++ b/applications/utilities/preProcessing/mapFields/mapFields.C
@@ -290,21 +290,21 @@ int main(int argc, char *argv[])
     const fileName rootDirSource = casePath.path().toAbsolute();
     const fileName caseDirSource = casePath.name();
 
-    Info<< "Source: " << rootDirSource << " " << caseDirSource << endl;
-    word sourceRegion = polyMesh::defaultRegion;
-    if (args.found("sourceRegion"))
+    Info<< "Source: " << rootDirSource << ' ' << caseDirSource;
+    word sourceRegion(polyMesh::defaultRegion);
+    if (args.readIfPresent("sourceRegion", sourceRegion))
     {
-        sourceRegion = args["sourceRegion"];
-        Info<< "Source region: " << sourceRegion << endl;
+        Info<< " (region " << sourceRegion << ')';
     }
+    Info<< endl;
 
-    Info<< "Target: " << rootDirTarget << " " << caseDirTarget << endl;
-    word targetRegion = polyMesh::defaultRegion;
-    if (args.found("targetRegion"))
+    Info<< "Target: " << rootDirTarget << ' ' << caseDirTarget;
+    word targetRegion(polyMesh::defaultRegion);
+    if (args.readIfPresent("targetRegion", targetRegion))
     {
-        targetRegion = args["targetRegion"];
-        Info<< "Target region: " << targetRegion << endl;
+        Info<< " (region " << targetRegion << ')';
     }
+    Info<< endl;
 
     const bool parallelSource = args.found("parallelSource");
     const bool parallelTarget = args.found("parallelTarget");
diff --git a/applications/utilities/preProcessing/mapFieldsPar/mapFieldsPar.C b/applications/utilities/preProcessing/mapFieldsPar/mapFieldsPar.C
index 8b494325f2..cb610d4549 100644
--- a/applications/utilities/preProcessing/mapFieldsPar/mapFieldsPar.C
+++ b/applications/utilities/preProcessing/mapFieldsPar/mapFieldsPar.C
@@ -220,19 +220,21 @@ int main(int argc, char *argv[])
     const fileName rootDirSource = casePath.path();
     const fileName caseDirSource = casePath.name();
 
-    Info<< "Source: " << rootDirSource << " " << caseDirSource << endl;
-    word sourceRegion = polyMesh::defaultRegion;
+    Info<< "Source: " << rootDirSource << ' ' << caseDirSource;
+    word sourceRegion(polyMesh::defaultRegion);
     if (args.readIfPresent("sourceRegion", sourceRegion))
     {
-        Info<< "Source region: " << sourceRegion << endl;
+        Info<< " (region " << sourceRegion << ')';
     }
+    Info<< endl;
 
-    Info<< "Target: " << rootDirTarget << " " << caseDirTarget << endl;
-    word targetRegion = polyMesh::defaultRegion;
+    Info<< "Target: " << rootDirTarget << ' ' << caseDirTarget;
+    word targetRegion(polyMesh::defaultRegion);
     if (args.readIfPresent("targetRegion", targetRegion))
     {
-        Info<< "Target region: " << targetRegion << endl;
+        Info<< " (region " << targetRegion << ')';
     }
+    Info<< endl;
 
     const bool consistent = args.found("consistent");
 
diff --git a/src/OpenFOAM/db/functionObjects/writeFile/writeFile.C b/src/OpenFOAM/db/functionObjects/writeFile/writeFile.C
index 51be217fda..8c2d9f2cc4 100644
--- a/src/OpenFOAM/db/functionObjects/writeFile/writeFile.C
+++ b/src/OpenFOAM/db/functionObjects/writeFile/writeFile.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2012-2018 OpenFOAM Foundation
-    Copyright (C) 2015-2020 OpenCFD Ltd.
+    Copyright (C) 2015-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -58,14 +58,11 @@ Foam::fileName Foam::functionObjects::writeFile::baseFileDir() const
       / functionObject::outputPrefix
     );
 
-    // Append mesh name if not default region
-    if (isA<polyMesh>(fileObr_))
+    // Append mesh region name if not default region
+    const auto* meshPtr = isA<polyMesh>(fileObr_);
+    if (meshPtr)
     {
-        const polyMesh& mesh = refCast<const polyMesh>(fileObr_);
-        if (mesh.name() != polyMesh::defaultRegion)
-        {
-            baseDir /= mesh.name();
-        }
+        baseDir /= meshPtr->regionName();
     }
     baseDir.clean();  // Remove unneeded ".."
 
diff --git a/src/OpenFOAM/include/createNamedMeshes.H b/src/OpenFOAM/include/createNamedMeshes.H
index a1d1512939..64af72a3de 100644
--- a/src/OpenFOAM/include/createNamedMeshes.H
+++ b/src/OpenFOAM/include/createNamedMeshes.H
@@ -34,11 +34,7 @@ Foam::PtrList<Foam::fvMesh> meshes(regionNames.size());
         const Foam::word& regionName = regionNames[regioni];
 
         Foam::Info<< "Create mesh";
-        if
-        (
-            regionNames.size() > 1
-         || regionName != Foam::polyMesh::defaultRegion
-        )
+        if (regionNames.size() > 1)
         {
             Foam::Info<< ' ' << regionName;
         }
diff --git a/src/OpenFOAM/meshes/polyMesh/polyMesh.C b/src/OpenFOAM/meshes/polyMesh/polyMesh.C
index 466c82fde1..f7fb0e115c 100644
--- a/src/OpenFOAM/meshes/polyMesh/polyMesh.C
+++ b/src/OpenFOAM/meshes/polyMesh/polyMesh.C
@@ -44,11 +44,11 @@ License
 namespace Foam
 {
     defineTypeNameAndDebug(polyMesh, 0);
-
-    word polyMesh::defaultRegion = "region0";
-    word polyMesh::meshSubDir = "polyMesh";
 }
 
+Foam::word Foam::polyMesh::defaultRegion = "region0";
+Foam::word Foam::polyMesh::meshSubDir = "polyMesh";
+
 
 // * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
 
@@ -824,6 +824,14 @@ Foam::polyMesh::~polyMesh()
 }
 
 
+// * * * * * * * * * * * * * Static Member Functions * * * * * * * * * * * * //
+
+const Foam::word& Foam::polyMesh::regionName(const word& region)
+{
+    return (region == polyMesh::defaultRegion ? word::null : region);
+}
+
+
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 const Foam::fileName& Foam::polyMesh::dbDir() const
@@ -843,6 +851,12 @@ Foam::fileName Foam::polyMesh::meshDir() const
 }
 
 
+const Foam::word& Foam::polyMesh::regionName() const
+{
+    return polyMesh::regionName(objectRegistry::name());
+}
+
+
 const Foam::fileName& Foam::polyMesh::pointsInstance() const
 {
     return points_.instance();
diff --git a/src/OpenFOAM/meshes/polyMesh/polyMesh.H b/src/OpenFOAM/meshes/polyMesh/polyMesh.H
index b5512d75fb..f0cdcf83c9 100644
--- a/src/OpenFOAM/meshes/polyMesh/polyMesh.H
+++ b/src/OpenFOAM/meshes/polyMesh/polyMesh.H
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017, 2020 OpenFOAM Foundation
-    Copyright (C) 2018-2021 OpenCFD Ltd.
+    Copyright (C) 2018-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -41,8 +41,8 @@ SourceFiles
 
 \*---------------------------------------------------------------------------*/
 
-#ifndef polyMesh_H
-#define polyMesh_H
+#ifndef Foam_polyMesh_H
+#define Foam_polyMesh_H
 
 #include "objectRegistry.H"
 #include "primitiveMesh.H"
@@ -418,6 +418,15 @@ public:
             );
 
 
+        // Regions
+
+            //- The mesh region name or word::null if polyMesh::defaultRegion
+            static const word& regionName(const word& region);
+
+            //- The mesh region name or word::null if polyMesh::defaultRegion
+            const word& regionName() const;
+
+
         // Access
 
             //- Return raw points
diff --git a/src/dynamicFaMesh/interfaceTrackingFvMesh/functionObjects/pointHistory/pointHistory.C b/src/dynamicFaMesh/interfaceTrackingFvMesh/functionObjects/pointHistory/pointHistory.C
index d1060b286f..4cb7288cc6 100644
--- a/src/dynamicFaMesh/interfaceTrackingFvMesh/functionObjects/pointHistory/pointHistory.C
+++ b/src/dynamicFaMesh/interfaceTrackingFvMesh/functionObjects/pointHistory/pointHistory.C
@@ -48,8 +48,7 @@ namespace Foam
 
 bool Foam::pointHistory::writeData()
 {
-    const fvMesh& mesh =
-        time_.lookupObject<fvMesh>(polyMesh::defaultRegion);
+    const fvMesh& mesh = time_.lookupObject<fvMesh>(polyMesh::defaultRegion);
 
     vector position(Zero);
 
@@ -98,8 +97,7 @@ Foam::pointHistory::pointHistory
     dict.readIfPresent("region", regionName_);
     dict.readIfPresent("historyPointID", historyPointID_);
 
-    const fvMesh& mesh =
-        time_.lookupObject<fvMesh>(regionName_);
+    const fvMesh& mesh = time_.lookupObject<fvMesh>(regionName_);
 
     const vectorField& points = mesh.points();
 
diff --git a/src/dynamicFvMesh/dynamicFvMesh/dynamicFvMeshNew.C b/src/dynamicFvMesh/dynamicFvMesh/dynamicFvMeshNew.C
index ea6a5d9a02..3564381129 100644
--- a/src/dynamicFvMesh/dynamicFvMesh/dynamicFvMeshNew.C
+++ b/src/dynamicFvMesh/dynamicFvMesh/dynamicFvMeshNew.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2019-2021 OpenCFD Ltd.
+    Copyright (C) 2019-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -43,7 +43,7 @@ Foam::autoPtr<Foam::dynamicFvMesh> Foam::dynamicFvMesh::New(const IOobject& io)
     (
         "dynamicMeshDict",
         io.time().constant(),
-        (io.name() == polyMesh::defaultRegion ? "" : io.name()),
+        polyMesh::regionName(io.name()),
         io.db(),
         IOobject::MUST_READ_IF_MODIFIED,
         IOobject::NO_WRITE,
@@ -124,6 +124,14 @@ Foam::autoPtr<Foam::dynamicFvMesh> Foam::dynamicFvMesh::New
     const Time& runTime
 )
 {
+    const IOobject meshIO
+    (
+        polyMesh::defaultRegion,
+        runTime.timeName(),
+        runTime,
+        IOobject::MUST_READ
+    );
+
     if (args.dryRun() || args.found("dry-run-write"))
     {
         Info
@@ -148,32 +156,10 @@ Foam::autoPtr<Foam::dynamicFvMesh> Foam::dynamicFvMesh::New
 
         functionObject::outputPrefix = "postProcessing-dry-run";
 
-        return
-            simplifiedMeshes::simplifiedDynamicFvMeshBase::New
-            (
-                IOobject
-                (
-                    polyMesh::defaultRegion,
-                    runTime.timeName(),
-                    runTime,
-                    IOobject::MUST_READ
-                )
-            );
-    }
-    else
-    {
-        return
-            New
-            (
-                IOobject
-                (
-                    polyMesh::defaultRegion,
-                    runTime.timeName(),
-                    runTime,
-                    IOobject::MUST_READ
-                )
-            );
+        return simplifiedMeshes::simplifiedDynamicFvMeshBase::New(meshIO);
     }
+
+    return New(meshIO);
 }
 
 
diff --git a/src/dynamicFvMesh/include/createNamedDynamicFvMesh.H b/src/dynamicFvMesh/include/createNamedDynamicFvMesh.H
index 6cb1444055..dd659f2481 100644
--- a/src/dynamicFvMesh/include/createNamedDynamicFvMesh.H
+++ b/src/dynamicFvMesh/include/createNamedDynamicFvMesh.H
@@ -1,30 +1,55 @@
-    Foam::word regionName = Foam::polyMesh::defaultRegion;
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2012 OpenFOAM Foundation
+    Copyright (C) 2022 OpenCFD Ltd.
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM, distributed under GPL-3.0-or-later.
 
+Description
+    Create a dynamicFvMesh for a specified region, or the defaultRegion
+
+Required Variables
+    - runTime [Time]
+
+Provided Variables
+    - regionName [word]
+    - mesh [dynamicFvMesh], meshPtr
+
+\*---------------------------------------------------------------------------*/
+
+Foam::word regionName(Foam::polyMesh::defaultRegion);
+Foam::autoPtr<Foam::dynamicFvMesh> meshPtr;
+
+{
+    Foam::Info << "Create dynamic mesh";
     if (args.readIfPresent("region", regionName))
     {
-        Foam::Info
-            << "Create mesh " << regionName << " for time = "
-            << runTime.timeName() << Foam::nl << Foam::endl;
-    }
-    else
-    {
-        Foam::Info
-            << "Create mesh for time = "
-            << runTime.timeName() << Foam::nl << Foam::endl;
+        Foam::Info << ' ' << regionName;
     }
+    Foam::Info << " for time = " << runTime.timeName() << Foam::nl;
 
-    autoPtr<dynamicFvMesh> meshPtr
+    meshPtr = dynamicFvMesh::New
     (
-        dynamicFvMesh::New
+        IOobject
         (
-            IOobject
-            (
-                regionName,
-                runTime.timeName(),
-                runTime,
-                IOobject::MUST_READ
-            )
+            regionName,
+            runTime.timeName(),
+            runTime,
+            IOobject::MUST_READ
         )
     );
+}
 
-    dynamicFvMesh& mesh = meshPtr();
+
+dynamicFvMesh& mesh = meshPtr();
+
+Foam::Info << Foam::endl;
+
+
+// ************************************************************************* //
diff --git a/src/dynamicFvMesh/simplifiedDynamicFvMesh/simplifiedDynamicFvMesh.C b/src/dynamicFvMesh/simplifiedDynamicFvMesh/simplifiedDynamicFvMesh.C
index 92403dedf1..c7db30f8af 100644
--- a/src/dynamicFvMesh/simplifiedDynamicFvMesh/simplifiedDynamicFvMesh.C
+++ b/src/dynamicFvMesh/simplifiedDynamicFvMesh/simplifiedDynamicFvMesh.C
@@ -51,7 +51,7 @@ Foam::simplifiedMeshes::simplifiedDynamicFvMeshBase::New
     (
         "dynamicMeshDict",
         io.time().constant(),
-        (io.name() == polyMesh::defaultRegion ? "" : io.name()),
+        polyMesh::regionName(io.name()),
         io.db(),
         IOobject::MUST_READ_IF_MODIFIED,
         IOobject::NO_WRITE,
diff --git a/src/finiteArea/faMesh/faMesh.C b/src/finiteArea/faMesh/faMesh.C
index 32de35d34a..eeda85f1d5 100644
--- a/src/finiteArea/faMesh/faMesh.C
+++ b/src/finiteArea/faMesh/faMesh.C
@@ -601,6 +601,12 @@ const Foam::objectRegistry& Foam::faMesh::thisDb() const
 }
 
 
+const Foam::word& Foam::faMesh::regionName() const
+{
+    return polyMesh::regionName(thisDb().name());
+}
+
+
 void Foam::faMesh::removeFiles(const fileName& instanceDir) const
 {
     fileName meshFilesPath = thisDb().time().path()/instanceDir/meshDir();
diff --git a/src/finiteArea/faMesh/faMesh.H b/src/finiteArea/faMesh/faMesh.H
index 4d59b4ac79..633ecd56fc 100644
--- a/src/finiteArea/faMesh/faMesh.H
+++ b/src/finiteArea/faMesh/faMesh.H
@@ -665,21 +665,27 @@ public:
         inline bool hasInternalEdgeLabels() const noexcept;
 
 
+    // Database
+
+        //- Return true if thisDb() is a valid DB
+        virtual bool hasDb() const;
+
+        //- Return reference to the mesh database
+        virtual const objectRegistry& thisDb() const;
+
+        //- Name function is needed to disambiguate those inherited
+        //- from base classes
+        const word& name() const
+        {
+            return thisDb().name();
+        }
+
+        //- The mesh region name or word::null if polyMesh::defaultRegion
+        const word& regionName() const;
+
+
         // Access
 
-            //- Return true if thisDb() is a valid DB
-            virtual bool hasDb() const;
-
-            //- Return reference to the mesh database
-            virtual const objectRegistry& thisDb() const;
-
-            //- Name function is needed to disambiguate those inherited
-            //- from base classes
-            const word& name() const
-            {
-                return thisDb().name();
-            }
-
             //- Return constant reference to boundary mesh
             inline const faBoundaryMesh& boundary() const noexcept;
 
diff --git a/src/finiteArea/faMesh/faMeshTools/faMeshTools.C b/src/finiteArea/faMesh/faMeshTools/faMeshTools.C
index 24b46edf5e..b7bbf8b90d 100644
--- a/src/finiteArea/faMesh/faMeshTools/faMeshTools.C
+++ b/src/finiteArea/faMesh/faMeshTools/faMeshTools.C
@@ -77,8 +77,7 @@ Foam::autoPtr<Foam::faMesh> Foam::faMeshTools::newMesh
 
     const fileName meshSubDir
     (
-        (pMesh.name() == polyMesh::defaultRegion ? word::null : pMesh.name())
-      / faMesh::meshSubDir
+        pMesh.regionName() / faMesh::meshSubDir
     );
 
 
@@ -260,8 +259,7 @@ Foam::autoPtr<Foam::faMesh> Foam::faMeshTools::loadOrCreateMesh
 
     const fileName meshSubDir
     (
-        (pMesh.name() == polyMesh::defaultRegion ? word::null : pMesh.name())
-      / faMesh::meshSubDir
+        pMesh.regionName() / faMesh::meshSubDir
     );
 
 
diff --git a/src/finiteVolume/fvMesh/fvMeshTools/fvMeshTools.C b/src/finiteVolume/fvMesh/fvMeshTools/fvMeshTools.C
index 719aea05fd..565c8a9223 100644
--- a/src/finiteVolume/fvMesh/fvMeshTools/fvMeshTools.C
+++ b/src/finiteVolume/fvMesh/fvMeshTools/fvMeshTools.C
@@ -459,8 +459,7 @@ Foam::fvMeshTools::newMesh
 
     const fileName meshSubDir
     (
-        (io.name() == polyMesh::defaultRegion ? word::null : io.name())
-      / polyMesh::meshSubDir
+        polyMesh::regionName(io.name()) / polyMesh::meshSubDir
     );
 
 
@@ -744,8 +743,7 @@ Foam::fvMeshTools::loadOrCreateMesh
 
     const fileName meshSubDir
     (
-        (io.name() == polyMesh::defaultRegion ? word::null : io.name())
-      / polyMesh::meshSubDir
+        polyMesh::regionName(io.name()) / polyMesh::meshSubDir
     );
 
 
diff --git a/src/finiteVolume/fvMesh/simplifiedFvMesh/columnFvMesh/columnFvMesh.C b/src/finiteVolume/fvMesh/simplifiedFvMesh/columnFvMesh/columnFvMesh.C
index c373ab314b..7a242f9525 100644
--- a/src/finiteVolume/fvMesh/simplifiedFvMesh/columnFvMesh/columnFvMesh.C
+++ b/src/finiteVolume/fvMesh/simplifiedFvMesh/columnFvMesh/columnFvMesh.C
@@ -5,7 +5,7 @@
     \\  /    A nd           | www.openfoam.com
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
-    Copyright (C) 2018-2021 OpenCFD Ltd.
+    Copyright (C) 2018-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -64,7 +64,7 @@ bool Foam::simplifiedMeshes::columnFvMeshInfo::setPatchEntries
     (
         "boundary",
         localInstance_,
-        regionPrefix_ + polyMesh::meshSubDir,
+        polyMesh::regionName(regionName_)/polyMesh::meshSubDir,
         runTime,
         IOobject::MUST_READ,
         IOobject::NO_WRITE,
@@ -103,7 +103,7 @@ bool Foam::simplifiedMeshes::columnFvMeshInfo::setPatchEntries
         (
             runTime,
             runTime.timeName(),
-            (regionName_ == polyMesh::defaultRegion ? "" : regionName_)
+            polyMesh::regionName(regionName_)
         );
 
         if (objects.empty())
@@ -209,7 +209,7 @@ void Foam::simplifiedMeshes::columnFvMeshInfo::initialise(const Time& runTime)
         (
             "points",
             localInstance_,
-            regionPrefix_ + polyMesh::meshSubDir,
+            polyMesh::regionName(regionName_)/polyMesh::meshSubDir,
             runTime,
             IOobject::MUST_READ,
             IOobject::NO_WRITE,
@@ -409,17 +409,11 @@ Foam::simplifiedMeshes::columnFvMeshInfo::columnFvMeshInfo
 )
 :
     regionName_(regionName),
-    regionPrefix_
-    (
-        regionName_ == polyMesh::defaultRegion
-      ? ""
-      : regionName_ + '/'
-    ),
     localInstance_
     (
         runTime.findInstance
         (
-            regionPrefix_ + polyMesh::meshSubDir,
+            polyMesh::regionName(regionName_)/polyMesh::meshSubDir,
             "boundary",
             IOobject::READ_IF_PRESENT
         )
diff --git a/src/finiteVolume/fvMesh/simplifiedFvMesh/columnFvMesh/columnFvMesh.H b/src/finiteVolume/fvMesh/simplifiedFvMesh/columnFvMesh/columnFvMesh.H
index 4e345ac3ac..6096bca444 100644
--- a/src/finiteVolume/fvMesh/simplifiedFvMesh/columnFvMesh/columnFvMesh.H
+++ b/src/finiteVolume/fvMesh/simplifiedFvMesh/columnFvMesh/columnFvMesh.H
@@ -73,14 +73,11 @@ class columnFvMeshInfo
 
 protected:
 
-    // Protected data
+    // Protected Data
 
         //- Region of existing mesh
         const word regionName_;
 
-        //- Additional prefix for region. Empty if default region
-        const fileName regionPrefix_;
-
         //- Location of existing mesh (if present)
         const word localInstance_;
 
@@ -111,6 +108,7 @@ protected:
             //- Number of patches with at least 1 local face
             label nPatchWithFace_;
 
+
     // Protected Member Functions
 
         //- Add the patches to the mesh
diff --git a/src/functionObjects/field/streamLine/streamLineBase.C b/src/functionObjects/field/streamLine/streamLineBase.C
index 67cf07f6fa..2540476981 100644
--- a/src/functionObjects/field/streamLine/streamLineBase.C
+++ b/src/functionObjects/field/streamLine/streamLineBase.C
@@ -661,13 +661,10 @@ bool Foam::functionObjects::streamLineBase::writeToFile()
 
         fileName vtkPath
         (
-            time_.globalPath()/functionObject::outputPrefix/"sets"/name()
+            time_.globalPath()/functionObject::outputPrefix/"sets"
+          / name()/mesh_.regionName()
+          / mesh_.time().timeName()
         );
-        if (mesh_.name() != polyMesh::defaultRegion)
-        {
-            vtkPath = vtkPath/mesh_.name();
-        }
-        vtkPath = vtkPath/mesh_.time().timeName();
 
         mkDir(vtkPath);
 
diff --git a/src/functionObjects/initialisation/hydrostaticPressure/hydrostaticPressure.C b/src/functionObjects/initialisation/hydrostaticPressure/hydrostaticPressure.C
index 2edb8e74a2..53b3870081 100644
--- a/src/functionObjects/initialisation/hydrostaticPressure/hydrostaticPressure.C
+++ b/src/functionObjects/initialisation/hydrostaticPressure/hydrostaticPressure.C
@@ -87,9 +87,9 @@ void Foam::functionObjects::hydrostaticPressure::calculateAndWrite()
     auto& p = thermo.p();
 
     Info<< "Performing hydrostatic pressure initialisation";
-    if (mesh_.name() != polyMesh::defaultRegion)
+    if (!mesh_.regionName().empty())
     {
-        Info<< "for region " << mesh_.name();
+        Info<< " region=" << mesh_.name();
     }
 
 
diff --git a/src/functionObjects/utilities/vtkWrite/vtkWrite.C b/src/functionObjects/utilities/vtkWrite/vtkWrite.C
index 5f92c2a7cd..84e49ab664 100644
--- a/src/functionObjects/utilities/vtkWrite/vtkWrite.C
+++ b/src/functionObjects/utilities/vtkWrite/vtkWrite.C
@@ -280,10 +280,7 @@ bool Foam::functionObjects::vtkWrite::write()
     label regioni = 0;
     for (const word& regionName : meshes_.sortedToc())
     {
-        const word& regionDir =
-        (
-            regionName == polyMesh::defaultRegion ? word::null : regionName
-        );
+        const word& regionDir = polyMesh::regionName(regionName);
 
         auto& meshProxy = meshSubsets_[regioni];
         auto& vtuMeshCells = vtuMappings_[regioni];
diff --git a/src/sampling/probes/probes.C b/src/sampling/probes/probes.C
index 849803e57a..bf2e91f9e6 100644
--- a/src/sampling/probes/probes.C
+++ b/src/sampling/probes/probes.C
@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2015-2021 OpenCFD Ltd.
+    Copyright (C) 2015-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -76,17 +76,11 @@ void Foam::probes::createProbeFiles(const wordList& fieldNames)
         // Put in undecomposed case
         // (Note: gives problems for distributed data running)
 
-        fileName probeSubDir = name();
-        if (mesh_.name() != polyMesh::defaultRegion)
-        {
-            probeSubDir = probeSubDir/mesh_.name();
-        }
-
         fileName probeDir
         (
             mesh_.time().globalPath()
           / functionObject::outputPrefix
-          / probeSubDir
+          / name()/mesh_.regionName()
             // Use startTime as the instance for output files
           / mesh_.time().timeName(mesh_.time().startTime().value())
         );
diff --git a/src/sampling/sampledSet/sampledSets/sampledSets.C b/src/sampling/sampledSet/sampledSets/sampledSets.C
index 22a103472d..63248a47ae 100644
--- a/src/sampling/sampledSet/sampledSets/sampledSets.C
+++ b/src/sampling/sampledSet/sampledSets/sampledSets.C
@@ -88,17 +88,11 @@ Foam::OFstream* Foam::sampledSets::createProbeFile(const word& fieldName)
         // Put in undecomposed case
         // (Note: gives problems for distributed data running)
 
-        fileName probeSubDir = name();
-        if (mesh_.name() != polyMesh::defaultRegion)
-        {
-            probeSubDir = probeSubDir/mesh_.name();
-        }
-
         fileName probeDir
         (
             mesh_.time().globalPath()
           / functionObject::outputPrefix
-          / probeSubDir
+          / name()/mesh_.regionName()
             // Use startTime as the instance for output files
           / mesh_.time().timeName(mesh_.time().startTime().value())
         );
@@ -446,7 +440,8 @@ Foam::sampledSets::sampledSets
     writeAsProbes_(false),
     outputPath_
     (
-        time_.globalPath()/functionObject::outputPrefix/name
+        time_.globalPath()/functionObject::outputPrefix
+      / name/mesh_.regionName()
     ),
     searchEngine_(mesh_),
     samplePointScheme_(),
@@ -459,10 +454,6 @@ Foam::sampledSets::sampledSets
     gatheredSorting_(),
     globalIndices_()
 {
-    if (mesh_.name() != polyMesh::defaultRegion)
-    {
-        outputPath_ /= mesh_.name();
-    }
     outputPath_.clean();  // Remove unneeded ".."
 
     read(dict);
@@ -487,7 +478,8 @@ Foam::sampledSets::sampledSets
     writeAsProbes_(false),
     outputPath_
     (
-        time_.globalPath()/functionObject::outputPrefix/name
+        time_.globalPath()/functionObject::outputPrefix
+      / name/mesh_.regionName()
     ),
     searchEngine_(mesh_),
     samplePointScheme_(),
@@ -500,10 +492,6 @@ Foam::sampledSets::sampledSets
     gatheredSorting_(),
     globalIndices_()
 {
-    if (mesh_.name() != polyMesh::defaultRegion)
-    {
-        outputPath_ /= mesh_.name();
-    }
     outputPath_.clean();  // Remove unneeded ".."
 
     read(dict);