Merge branch 'feature-functionObject-forceCoeffExtension' into 'develop'

ENH: functionObject: refactored co-ordinate system usage and new forceCoeffs members

See merge request OpenFOAM-plus!246

src/functionObjects/forces/forceCoeffs/forceCoeffs.C

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2015-2017 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2015-2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -42,7 +42,6 @@ namespace Foam
 namespace functionObjects
 {
     defineTypeNameAndDebug(forceCoeffs, 0);
-
     addToRunTimeSelectionTable(functionObject, forceCoeffs, dictionary);
 }
 }
@@ -61,12 +60,23 @@ void Foam::functionObjects::forceCoeffs::createFiles()
 
         if (nBin_ > 1)
         {
-            CmBinFilePtr_ = createFile("CmBin");
-            writeBinHeader("Moment coefficient bins", CmBinFilePtr_());
             CdBinFilePtr_ = createFile("CdBin");
             writeBinHeader("Drag coefficient bins", CdBinFilePtr_());
+
+            CsBinFilePtr_ = createFile("CsBin");
+            writeBinHeader("Side coefficient bins", CsBinFilePtr_());
+
             ClBinFilePtr_ = createFile("ClBin");
             writeBinHeader("Lift coefficient bins", ClBinFilePtr_());
+
+            CmRollBinFilePtr_ = createFile("CmRollBin");
+            writeBinHeader("Roll moment coefficient bins", CmRollBinFilePtr_());
+
+            CmPitchBinFilePtr_ = createFile("CmPitchBin");
+            writeBinHeader("Moment coefficient bins", CmPitchBinFilePtr_());
+
+            CmYawBinFilePtr_ = createFile("CmYawBin");
+            writeBinHeader("Yaw moment coefficient bins", CmYawBinFilePtr_());
         }
     }
 }
@@ -79,18 +89,28 @@ void Foam::functionObjects::forceCoeffs::writeIntegratedHeader
 ) const
 {
     writeHeader(os, "Force coefficients");
-    writeHeaderValue(os, "liftDir", liftDir_);
-    writeHeaderValue(os, "dragDir", dragDir_);
-    writeHeaderValue(os, "pitchAxis", pitchAxis_);
+    writeHeaderValue(os, "dragDir", coordSys_.e1());
+    writeHeaderValue(os, "sideDir", coordSys_.e2());
+    writeHeaderValue(os, "liftDir", coordSys_.e3());
+    writeHeaderValue(os, "rollAxis", coordSys_.e1());
+    writeHeaderValue(os, "pitchAxis", coordSys_.e2());
+    writeHeaderValue(os, "yawAxis", coordSys_.e3());
     writeHeaderValue(os, "magUInf", magUInf_);
     writeHeaderValue(os, "lRef", lRef_);
     writeHeaderValue(os, "Aref", Aref_);
     writeHeaderValue(os, "CofR", coordSys_.origin());
     writeHeader(os, "");
     writeCommented(os, "Time");
-    writeTabbed(os, "Cm");
     writeTabbed(os, "Cd");
+    writeTabbed(os, "Cs");
     writeTabbed(os, "Cl");
+    writeTabbed(os, "CmRoll");
+    writeTabbed(os, "CmPitch");
+    writeTabbed(os, "CmYaw");
+    writeTabbed(os, "Cd(f)");
+    writeTabbed(os, "Cd(r)");
+    writeTabbed(os, "Cs(f)");
+    writeTabbed(os, "Cs(r)");
     writeTabbed(os, "Cl(f)");
     writeTabbed(os, "Cl(r)");
     os  << endl;
@@ -114,30 +134,30 @@ void Foam::functionObjects::forceCoeffs::writeBinHeader
     forAll(binPoints, pointi)
     {
         binPoints[pointi] = (binMin_ + (pointi + 1)*binDx_)*binDir_;
-        os << tab << binPoints[pointi].x();
+        os  << tab << binPoints[pointi].x();
     }
-    os << nl;
+    os  << nl;
 
     writeCommented(os, "y co-ords  :");
     forAll(binPoints, pointi)
     {
-        os << tab << binPoints[pointi].y();
+        os  << tab << binPoints[pointi].y();
     }
-    os << nl;
+    os  << nl;
 
     writeCommented(os, "z co-ords  :");
     forAll(binPoints, pointi)
     {
-        os << tab << binPoints[pointi].z();
+        os  << tab << binPoints[pointi].z();
     }
-    os << nl;
+    os  << nl;
 
     writeHeader(os, "");
     writeCommented(os, "Time");
 
-    for (label j = 0; j < nBin_; j++)
+    for (label j = 0; j < nBin_; ++j)
     {
-        word jn(Foam::name(j) + ':');
+        const word jn(Foam::name(j) + ':');
         writeTabbed(os, jn + "total");
         writeTabbed(os, jn + "pressure");
         writeTabbed(os, jn + "viscous");
@@ -163,13 +183,13 @@ void Foam::functionObjects::forceCoeffs::writeIntegratedData
         return;
     }
 
-    scalar pressure = sum(coeff[0]);
-    scalar viscous = sum(coeff[1]);
-    scalar porous = sum(coeff[2]);
-    scalar total = pressure + viscous + porous;
+    const scalar pressure = sum(coeff[0]);
+    const scalar viscous = sum(coeff[1]);
+    const scalar porous = sum(coeff[2]);
+    const scalar total = pressure + viscous + porous;
 
     Info<< "        " << title << "       : " << total << token::TAB
-        << "("
+        << '('
         << "pressure: " << pressure << token::TAB
         << "viscous: " << viscous;
 
@@ -178,7 +198,7 @@ void Foam::functionObjects::forceCoeffs::writeIntegratedData
         Info<< token::TAB << "porous: " << porous;
     }
 
-    Info<< ")" << endl;
+    Info<< ')' << endl;
 }
 
 
@@ -190,7 +210,7 @@ void Foam::functionObjects::forceCoeffs::writeBinData
 {
     writeTime(os);
 
-    for (label bini = 0; bini < nBin_; bini++)
+    for (label bini = 0; bini < nBin_; ++bini)
     {
         scalar total = coeffs[0][bini] + coeffs[1][bini] + coeffs[2][bini];
 
@@ -216,45 +236,35 @@ Foam::functionObjects::forceCoeffs::forceCoeffs
 )
 :
     forces(name, runTime, dict),
-    liftDir_(Zero),
-    dragDir_(Zero),
-    pitchAxis_(Zero),
-    magUInf_(0.0),
-    lRef_(0.0),
-    Aref_(0.0),
+    magUInf_(Zero),
+    lRef_(Zero),
+    Aref_(Zero),
     coeffFilePtr_(),
-    CmBinFilePtr_(),
     CdBinFilePtr_(),
-    ClBinFilePtr_()
+    CsBinFilePtr_(),
+    ClBinFilePtr_(),
+    CmRollBinFilePtr_(),
+    CmPitchBinFilePtr_(),
+    CmYawBinFilePtr_()
 {
     read(dict);
+    setCoordinateSystem(dict, "liftDir", "dragDir");
     Info<< endl;
 }
 
 
-// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
-
-Foam::functionObjects::forceCoeffs::~forceCoeffs()
-{}
-
-
 // * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
 
 bool Foam::functionObjects::forceCoeffs::read(const dictionary& dict)
 {
     forces::read(dict);
 
-    // Directions for lift and drag forces, and pitch moment
-    dict.readEntry("liftDir", liftDir_);
-    dict.readEntry("dragDir", dragDir_);
-    dict.readEntry("pitchAxis", pitchAxis_);
-
     // Free stream velocity magnitude
     dict.readEntry("magUInf", magUInf_);
 
     // If case is compressible we must read rhoInf (store in rhoRef_) to
     // calculate the reference dynamic pressure
-    // - note: for incompressible, rhoRef_ is already initialised
+    // Note: for incompressible, rhoRef_ is already initialised
     if (rhoName_ != "rhoInf")
     {
         dict.readEntry("rhoInf", rhoRef_);
@@ -315,55 +325,94 @@ bool Foam::functionObjects::forceCoeffs::execute()
 
     createFiles();
 
-    scalar pDyn = 0.5*rhoRef_*magUInf_*magUInf_;
-
     // Storage for pressure, viscous and porous contributions to coeffs
-    List<Field<scalar>> momentCoeffs(3);
     List<Field<scalar>> dragCoeffs(3);
+    List<Field<scalar>> sideCoeffs(3);
     List<Field<scalar>> liftCoeffs(3);
+    List<Field<scalar>> rollMomentCoeffs(3);
+    List<Field<scalar>> pitchMomentCoeffs(3);
+    List<Field<scalar>> yawMomentCoeffs(3);
+
     forAll(liftCoeffs, i)
     {
-        momentCoeffs[i].setSize(nBin_);
         dragCoeffs[i].setSize(nBin_);
+        sideCoeffs[i].setSize(nBin_);
         liftCoeffs[i].setSize(nBin_);
+        rollMomentCoeffs[i].setSize(nBin_);
+        pitchMomentCoeffs[i].setSize(nBin_);
+        yawMomentCoeffs[i].setSize(nBin_);
     }
 
     // Calculate coefficients
-    scalar CmTot = 0;
     scalar CdTot = 0;
+    scalar CsTot = 0;
     scalar ClTot = 0;
+    scalar CmRollTot = 0;
+    scalar CmPitchTot = 0;
+    scalar CmYawTot = 0;
+
+    const scalar pDyn = 0.5*rhoRef_*sqr(magUInf_);
+
+    // Avoid divide by zero in 2D cases
+    const scalar momentScaling = 1.0/(Aref_*pDyn*lRef_ + SMALL);
+    const scalar forceScaling = 1.0/(Aref_*pDyn + SMALL);
+
     forAll(liftCoeffs, i)
     {
-        momentCoeffs[i] = (moment_[i] & pitchAxis_)/(Aref_*pDyn*lRef_);
-        dragCoeffs[i] = (force_[i] & dragDir_)/(Aref_*pDyn);
-        liftCoeffs[i] = (force_[i] & liftDir_)/(Aref_*pDyn);
+        const Field<vector> localForce(coordSys_.localVector(force_[i]));
+        const Field<vector> localMoment(coordSys_.localVector(moment_[i]));
+
+        dragCoeffs[i] = forceScaling*(localForce.component(0));
+        sideCoeffs[i] = forceScaling*(localForce.component(1));
+        liftCoeffs[i] = forceScaling*(localForce.component(2));
+        rollMomentCoeffs[i] = momentScaling*(localMoment.component(0));
+        pitchMomentCoeffs[i] = momentScaling*(localMoment.component(1));
+        yawMomentCoeffs[i] = momentScaling*(localMoment.component(2));
 
-        CmTot += sum(momentCoeffs[i]);
         CdTot += sum(dragCoeffs[i]);
+        CsTot += sum(sideCoeffs[i]);
         ClTot += sum(liftCoeffs[i]);
+        CmRollTot += sum(rollMomentCoeffs[i]);
+        CmPitchTot += sum(pitchMomentCoeffs[i]);
+        CmYawTot += sum(yawMomentCoeffs[i]);
     }
 
-    scalar ClfTot = ClTot/2.0 + CmTot;
-    scalar ClrTot = ClTot/2.0 - CmTot;
+    // Single contributions to the front and rear
+    const scalar CdfTot = 0.5*CdTot + CmRollTot;
+    const scalar CdrTot = 0.5*CdTot - CmRollTot;
+    const scalar CsfTot = 0.5*CsTot + CmYawTot;
+    const scalar CsrTot = 0.5*CsTot - CmYawTot;
+    const scalar ClfTot = 0.5*ClTot + CmPitchTot;
+    const scalar ClrTot = 0.5*ClTot - CmPitchTot;
 
     Log << type() << " " << name() << " execute:" << nl
         << "    Coefficients" << nl;
 
-    writeIntegratedData("Cm", momentCoeffs);
     writeIntegratedData("Cd", dragCoeffs);
+    writeIntegratedData("Cs", sideCoeffs);
     writeIntegratedData("Cl", liftCoeffs);
+    writeIntegratedData("CmRoll", rollMomentCoeffs);
+    writeIntegratedData("CmPitch", pitchMomentCoeffs);
+    writeIntegratedData("CmYaw", yawMomentCoeffs);
+
+    Log << "        Cd(f)    : " << CdfTot << nl
+        << "        Cd(r)    : " << CdrTot << nl;
+
+    Log << "        Cs(f)    : " << CsfTot << nl
+        << "        Cs(r)    : " << CsrTot << nl;
 
     Log << "        Cl(f)    : " << ClfTot << nl
-        << "        Cl(r)    : " << ClrTot << nl
-        << endl;
+        << "        Cl(r)    : " << ClrTot << nl;
 
     if (writeToFile())
     {
         writeTime(coeffFilePtr_());
         coeffFilePtr_()
-            << tab << CmTot << tab  << CdTot
-            << tab << ClTot << tab << ClfTot << tab << ClrTot << endl;
-
+            << tab << CdTot << tab << CsTot << tab << ClTot
+            << tab << CmRollTot << tab << CmPitchTot << tab << CmYawTot
+            << tab << CdfTot << tab << CdrTot
+            << tab << CsfTot << tab << CsrTot
+            << tab << ClfTot << tab << ClrTot << endl;
 
         if (nBin_ > 1)
         {
@@ -371,26 +420,41 @@ bool Foam::functionObjects::forceCoeffs::execute()
             {
                 forAll(liftCoeffs, i)
                 {
-                    for (label bini = 1; bini < nBin_; bini++)
+                    for (label bini = 1; bini < nBin_; ++bini)
                     {
-                        liftCoeffs[i][bini] += liftCoeffs[i][bini-1];
                         dragCoeffs[i][bini] += dragCoeffs[i][bini-1];
-                        momentCoeffs[i][bini] += momentCoeffs[i][bini-1];
+                        sideCoeffs[i][bini] += sideCoeffs[i][bini-1];
+                        liftCoeffs[i][bini] += liftCoeffs[i][bini-1];
+                        rollMomentCoeffs[i][bini] +=
+                            rollMomentCoeffs[i][bini-1];
+                        pitchMomentCoeffs[i][bini] +=
+                            pitchMomentCoeffs[i][bini-1];
+                        yawMomentCoeffs[i][bini] += yawMomentCoeffs[i][bini-1];
                     }
                 }
             }
 
             writeBinData(dragCoeffs, CdBinFilePtr_());
+            writeBinData(sideCoeffs, CsBinFilePtr_());
             writeBinData(liftCoeffs, ClBinFilePtr_());
-            writeBinData(momentCoeffs, CmBinFilePtr_());
+            writeBinData(rollMomentCoeffs, CmRollBinFilePtr_());
+            writeBinData(pitchMomentCoeffs, CmPitchBinFilePtr_());
+            writeBinData(yawMomentCoeffs, CmYawBinFilePtr_());
         }
     }
 
     // Write state/results information
     {
-        setResult("Cm", CmTot);
         setResult("Cd", CdTot);
+        setResult("Cs", CsTot);
         setResult("Cl", ClTot);
+        setResult("CmRoll", CmRollTot);
+        setResult("CmPitch", CmPitchTot);
+        setResult("CmYaw", CmYawTot);
+        setResult("Cd(f)", CdfTot);
+        setResult("Cd(r)", CdrTot);
+        setResult("Cs(f)", CsfTot);
+        setResult("Cs(r)", CsrTot);
         setResult("Cl(f)", ClfTot);
         setResult("Cl(r)", ClrTot);
     }

src/functionObjects/forces/forceCoeffs/forceCoeffs.H

@@ -2,7 +2,7 @@
   =========                 |
   \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
    \\    /   O peration     |
-    \\  /    A nd           | Copyright (C) 2015 OpenCFD Ltd.
+    \\  /    A nd           | Copyright (C) 2019 OpenCFD Ltd.
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
                             | Copyright (C) 2011-2016 OpenFOAM Foundation
@@ -30,9 +30,18 @@ Group
     grpForcesFunctionObjects
 
 Description
-    Extends the forces functionObject by providing lift, drag and moment
-    coefficients.  The data can optionally be output into bins, defined in a
-    given direction.
+    Extends the \c forces functionObject by providing coefficients for:
+    - drag, side and lift forces (Cd, Cs, and Cl)
+    - roll, pitch and yaw moments (CmRoll, CmPitch, and CmYaw)
+    - front and rear axle force contributions (C(f) and C(r)) wherein
+
+    \verbatim
+        Cd(f/r) = 0.5*Cd \pm CmRoll
+        Cs(f/r) = 0.5*Cs \pm CmYaw
+        Cl(f/r) = 0.5*Cl \pm CmPitch
+    \endverbatim
+
+    The data can optionally be output into bins, defined in a given direction.
 
     The binned data provides the total and consitituent components per bin:
     - total coefficient
@@ -43,9 +52,12 @@ Description
     Data is written into multiple files in the
     postProcessing/\<functionObjectName\> directory:
     - coefficient.dat   : integrated coefficients over all geometries
-    - CmBin.dat         : moment coefficient bins
     - CdBin.dat         : drag coefficient bins
+    - CsBin.dat         : side coefficient bins
     - ClBin.dat         : lift coefficient bins
+    - CmRollBin.dat     : roll moment coefficient bins
+    - CmPitchBin.dat    : pitch moment coefficient bins
+    - CmYawBin.dat      : yaw moment coefficient bins
 
 Usage
     Example of function object specification:
@@ -58,12 +70,14 @@ Usage
         log         yes;
         writeFields yes;
         patches     (walls);
-        liftDir     (0 1 0);
-        dragDir     (-1 0 0);
-        pitchAxis   (0 0 1);
+
+        // input keywords for directions of force/moment coefficients
+        // refer below for options, and relations
+
         magUInf     100;
         lRef        3.5;
         Aref        2.2;
+        porosity    no;
 
         binData
         {
@@ -76,26 +90,65 @@ Usage
 
     Where the entries comprise:
     \table
-        Property     | Description             | Required    | Default value
-        type         | Type name: forceCoeffs  | yes         |
-        log          | Write force data to standard output | no | no
-        writeFields  | Write the force and moment coefficient fields | no | no
+        Property     | Description                          | Required | Default
+        type         | Type name: forceCoeffs               | yes |
+        log          | Write force data to standard output  | no  | no
+        writeFields  | Write force,moment coefficient fields | no | no
         patches      | Patches included in the forces calculation | yes |
-        liftDir      | Lift direction          | yes         |
-        dragDir      | Drag direction          | yes         |
-        pitchAxis    | Picth axis              | yes         |
-        magUInf      | Free stream velocity magnitude | yes  |
+        magUInf      | Free stream velocity magnitude       | yes |
         lRef         | Reference length scale for moment calculations | yes |
-        Aref         | Reference area          | yes |
-        porosity     | Flag to include porosity contributions | no | no
+        Aref         | Reference area                       | yes |
+        porosity     | Include porosity contributions       | no  | false
     \endtable
 
     Bin data is optional, but if the dictionary is present, the entries must
-    be defined according o
+    be defined according to following:
     \table
-        nBin         | number of data bins     | yes         |
-        direction    | direction along which bins are defined | yes |
-        cumulative   | bin data accumulated with incresing distance | yes |
+        nBin         | Number of data bins                    | yes |
+        direction    | Direction along which bins are defined | yes |
+        cumulative   | Bin data accumulated with incresing distance | yes |
+    \endtable
+
+    Input of force/moment coefficient directions:
+    - require an origin, and two orthogonal directions; the remaining orthogonal
+    direction is determined accordingly.
+    - can be added by the three options below.
+
+    \verbatim
+        CofR        (0 0 0); // Centre of rotation
+        dragDir     (1 0 0);
+        liftDir     (0 0 1);
+    \endverbatim
+
+    \verbatim
+        origin (0 0 0);
+        e1     (1 0 0);
+        e3     (0 0 1); // combinations: (e1, e2) or (e2, e3) or (e3, e1)
+    \endverbatim
+
+    \verbatim
+        coordinateSystem
+        {
+            origin  (0 0 0);
+            rotation
+            {
+                type axes;
+                e1 (1 0 0);
+                e3 (0 0 1); // combinations: (e1, e2) or (e2, e3) or (e3, e1)
+            }
+        }
+    \endverbatim
+
+    The default direction relations are shown below:
+
+    \table
+        Property     | Description           | Alias | Direction
+        dragDir      | Drag direction        | e1    | (1 0 0)
+        sideDir      | Side force direction  | e2    | (0 1 0)
+        liftDir      | Lift direction        | e3    | (0 0 1)
+        rollAxis     | Roll axis             | e1    | (1 0 0)
+        pitchAxis    | Pitch axis            | e2    | (0 1 0)
+        yawAxis      | Yaw axis              | e3    | (0 0 1)
     \endtable
 
 See also
@@ -130,30 +183,18 @@ class forceCoeffs
 {
     // Private data
 
-        // Force coefficient geometry
-
-            //- Lift
-            vector liftDir_;
-
-            //- Drag
-            vector  dragDir_;
-
-            //- Pitch
-            vector pitchAxis_;
-
-
         // Free-stream conditions
 
-            //- Velocity magnitude
+            //- Free-stream velocity magnitude
             scalar magUInf_;
 
 
         // Reference scales
 
-            //- Length
+            //- Reference length [m]
             scalar lRef_;
 
-            //- Area
+            //- Reference area [m^2]
             scalar Aref_;
 
 
@@ -162,15 +203,24 @@ class forceCoeffs
             //- Integrated coefficients
             autoPtr<OFstream> coeffFilePtr_;
 
-            //- Moment coefficient
-            autoPtr<OFstream> CmBinFilePtr_;
-
             //- Drag coefficient
             autoPtr<OFstream> CdBinFilePtr_;
 
+            //- Side coefficient
+            autoPtr<OFstream> CsBinFilePtr_;
+
             //- Lift coefficient
             autoPtr<OFstream> ClBinFilePtr_;
 
+            //- Roll moment coefficient
+            autoPtr<OFstream> CmRollBinFilePtr_;
+
+            //- Pitch moment coefficient
+            autoPtr<OFstream> CmPitchBinFilePtr_;
+
+            //- Yaw moment coefficient
+            autoPtr<OFstream> CmYawBinFilePtr_;
+
 
     // Private Member Functions
 
@@ -223,7 +273,7 @@ public:
 
 
     //- Destructor
-    virtual ~forceCoeffs();
+    virtual ~forceCoeffs() = default;
 
 
     // Member Functions
@@ -231,7 +281,7 @@ public:
         //- Read the forces data
         virtual bool read(const dictionary&);
 
-        //- Execute, currently does nothing
+        //- Execute
         virtual bool execute();
 
         //- Write the forces
@@ -249,3 +299,4 @@ public:
 #endif
 
 // ************************************************************************* //
+

src/functionObjects/forces/forces/forces.C

@@ -71,22 +71,6 @@ void Foam::functionObjects::forces::createFiles()
             momentBinFilePtr_ = createFile("momentBin");
             writeBinHeader("Moment", momentBinFilePtr_());
         }
-
-        if (localSystem_)
-        {
-            localForceFilePtr_ = createFile("localForce");
-            writeIntegratedHeader("Force", localForceFilePtr_());
-            localMomentFilePtr_ = createFile("localMoment");
-            writeIntegratedHeader("Moment", localMomentFilePtr_());
-
-            if (nBin_ > 1)
-            {
-                localForceBinFilePtr_ = createFile("localForceBin");
-                writeBinHeader("Force", localForceBinFilePtr_());
-                localMomentBinFilePtr_ = createFile("localMomentBin");
-                writeBinHeader("Moment", localMomentBinFilePtr_());
-            }
-        }
     }
 }
 
@@ -169,6 +153,49 @@ void Foam::functionObjects::forces::writeBinHeader