BUG: missing unit-normal weighting for surfaceFieldValue (fixes #2273)

- when using a vector field for weighting, it either used mag()
  or mag * area, but did not have a unit-normal projection version

src/functionObjects/field/fieldValues/volFieldValue/volFieldValue.C

@@ -84,9 +84,10 @@ Foam::functionObjects::fieldValues::volFieldValue::postOperationTypeNames_
 
 // * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
 
-bool Foam::functionObjects::fieldValues::volFieldValue::usesVol() const
+bool Foam::functionObjects::fieldValues::volFieldValue::usesVol()
+const noexcept
 {
-    // Only a few operations require the cell volume
+    // Few operations require the cell volume
     switch (operation_)
     {
         case opVolAverage:
@@ -102,33 +103,6 @@ bool Foam::functionObjects::fieldValues::volFieldValue::usesVol() const
 }
 
 
-bool Foam::functionObjects::fieldValues::volFieldValue::usesMag() const
-{
-    // Operation specifically tagged to use mag
-    return (operation_ & typeAbsolute);
-}
-
-
-bool Foam::functionObjects::fieldValues::volFieldValue::usesWeight() const
-{
-    // Operation specifically tagged to require a weight field
-    return (operation_ & typeWeighted);
-}
-
-
-bool Foam::functionObjects::fieldValues::volFieldValue::canWeight
-(
-    const scalarField& weightField
-) const
-{
-    return
-    (
-        usesWeight()
-     && returnReduce(!weightField.empty(), orOp<bool>()) // On some processor
-    );
-}
-
-
 void Foam::functionObjects::fieldValues::volFieldValue::writeFileHeader
 (
     Ostream& os
@@ -260,7 +234,7 @@ bool Foam::functionObjects::fieldValues::volFieldValue::read
 
     weightFieldNames_.clear();
 
-    if (usesWeight())
+    if (is_weightedOp())
     {
         // Can have "weightFields" or "weightField"
 

src/functionObjects/field/fieldValues/volFieldValue/volFieldValue.H

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2011-2017 OpenFOAM Foundation
-    Copyright (C) 2016-2020 OpenCFD Ltd.
+    Copyright (C) 2016-2021 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -222,17 +222,16 @@ protected:
     // Protected Member Functions
 
         //- True if the operation needs the cell-volume
-        bool usesVol() const;
+        bool usesVol() const noexcept;
 
         //- True if the operation variant uses mag
-        bool usesMag() const;
+        inline bool is_magOp() const noexcept;
 
         //- True if the operation variant uses a weight-field
-        bool usesWeight() const;
+        inline bool is_weightedOp() const noexcept;
 
-        //- True if operation variant uses a weight-field that is available.
-        //  Checks for availability on any processor.
-        inline bool canWeight(const scalarField& weightField) const;
+        //- True if field is non-empty on any processor.
+        inline bool canWeight(const scalarField& fld) const;
 
         //- Return true if the field name is valid
         template<class Type>
@@ -332,6 +331,10 @@ public:
 
 // * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
 
+#include "volFieldValueI.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
 #ifdef NoRepository
     #include "volFieldValueTemplates.C"
 #endif

src/functionObjects/field/fieldValues/volFieldValue/volFieldValueI.H

@@ -0,0 +1,56 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | www.openfoam.com
+     \\/     M anipulation  |
+-------------------------------------------------------------------------------
+    Copyright (C) 2021 OpenCFD Ltd.
+-------------------------------------------------------------------------------
+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/>.
+
+\*---------------------------------------------------------------------------*/
+
+// * * * * * * * * * * * * Protected Member Functions  * * * * * * * * * * * //
+
+inline bool Foam::functionObjects::fieldValues::volFieldValue::is_magOp()
+const noexcept
+{
+    // Operation tagged to use mag
+    return (operation_ & typeAbsolute);
+}
+
+
+inline bool Foam::functionObjects::fieldValues::volFieldValue::is_weightedOp()
+const noexcept
+{
+    // Operation tagged to require a weight field
+    return (operation_ & typeWeighted);
+}
+
+
+inline bool Foam::functionObjects::fieldValues::volFieldValue::canWeight
+(
+    const scalarField& fld
+) const
+{
+    // Non-empty on some processor
+    return returnReduce(!fld.empty(), orOp<bool>());
+}
+
+
+// ************************************************************************* //

src/functionObjects/field/fieldValues/volFieldValue/volFieldValueTemplates.C

@@ -112,7 +112,7 @@ Type Foam::functionObjects::fieldValues::volFieldValue::processValues
         case opSum:
         case opWeightedSum:
         {
-            if (canWeight(weightField))
+            if (is_weightedOp() && canWeight(weightField))
             {
                 result = gSum(weightField*values);
             }
@@ -126,7 +126,7 @@ Type Foam::functionObjects::fieldValues::volFieldValue::processValues
         case opAverage:
         case opWeightedAverage:
         {
-            if (canWeight(weightField))
+            if (is_weightedOp() && canWeight(weightField))
             {
                 result =
                     gSum(weightField*values)/(gSum(weightField) + ROOTVSMALL);
@@ -142,7 +142,7 @@ Type Foam::functionObjects::fieldValues::volFieldValue::processValues
         case opVolAverage:
         case opWeightedVolAverage:
         {
-            if (canWeight(weightField))
+            if (is_weightedOp() && canWeight(weightField))
             {
                 result = gSum(weightField*V*values)
                     /(gSum(weightField*V) + ROOTVSMALL);
@@ -157,7 +157,7 @@ Type Foam::functionObjects::fieldValues::volFieldValue::processValues
         case opVolIntegrate:
         case opWeightedVolIntegrate:
         {
-            if (canWeight(weightField))
+            if (is_weightedOp() && canWeight(weightField))
             {
                 result = gSum(weightField*V*values);
             }