From ec6c0d7e0fc978b0d30f24e841dee19c76c3a4ef Mon Sep 17 00:00:00 2001
From: Will Bainbridge <http://cfd.direct>
Date: Mon, 22 May 2017 12:29:27 +0100
Subject: [PATCH] cfdTools: Added a number of functions for performing volume
 averages of discontinuous fields, with the discontinuity defined by a level
 set. The functions do a proper integration of the discontinuous fields by
 tet- and tri-cutting along the plane of the level set.

---
 src/finiteVolume/Make/files                   |   1 +
 .../cfdTools/general/levelSet/levelSet.C      |   2 +-
 .../cfdTools/general/levelSet/levelSet.H      | 110 ++++++++++++++++++
 3 files changed, 112 insertions(+), 1 deletion(-)
 create mode 100644 src/finiteVolume/cfdTools/general/levelSet/levelSet.H

diff --git a/src/finiteVolume/Make/files b/src/finiteVolume/Make/files
index 3f6759d00a..abdef09778 100644
--- a/src/finiteVolume/Make/files
+++ b/src/finiteVolume/Make/files
@@ -414,6 +414,7 @@ $(general)/adjustPhi/adjustPhi.C
 $(general)/bound/bound.C
 $(general)/CorrectPhi/correctUphiBCs.C
 $(general)/pressureControl/pressureControl.C
+$(general)/levelSet/levelSet.C
 
 coupling = $(general)/coupling
 $(coupling)/externalFileCoupler.C
diff --git a/src/finiteVolume/cfdTools/general/levelSet/levelSet.C b/src/finiteVolume/cfdTools/general/levelSet/levelSet.C
index e5a3fc9489..d4d55ca431 100644
--- a/src/finiteVolume/cfdTools/general/levelSet/levelSet.C
+++ b/src/finiteVolume/cfdTools/general/levelSet/levelSet.C
@@ -119,7 +119,7 @@ Foam::tmp<Foam::scalarField> Foam::levelSetFraction
 
         vector a = vector::zero, r = vector::zero;
 
-        for(label eI = 0; eI < f.size(); ++ eI)
+        for (label eI = 0; eI < f.size(); ++eI)
         {
             const edge e = f.faceEdge(eI);
 
diff --git a/src/finiteVolume/cfdTools/general/levelSet/levelSet.H b/src/finiteVolume/cfdTools/general/levelSet/levelSet.H
new file mode 100644
index 0000000000..f7b7004a4f
--- /dev/null
+++ b/src/finiteVolume/cfdTools/general/levelSet/levelSet.H
@@ -0,0 +1,110 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2017 OpenFOAM Foundation
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+License
+    This file is part of OpenFOAM.
+
+    OpenFOAM is free software: you can redistribute it and/or modify it
+    under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    OpenFOAM is distributed in the hope that it will be useful, but WITHOUT
+    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+    FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+    for more details.
+
+    You should have received a copy of the GNU General Public License
+    along with OpenFOAM.  If not, see <http://www.gnu.org/licenses/>.
+
+Description:
+    Functions to create an averaged field from a discontinuous field defined by
+    a level-set.
+
+SourceFiles:
+    levelSet.C
+    levelSetTemplates.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef levelSet_H
+#define levelSet_H
+
+#include "DimensionedField.H"
+#include "fvMesh.H"
+#include "pointMesh.H"
+#include "volMesh.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+//- Calculate the average value of two fields, one on each side of a level set
+//  The level set and the fields are given both on the points and cell-centres.
+template<class Type>
+tmp<DimensionedField<Type, volMesh>> levelSetAverage
+(
+    const fvMesh& mesh,
+    const scalarField& levelC,
+    const scalarField& levelP,
+    const DimensionedField<Type, volMesh>& positiveC,
+    const DimensionedField<Type, pointMesh>& positiveP,
+    const DimensionedField<Type, volMesh>& negativeC,
+    const DimensionedField<Type, pointMesh>& negativeP
+);
+
+//- As the above overload, but on the faces of a patch
+template<class Type>
+tmp<Field<Type>> levelSetAverage
+(
+    const fvPatch& patch,
+    const scalarField& levelF,
+    const scalarField& levelP,
+    const Field<Type>& positiveF,
+    const Field<Type>& positiveP,
+    const Field<Type>& negativeF,
+    const Field<Type>& negativeP
+);
+
+//- Calculate the volume-fraction that a level set occupies. This gives the the
+//  same result as levelSetAverage if the fields passed to the latter are
+//  uniformly 0 and 1. The above flag flips the direction.
+tmp<DimensionedField<scalar, volMesh>> levelSetFraction
+(
+    const fvMesh& mesh,
+    const scalarField& levelC,
+    const scalarField& levelP,
+    const bool above
+);
+
+//- As the above oveload, but on the faces of a patch
+tmp<scalarField> levelSetFraction
+(
+    const fvPatch& patch,
+    const scalarField& levelF,
+    const scalarField& levelP,
+    const bool above
+);
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#ifdef NoRepository
+    #include "levelSetTemplates.C"
+#endif
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //