STYLE: effectivenessHeatExchangerSource: modernise code

- removed redundant protected scope
- removed undefined 'calculateTotalArea' function
- reordered the constructor list

DOC: effectivenessHeatExchangerSource: improve header documentation

src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.C

@@ -75,7 +75,7 @@ void Foam::fv::effectivenessHeatExchangerSource::initialise()
     label count = 0;
     forAll(fZone, i)
     {
-        label facei = fZone[i];
+        const label facei = fZone[i];
         label faceId = -1;
         label facePatchId = -1;
         if (mesh_.isInternalFace(facei))
@@ -156,8 +156,8 @@ Foam::fv::effectivenessHeatExchangerSource::effectivenessHeatExchangerSource
 :
     fv::cellSetOption(name, modelType, dict, mesh),
     writeFile(mesh, name, modelType, coeffs_),
-    secondaryMassFlowRate_(0),
+    userPrimaryInletT_(false),
-    secondaryInletT_(0),
+    targetQdotActive_(false),
     secondaryCpPtr_
     (
         Function1<scalar>::NewIfPresent
@@ -168,13 +168,13 @@ Foam::fv::effectivenessHeatExchangerSource::effectivenessHeatExchangerSource
             &mesh
         )
     ),
-    primaryInletT_(0),
-    userPrimaryInletT_(false),
-    targetQdotActive_(false),
-    targetQdot_(0),
-    targetQdotCalcInterval_(5),
-    targetQdotRelax_(0.5),
     eTable_(),
+    targetQdotCalcInterval_(5),
+    secondaryMassFlowRate_(0),
+    secondaryInletT_(0),
+    primaryInletT_(0),
+    targetQdot_(0),
+    targetQdotRelax_(0.5),
     UName_("U"),
     TName_("T"),
     phiName_("phi"),
@@ -212,12 +212,10 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
 )
 {
     const auto& thermo = mesh_.lookupObject<basicThermo>(basicThermo::dictName);
+    const auto& phi = mesh_.lookupObject<surfaceScalarField>(phiName_);
+    const auto& T = mesh_.lookupObject<volScalarField>(TName_);
 
     const surfaceScalarField Cpf(fvc::interpolate(thermo.Cp()));
-
-    const auto& phi = mesh_.lookupObject<surfaceScalarField>(phiName_);
-
-    const auto& T = mesh_.lookupObject<volScalarField>(TName_);
     const surfaceScalarField Tf(fvc::interpolate(T));
 
     scalar sumPhi = 0;
@@ -226,29 +224,30 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
     scalar primaryInletTfMean = 0;
     forAll(faceId_, i)
     {
-        label facei = faceId_[i];
+        const label facei = faceId_[i];
         if (facePatchId_[i] != -1)
         {
-            label patchi = facePatchId_[i];
+            const label patchi = facePatchId_[i];
-            scalar phii = phi.boundaryField()[patchi][facei]*faceSign_[i];
+            const scalar phii = phi.boundaryField()[patchi][facei]*faceSign_[i];
+            const scalar magPhii = mag(phii);
 
             sumPhi += phii;
-
-            scalar Cpfi = Cpf.boundaryField()[patchi][facei];
-            scalar Tfi = Tf.boundaryField()[patchi][facei];
-            scalar magPhii = mag(phii);
-
             sumMagPhi += magPhii;
+
+            const scalar Cpfi = Cpf.boundaryField()[patchi][facei];
+            const scalar Tfi = Tf.boundaryField()[patchi][facei];
+
             CpfMean += Cpfi*magPhii;
             primaryInletTfMean += Tfi*magPhii;
         }
         else
         {
-            scalar phii = phi[facei]*faceSign_[i];
+            const scalar phii = phi[facei]*faceSign_[i];
-            scalar magPhii = mag(phii);
+            const scalar magPhii = mag(phii);
 
             sumPhi += phii;
             sumMagPhi += magPhii;
+
             CpfMean += Cpf[facei]*magPhii;
             primaryInletTfMean += Tf[facei]*magPhii;
         }
@@ -265,9 +264,9 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
         primaryInletT = primaryInletTfMean/(sumMagPhi + ROOTVSMALL);
     }
 
-    const scalar alpha =
+    const scalar effectiveness = eTable_()(mag(sumPhi), secondaryMassFlowRate_);
-        eTable_()(mag(sumPhi), secondaryMassFlowRate_)
+
-       *CpfMean*mag(sumPhi);
+    const scalar alpha = effectiveness*CpfMean*mag(sumPhi);
 
     const scalar Qt = alpha*(secondaryInletT_ - primaryInletT);
 
@@ -277,7 +276,7 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
      && (mesh_.time().timeIndex() % targetQdotCalcInterval_ == 0)
     )
     {
-        scalar dT = (targetQdot_ - Qt)/(alpha + ROOTVSMALL);
+        const scalar dT = (targetQdot_ - Qt)/(alpha + ROOTVSMALL);
         secondaryInletT_ += targetQdotRelax_*dT;
     }
 
@@ -289,7 +288,7 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
         Tref = gMax(TCells);
         forAll(deltaTCells, i)
         {
-            deltaTCells[i] = max(Tref - TCells[i], 0.0);
+            deltaTCells[i] = max(Tref - TCells[i], scalar(0));
         }
     }
     else
@@ -297,7 +296,7 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
         Tref = gMin(TCells);
         forAll(deltaTCells, i)
         {
-            deltaTCells[i] = max(TCells[i] - Tref, 0.0);
+            deltaTCells[i] = max(TCells[i] - Tref, scalar(0));
         }
     }
 
@@ -307,7 +306,7 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
     scalar sumWeight = 0;
     forAll(cells_, i)
     {
-        label celli = cells_[i];
+        const label celli = cells_[i];
         sumWeight += V[celli]*mag(U[celli])*deltaTCells[i];
     }
     reduce(sumWeight, sumOp<scalar>());
@@ -318,21 +317,21 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
 
         forAll(cells_, i)
         {
-            label celli = cells_[i];
+            const label celli = cells_[i];
             heSource[celli] -=
                 Qt*V[celli]*mag(U[celli])*deltaTCells[i]
                /(sumWeight + ROOTVSMALL);
         }
     }
 
-    Info<< nl
+    Log << nl
         << type() << ": " << name() << nl << incrIndent
-        << indent << "Net mass flux [Kg/s]      : " << sumPhi << nl
+        << indent << "Net mass flux [kg/s]      : " << sumPhi << nl
         << indent << "Total heat exchange [W]   : " << Qt << nl
         << indent << "Secondary inlet T [K]     : " << secondaryInletT_ << nl
         << indent << "Tref [K]                  : " << Tref << nl
-        << indent << "Effectiveness             : "
+        << indent << "Effectiveness             : " << effectiveness
-        << eTable_()(mag(sumPhi), secondaryMassFlowRate_) << decrIndent;
+        << decrIndent;
 
     if (Pstream::master())
     {
@@ -343,7 +342,7 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
             << tab << Qt
             << tab << secondaryInletT_
             << tab << Tref
-            << tab << eTable_()(mag(sumPhi), secondaryMassFlowRate_);
+            << tab << effectiveness;
 
         if (secondaryCpPtr_)
         {
@@ -352,7 +351,7 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
             const scalar secondaryOutletT =
                 Qt/(secondaryMassFlowRate_*secondaryCp) + secondaryInletT_;
 
-            Info<< nl << incrIndent << indent
+            Log << nl << incrIndent << indent
                 << "Secondary outlet T [K]    : " << secondaryOutletT
                 << decrIndent;
 
@@ -367,55 +366,55 @@ void Foam::fv::effectivenessHeatExchangerSource::addSup
 
 bool Foam::fv::effectivenessHeatExchangerSource::read(const dictionary& dict)
 {
-    if (fv::cellSetOption::read(dict) && writeFile::read(dict))
+    if (!(fv::cellSetOption::read(dict) && writeFile::read(dict)))
     {
-        UName_ = coeffs_.getOrDefault<word>("U", "U");
+        return false;
-        TName_ = coeffs_.getOrDefault<word>("T", "T");
-        phiName_ = coeffs_.getOrDefault<word>("phi", "phi");
-        coeffs_.readEntry("faceZone", faceZoneName_);
-
-        coeffs_.readEntry("secondaryMassFlowRate", secondaryMassFlowRate_);
-        coeffs_.readEntry("secondaryInletT", secondaryInletT_);
-
-        if (coeffs_.readIfPresent("primaryInletT", primaryInletT_))
-        {
-            userPrimaryInletT_ = true;
-            Info<< type() << " " << this->name() << ": " << indent << nl
-                << "employing user-specified primary flow inlet temperature: "
-                << primaryInletT_ << endl;
-        }
-        else
-        {
-            Info<< type() << " " << this->name() << ": " << indent << nl
-                << "employing flux-weighted primary flow inlet temperature"
-                << endl;
-        }
-
-        if (coeffs_.readIfPresent("targetQdot", targetQdot_))
-        {
-            targetQdotActive_ = true;
-            Info<< indent << "employing target heat rejection of "
-                << targetQdot_ << nl;
-
-            coeffs_.readIfPresent
-            (
-                "targetQdotCalcInterval",
-                targetQdotCalcInterval_
-            );
-
-            Info<< indent << "updating secondary inlet temperature every "
-                << targetQdotCalcInterval_ << " iterations" << nl;
-
-            coeffs_.readIfPresent("targetQdotRelax", targetQdotRelax_);
-
-            Info<< indent << "temperature relaxation:  "
-                << targetQdotRelax_ << endl;
-        }
-
-        return true;
     }
 
-    return false;
+    coeffs_.readEntry("secondaryMassFlowRate", secondaryMassFlowRate_);
+    coeffs_.readEntry("secondaryInletT", secondaryInletT_);
+
+    if (coeffs_.readIfPresent("primaryInletT", primaryInletT_))
+    {
+        userPrimaryInletT_ = true;
+        Info<< type() << " " << this->name() << ": " << indent << nl
+            << "employing user-specified primary flow inlet temperature: "
+            << primaryInletT_ << endl;
+    }
+    else
+    {
+        Info<< type() << " " << this->name() << ": " << indent << nl
+            << "employing flux-weighted primary flow inlet temperature"
+            << endl;
+    }
+
+    if (coeffs_.readIfPresent("targetQdot", targetQdot_))
+    {
+        targetQdotActive_ = true;
+        Info<< indent << "employing target heat rejection of "
+            << targetQdot_ << nl;
+
+        coeffs_.readIfPresent
+        (
+            "targetQdotCalcInterval",
+            targetQdotCalcInterval_
+        );
+
+        Info<< indent << "updating secondary inlet temperature every "
+            << targetQdotCalcInterval_ << " iterations" << nl;
+
+        coeffs_.readIfPresent("targetQdotRelax", targetQdotRelax_);
+
+        Info<< indent << "temperature relaxation:  "
+            << targetQdotRelax_ << endl;
+    }
+
+    UName_ = coeffs_.getOrDefault<word>("U", "U");
+    TName_ = coeffs_.getOrDefault<word>("T", "T");
+    phiName_ = coeffs_.getOrDefault<word>("phi", "phi");
+    coeffs_.readEntry("faceZone", faceZoneName_);
+
+    return true;
 }
 
 

src/fvOptions/sources/derived/effectivenessHeatExchangerSource/effectivenessHeatExchangerSource.H

@@ -6,7 +6,7 @@
      \\/     M anipulation  |
 -------------------------------------------------------------------------------
     Copyright (C) 2013-2017 OpenFOAM Foundation
-    Copyright (C) 2016-2020 OpenCFD Ltd.
+    Copyright (C) 2016-2022 OpenCFD Ltd.
 -------------------------------------------------------------------------------
 License
     This file is part of OpenFOAM.
@@ -31,8 +31,8 @@ Group
     grpFvOptionsSources
 
 Description
-    Heat exchanger source model for compressible flows, in which the heat
+    Heat exchanger source model for compressible flows, where the heat
-    exchanger is defined as an energy source using a selection of cells.
+    exchanger is modelled as an energy source using a selection of cells.
 
     The total heat exchange source is given by:
     \f[
@@ -41,13 +41,13 @@ Description
 
     where:
     \vartable
-        Q_t       | total heat source
+        Q_t       | Total heat exchange source [J/s]
-        e(\phi,\dot{m}_2) | effectivenes table
+        e(\phi,\dot{m}_2) | Effectivenes table [-]
-        \phi      | net mass flux entering heat exchanger [kg/s]
+        \phi      | Net mass flux entering heat exchanger [kg/s]
-        \dot{m}_2 | secondary mass flow rate [kg/s]
+        \dot{m}_2 | Secondary flow mass flow rate [kg/s]
-        T_1       | primary inlet temperature [K]
+        T_1       | Primary flow inlet temperature [K]
-        T_2       | secondary inlet temperature [K]
+        T_2       | Secondary flow inlet temperature [K]
-        c_p       | specific heat capacity [J/kg/K]
+        c_p       | Primary flow specific heat capacity [J/kg/K]
     \endvartable
 
 
@@ -58,11 +58,11 @@ Description
 
     where:
     \vartable
-        Q_c     | source for cell
+        Q_c     | Source for cell
-        V_c     | volume of the cell [m3]
+        V_c     | Volume of the cell [m3]
-        U_c     | local cell velocity [m/s]
+        U_c     | Local cell velocity [m/s]
-        T_c     | local call temperature [K]
+        T_c     | Local cell temperature [K]
-        T_{ref} | min or max(T) in cell zone depending on the sign of Q_t [K]
+        T_{ref} | Min or max(T) in cell zone depending on the sign of Qt [K]
     \endvartable
 
     Sources applied to either of the below, if exist:
@@ -83,63 +83,69 @@ Usage
     \verbatim
     effectivenessHeatExchangerSource1
     {
-        // Mandatory entries (unmodifiable)
+        // Mandatory entries
-        type                effectivenessHeatExchangerSource;
+        type                     effectivenessHeatExchangerSource;
-
-        // Mandatory entries (runtime modifiable)
         faceZone                 <faceZoneName>;
-        secondaryMassFlowRate    1.0;
+        secondaryMassFlowRate    <scalar>;
-        secondaryInletT          336;
+        secondaryInletT          <scalar>;
-
+        file                     "effectivenessTable";
         outOfBounds              clamp;
-        file                     "effTable";
 
-        // Optional entries (runtime modifiable)
+        // Optional entries
-        primaryInletT            293;
+        U                        <word>;
-        targetQdot               1500;
+        T                        <word>;
-        U                        <Uname>;
+        phi                      <word>;
-        T                        <Tname>;
-        phi                      <phiName>;
 
-        // Conditional optional entries (runtime modifiable)
+        // Conditional optional entries
 
-            // when the entry "targetQdot" is present
+            // when the total heat exchange is calculated with primary inlet T
-            targetQdotCalcInterval  1;
+            primaryInletT           <scalar>;
-            targetQdotRelax         1.0;
 
-        // Mandatory/Optional (inherited) entries
+            // when the total heat exchange is calculated with a given target
+            targetQdot              <scalar>;
+            targetQdotCalcInterval  <label>;
+            targetQdotRelax         <scalar>;
+
+            // when secondary outlet temperature is requested
+            secondaryCp             <Function1<scalar>>;
+
+        // Inherited entries
         ...
     }
     \endverbatim
 
     where the entries mean:
     \table
-      Property  | Description                       | Type  | Reqd | Dflt
+      Property  | Description                       | Type  | Reqd | Deflt
       type      | Type name: effectivenessHeatExchangerSource <!--
                 -->                                 | word  | yes  | -
       secondaryMassFlowRate | Secondary flow mass rate [kg/s] <!--
                 -->                                 | scalar | yes | -
-      secondaryInletT | Inlet secondary temperature [K]       <!--
+      secondaryInletT | Secondary flow inlet temperature [K]  <!--
                 -->                                 | scalar | yes | -
-      faceZone  | Name of the faceZone at the heat exchange inlet <!--
+      faceZone  | Name of the faceZone at the heat exchanger inlet <!--
                 -->                                 | word   | yes | -
-      file       | 2D look up table efficiency = function of primary <!--
+      file      | 2D effectiveness table = function of primary    <!--
                 --> and secondary mass flow rates [kg/s] | file | yes | -
-      primaryInletT | Primary air temperature at the heat exchanger inlet <!--
+      primaryInletT | Primary flow temperature at the heat exchanger inlet <!--
                 -->                                 | scalar | no  | -
       targetQdot |  Target heat rejection           | scalar | no  | -
       targetQdotCalcInterval | Target heat rejection calculation interval <!--
                 -->                                 | label  | no  | -
       targetQdotRelax | Target heat rejection temperature <!--
                 --> under-relaxation coefficient    | scalar | no  | -
-      U          | Name of operand velocity field   | word   | no  | U
+      secondaryCp | Secondary flow specific heat capacity <!--
-      T          | Name of operand temperature field  | word   | no  | T
+                -->                    | Function1\<scalar\> | no  | -
-      phi        | Name of operand flux field   | word   | no  | phi
+      U         | Name of operand velocity field    | word   | no  | U
+      T         | Name of operand temperature field | word   | no  | T
+      phi       | Name of operand flux field        | word   | no  | phi
     \endtable
 
     The inherited entries are elaborated in:
-     - \link fvOption.H \endlink
+      - \link fvOption.H \endlink
-     - \link cellSetOption.H \endlink
+      - \link cellSetOption.H \endlink
+      - \link writeFile.H \endlink
+      - \link Function1.H \endlink
 
     The effectiveness table is described in terms of the primary and secondary
     mass flow rates.  For example, the table:
@@ -185,13 +191,15 @@ Usage
     \endverbatim
 
 Note
+  - Primary flow indicates the CFD flow region and
+    secondary flow the non-CFD-model region.
   - The table with name \c file should have the same units as the
-  secondary mass flow rate and kg/s for \c phi.
+    secondary mass flow rate and kg/s for \c phi.
   - \c faceZone is the faces at the inlet of the \c cellZone, it needs to be
-  created with flip map flags. It is used to integrate the net mass flow
+    created with flip map flags. It is used to integrate the net mass flow
-  rate into the heat exchanger.
+    rate into the heat exchanger.
   - \c primaryInletT sets the primary inlet temperature.  If not set, the
-  flux-averaged temperature is used.
+    flux-averaged temperature is used.
 
 SourceFiles
     effectivenessHeatExchangerSource.C
@@ -223,73 +231,66 @@ class effectivenessHeatExchangerSource
     public fv::cellSetOption,
     public functionObjects::writeFile
 {
-protected:
+    // Private Data
 
-    // Protected Data
+        //- Flag to use a user-specified primary flow inlet temperature
-
-        //- Secondary flow mass rate [kg/s]
-        scalar secondaryMassFlowRate_;
-
-        //- Inlet secondary temperature [K]
-        scalar secondaryInletT_;
-
-        //- Secondary specific heat capacity [J/kg/K]
-        autoPtr<Function1<scalar>> secondaryCpPtr_;
-
-        //- Primary air temperature at the heat exchanger inlet [K]
-        scalar primaryInletT_;
-
-        //- Flag to use a user-specified primary inlet temperature
         bool userPrimaryInletT_;
 
         //- Flag to use target heat rejection
         bool targetQdotActive_;
 
-        //- Target heat rejection
+        //- Secondary flow specific heat capacity [J/kg/K]
-        scalar targetQdot_;
+        autoPtr<Function1<scalar>> secondaryCpPtr_;
+
+        //- 2D effectiveness table = function of primary and secondary
+        //- mass flow rates [kg/s]
+        autoPtr<interpolation2DTable<scalar>> eTable_;
 
         //- Target heat rejection calculation interval
         label targetQdotCalcInterval_;
 
+        //- Secondary flow mass rate [kg/s]
+        scalar secondaryMassFlowRate_;
+
+        //- Secondary flow inlet temperature [K]
+        scalar secondaryInletT_;
+
+        //- Primary flow temperature at the heat exchanger inlet [K]
+        scalar primaryInletT_;
+
+        //- Target heat rejection
+        scalar targetQdot_;
+
         //- Target heat rejection temperature under-relaxation coefficient
         scalar targetQdotRelax_;
 
-        //- 2D look up table efficiency = function of primary and secondary
+        //- Name of operand velocity field
-        //- mass flow rates [kg/s]
-        autoPtr<interpolation2DTable<scalar>> eTable_;
-
-        //- Name of velocity field; default = U
         word UName_;
 
-        //- Name of temperature field; default = T
+        //- Name of operand temperature field
         word TName_;
 
-        //- Name of the flux
+        //- Name of operand flux field
         word phiName_;
 
-        //- Name of the faceZone at the heat exchange inlet
+        //- Name of the faceZone at the heat exchanger inlet
         word faceZoneName_;
 
-         //- Local list of face IDs
+        //- Local list of face IDs
         labelList faceId_;
 
-        //- Local list of patch ID per face
+        //- Local list of patch IDs per face
         labelList facePatchId_;
 
         //- List of +1/-1 representing face flip map (1 use as is, -1 negate)
         labelList faceSign_;
 
 
-private:
-
     // Private Member Functions
 
         //- Initialise heat exchanger source model
         void initialise();
 
-        //- Calculate total area of faceZone across processors
-        void calculateTotalArea(scalar& area);
-
         //- Output file header information
         virtual void writeFileHeader(Ostream& os);
 
@@ -347,7 +348,7 @@ public:
         );
 
 
-        // IO
+        // I-O
 
             //- Read dictionary
             virtual bool read(const dictionary& dict);