ENH: PatchInjectionModel - added new parcel initial velocity options

The parcel initial velocity can now be set using the new `velocityType`
entry, taking one of the following options:

- fixedValue   : (default) same as earlier versions, requires U0
- patchValue   : velocity set to seed patch face value
- zeroGradient : velocity set to seed patch face adjacent cell value

Example usage:

        model1
        {
            type            patchInjection;
            massTotal       1;
            SOI             0;
            parcelBasisType mass;
            patch           cylinder;
            duration        10;
            parcelsPerSecond 100;
            velocityType    patchValue;
            //velocityType    zeroGradient;
            //U0              (-10 0 0);
            flowRateProfile constant 1;
            sizeDistribution
            {
                type        normal;
                normalDistribution
                {
                    expectation 1e-3;
                    variance 1e-4;
                    minValue 1e-5;
                    maxValue 2e-3;
                }
            }
        }

See the new $FOAM_TUTORIALS/lagrangian/kinematicParcelFoam/spinningDisk tutorial

src/lagrangian/intermediate/submodels/Kinematic/InjectionModel/PatchInjection/PatchInjection.C

@@ -29,6 +29,17 @@ License
 #include "PatchInjection.H"
 #include "distributionModel.H"
 
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+
+template<class CloudType>
+const Foam::Enum<typename Foam::PatchInjection<CloudType>::velocityType>
+Foam::PatchInjection<CloudType>::velocityTypeNames_
+({
+    { vtFixedValue, "fixedValue" },
+    { vtPatchValue, "patchValue" },
+    { vtZeroGradient, "zeroGradient" },
+});
+
 // * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
 
 template<class CloudType>
@@ -46,7 +57,21 @@ Foam::PatchInjection<CloudType>::PatchInjection
     (
         this->coeffDict().getScalar("parcelsPerSecond")
     ),
-    U0_(this->coeffDict().lookup("U0")),
+    velocityType_
+    (
+        velocityTypeNames_.getOrDefault
+        (
+            "velocityType",
+            this->coeffDict(),
+            vtFixedValue
+        )
+    ),
+    U0_
+    (
+        velocityType_ == vtFixedValue
+      ? this->coeffDict().template get<vector>("U0")
+      : Zero
+    ),
     flowRateProfile_
     (
         Function1<scalar>::New
@@ -63,7 +88,9 @@ Foam::PatchInjection<CloudType>::PatchInjection
             this->coeffDict().subDict("sizeDistribution"),
             owner.rndGen()
         )
-    )
+    ),
+    currentParceli_(-1),
+    currentFacei_(-1)
 {
     // Convert from user time to reduce the number of time conversion calls
     const Time& time = owner.db().time();
@@ -87,16 +114,12 @@ Foam::PatchInjection<CloudType>::PatchInjection
     patchInjectionBase(im),
     duration_(im.duration_),
     parcelsPerSecond_(im.parcelsPerSecond_),
+    velocityType_(im.velocityType_),
     U0_(im.U0_),
     flowRateProfile_(im.flowRateProfile_.clone()),
-    sizeDistribution_(im.sizeDistribution_.clone())
-{}
-
-
-// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
-
-template<class CloudType>
-Foam::PatchInjection<CloudType>::~PatchInjection()
+    sizeDistribution_(im.sizeDistribution_.clone()),
+    currentParceli_(im.currentParceli_),
+    currentFacei_(im.currentFacei_)
 {}
 
 
@@ -167,16 +190,18 @@ Foam::scalar Foam::PatchInjection<CloudType>::volumeToInject
 template<class CloudType>
 void Foam::PatchInjection<CloudType>::setPositionAndCell
 (
-    const label,
-    const label,
-    const scalar,
+    const label parcelI,
+    const label nParcels,
+    const scalar time,
     vector& position,
     label& cellOwner,
     label& tetFacei,
     label& tetPti
 )
 {
-    patchInjectionBase::setPositionAndCell
+    currentParceli_ = parcelI;
+
+    currentFacei_ = patchInjectionBase::setPositionAndCell
     (
         this->owner().mesh(),
         this->owner().rndGen(),
@@ -191,16 +216,74 @@ void Foam::PatchInjection<CloudType>::setPositionAndCell
 template<class CloudType>
 void Foam::PatchInjection<CloudType>::setProperties
 (
-    const label,
-    const label,
-    const scalar,
+    const label parcelI,
+    const label nParcels,
+    const scalar time,
     typename CloudType::parcelType& parcel
 )
 {
-    // set particle velocity
-    parcel.U() = U0_;
+    // Set particle velocity
+    switch (velocityType_)
+    {
+        case vtFixedValue:
+        {
+            parcel.U() = U0_;
+            break;
+        }
+        case vtPatchValue:
+        {
+            if (parcelI != currentParceli_)
+            {
+                WarningInFunction
+                    << "Synchronisation problem: "
+                    << "attempting to set injected parcel " << parcelI
+                    << " properties using cached parcel " << currentParceli_
+                    << " properties" << endl;
+            }
 
-    // set particle diameter
+            const label patchFacei = currentFacei_;
+
+            if (patchFacei < 0)
+            {
+                FatalErrorInFunction
+                    << "Unable to set parcel velocity using patch value "
+                    << "due to missing face index: patchFacei=" << patchFacei
+                    << abort(FatalError);
+            }
+
+            const volVectorField& U = this->owner().U();
+            const label patchi = this->patchId_;
+            parcel.U() = U.boundaryField()[patchi][patchFacei];
+            break;
+        }
+        case vtZeroGradient:
+        {
+            const label celli = parcel.cell();
+
+            if (celli < 0)
+            {
+                FatalErrorInFunction
+                    << "Unable to set parcel velocity using zeroGradient "
+                    << "due to missing cell index"
+                    << abort(FatalError);
+            }
+
+            const volVectorField& U = this->owner().U();
+            parcel.U() = U[celli];
+            break;
+        }
+        default:
+        {
+            FatalErrorInFunction
+                << "Unhandled velocityType "
+                << velocityTypeNames_[velocityType_]
+                << ". Available options are:"
+                << velocityTypeNames_.sortedToc()
+                << abort(FatalError);
+        }
+    }
+
+    // Set particle diameter
     parcel.d() = sizeDistribution_->sample();
 }
 

src/lagrangian/intermediate/submodels/Kinematic/InjectionModel/PatchInjection/PatchInjection.H

@@ -72,6 +72,24 @@ class PatchInjection
     public InjectionModel<CloudType>,
     public patchInjectionBase
 {
+public:
+
+    // Public Data Types
+
+        //- Velocity type enumeration
+        enum velocityType
+        {
+            vtFixedValue,   //!< User supplied fixed value
+            vtPatchValue,   //!< Patch face values
+            vtZeroGradient  //!< Patch internal cell values
+        };
+
+        //- Velocity type names
+        static const Enum<velocityType> velocityTypeNames_;
+
+
+private:
+
     // Private data
 
         //- Injection duration [s]
@@ -80,7 +98,11 @@ class PatchInjection
         //- Number of parcels to introduce per second []
         const label parcelsPerSecond_;
 
+        //- Velocity type
+        const velocityType velocityType_;
+
         //- Initial parcel velocity [m/s]
+        //  Note: Only used for vtFixedValue
         const vector U0_;
 
         //- Flow rate profile relative to SOI []
@@ -89,6 +111,12 @@ class PatchInjection
         //- Parcel size distribution model
         const autoPtr<distributionModel> sizeDistribution_;
 
+        //- Current parcel being processed
+        label currentParceli_;
+
+        //- Current face being processed
+        label currentFacei_;
+
 
 public:
 
@@ -120,7 +148,7 @@ public:
 
 
     //- Destructor
-    virtual ~PatchInjection();
+    virtual ~PatchInjection() = default;
 
 
     // Member Functions

src/lagrangian/intermediate/submodels/Kinematic/InjectionModel/PatchInjection/patchInjectionBase.C

@@ -144,7 +144,7 @@ void Foam::patchInjectionBase::updateMesh(const polyMesh& mesh)
 }
 
 
-void Foam::patchInjectionBase::setPositionAndCell
+Foam::label Foam::patchInjectionBase::setPositionAndCell
 (
     const fvMesh& mesh,
     const scalar fraction01,
@@ -155,6 +155,8 @@ void Foam::patchInjectionBase::setPositionAndCell
     label& tetPti
 )
 {
+    label facei = -1;
+
     if (cellOwners_.size() > 0)
     {
         // Determine which processor to inject from
@@ -177,7 +179,7 @@ void Foam::patchInjectionBase::setPositionAndCell
             }
 
             // Set cellOwner
-            label facei = triToFace_[trii];
+            facei = triToFace_[trii];
             cellOwner = cellOwners_[facei];
 
             // Find random point in triangle
@@ -261,10 +263,12 @@ void Foam::patchInjectionBase::setPositionAndCell
         // Dummy position
         position = pTraits<vector>::max;
     }
+
+    return facei;
 }
 
 
-void Foam::patchInjectionBase::setPositionAndCell
+Foam::label Foam::patchInjectionBase::setPositionAndCell
 (
     const fvMesh& mesh,
     Random& rnd,
@@ -276,7 +280,7 @@ void Foam::patchInjectionBase::setPositionAndCell
 {
     scalar fraction01 = rnd.globalSample01<scalar>();
 
-    setPositionAndCell
+    return setPositionAndCell
     (
         mesh,
         fraction01,

src/lagrangian/intermediate/submodels/Kinematic/InjectionModel/PatchInjection/patchInjectionBase.H

@@ -118,7 +118,8 @@ public:
 
         //- Set the injection position and owner cell, tetFace and tetPt
         //  Supply the fraction used to determine the location on the patch
-        void setPositionAndCell
+        //  Returns the seed patch face index
+        label setPositionAndCell
         (
             const fvMesh& mesh,
             const scalar fraction01,
@@ -130,7 +131,8 @@ public:
         );
 
         //- Set the injection position and owner cell, tetFace and tetPt
-        virtual void setPositionAndCell
+        //  Returns the seed patch face index
+        virtual label setPositionAndCell
         (
             const fvMesh& mesh,
             Random& rnd,