rigidBodyMeshMotionSolver: experimental nDoF mesh-motion solver supporting the displacement-based elliptic solvers

Specification for the tutorials/multiphase/interDyMFoam/ras/floatingObject case:

dynamicFvMesh       dynamicMotionSolverFvMesh;

motionSolverLibs   ("librigidBodyMeshMotion.so" "libfvMotionSolvers.so");

solver             rigidBodyMotionSolver;

rigidBodyMotionSolverCoeffs
{
    report          on;

    meshSolver
    {
        solver displacementLaplacian;

        displacementLaplacianCoeffs
        {
            diffusivity inverseDistance (floatingObject);
        }
    }
.
.
.

src/rigidBodyDynamics/rigidBodyMotion/rigidBodyMotion.C

@@ -178,6 +178,28 @@ void Foam::RBD::rigidBodyMotion::status(const label bodyID) const
 }
 
 
+Foam::tmp<Foam::pointField> Foam::RBD::rigidBodyMotion::transformPoints
+(
+    const label bodyID,
+    const pointField& initialPoints
+) const
+{
+    // Calculate the transform from the initial state in the global frame
+    // to the current state in the global frame
+    spatialTransform X(X0(bodyID).inv() & X00(bodyID));
+
+    tmp<pointField> tpoints(new pointField(initialPoints.size()));
+    pointField& points = tpoints.ref();
+
+    forAll(points, i)
+    {
+        points[i] = X.transformPoint(initialPoints[i]);
+    }
+
+    return tpoints;
+}
+
+
 Foam::tmp<Foam::pointField> Foam::RBD::rigidBodyMotion::transformPoints
 (
     const label bodyID,

src/rigidBodyDynamics/rigidBodyMotion/rigidBodyMotion.H

@@ -183,6 +183,14 @@ public:
 
         // Transformations
 
+            //- Transform the given initial pointField of the specified body
+            //  to correspond to the current motion state
+            tmp<pointField> transformPoints
+            (
+                const label bodyID,
+                const pointField& initialPoints
+            ) const;
+
             //- Transform the given initial pointField of the specified body
             //  to correspond to the current motion state scaled using
             //  'slerp' interpolation

src/rigidBodyMeshMotion/Make/files

@@ -1,3 +1,4 @@
-rigidBodyMeshMotion.C
+rigidBodyMeshMotion/rigidBodyMeshMotion.C
+rigidBodyMeshMotionSolver/rigidBodyMeshMotionSolver.C
 
 LIB = $(FOAM_LIBBIN)/librigidBodyMeshMotion

src/rigidBodyMeshMotion/rigidBodyMeshMotionSolver/rigidBodyMeshMotionSolver.C

@@ -0,0 +1,334 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2016 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/>.
+
+\*---------------------------------------------------------------------------*/
+
+#include "rigidBodyMeshMotionSolver.H"
+#include "addToRunTimeSelectionTable.H"
+#include "polyMesh.H"
+#include "pointPatchDist.H"
+#include "pointConstraints.H"
+#include "uniformDimensionedFields.H"
+#include "forces.H"
+#include "mathematicalConstants.H"
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+
+namespace Foam
+{
+    defineTypeNameAndDebug(rigidBodyMeshMotionSolver, 0);
+
+    addToRunTimeSelectionTable
+    (
+        motionSolver,
+        rigidBodyMeshMotionSolver,
+        dictionary
+    );
+}
+
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+Foam::rigidBodyMeshMotionSolver::bodyMesh::bodyMesh
+(
+    const polyMesh& mesh,
+    const word& name,
+    const label bodyID,
+    const dictionary& dict
+)
+:
+    name_(name),
+    bodyID_(bodyID),
+    patches_(wordReList(dict.lookup("patches"))),
+    patchSet_(mesh.boundaryMesh().patchSet(patches_))
+{}
+
+
+Foam::rigidBodyMeshMotionSolver::rigidBodyMeshMotionSolver
+(
+    const polyMesh& mesh,
+    const IOdictionary& dict
+)
+:
+    motionSolver(mesh, dict, typeName),
+    model_
+    (
+        coeffDict(),
+        IOobject
+        (
+            "rigidBodyMotionState",
+            mesh.time().timeName(),
+            "uniform",
+            mesh
+        ).headerOk()
+      ? IOdictionary
+        (
+            IOobject
+            (
+                "rigidBodyMotionState",
+                mesh.time().timeName(),
+                "uniform",
+                mesh,
+                IOobject::READ_IF_PRESENT,
+                IOobject::NO_WRITE,
+                false
+            )
+        )
+      : coeffDict()
+    ),
+    test_(coeffDict().lookupOrDefault<Switch>("test", false)),
+    rhoInf_(1.0),
+    rhoName_(coeffDict().lookupOrDefault<word>("rho", "rho")),
+    curTimeIndex_(-1),
+    meshSolverPtr_
+    (
+        motionSolver::New
+        (
+            mesh,
+            IOdictionary
+            (
+                IOobject
+                (
+                    "rigidBodyMotionSolver:meshSolver",
+                    mesh.time().constant(),
+                    mesh
+                ),
+                coeffDict().subDict("meshSolver")
+            )
+        )
+    ),
+    meshSolver_(refCast<displacementMotionSolver>(meshSolverPtr_()))
+{
+    if (rhoName_ == "rhoInf")
+    {
+        rhoInf_ = readScalar(coeffDict().lookup("rhoInf"));
+    }
+
+    const dictionary& bodiesDict = coeffDict().subDict("bodies");
+
+    forAllConstIter(IDLList<entry>, bodiesDict, iter)
+    {
+        const dictionary& bodyDict = iter().dict();
+
+        if (bodyDict.found("patches"))
+        {
+            const label bodyID = model_.bodyID(iter().keyword());
+
+            if (bodyID == -1)
+            {
+                FatalErrorInFunction
+                    << "Body " << iter().keyword()
+                    << " has been merged with another body"
+                       " and cannot be assigned a set of patches"
+                    << exit(FatalError);
+            }
+
+            bodyMeshes_.append
+            (
+                new bodyMesh
+                (
+                    mesh,
+                    iter().keyword(),
+                    bodyID,
+                    bodyDict
+                )
+            );
+        }
+    }
+}
+
+
+// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
+
+Foam::rigidBodyMeshMotionSolver::~rigidBodyMeshMotionSolver()
+{}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+Foam::tmp<Foam::pointField>
+Foam::rigidBodyMeshMotionSolver::curPoints() const
+{
+    return meshSolverPtr_->curPoints();
+}
+
+
+void Foam::rigidBodyMeshMotionSolver::solve()
+{
+    const Time& t = mesh().time();
+
+    if (mesh().nPoints() != meshSolver_.points0().size())
+    {
+        FatalErrorInFunction
+            << "The number of points in the mesh seems to have changed." << endl
+            << "In constant/polyMesh there are " << meshSolver_.points0().size()
+            << " points; in the current mesh there are " << mesh().nPoints()
+            << " points." << exit(FatalError);
+    }
+
+    // Store the motion state at the beginning of the time-step
+    if (curTimeIndex_ != this->db().time().timeIndex())
+    {
+        model_.newTime();
+        curTimeIndex_ = this->db().time().timeIndex();
+    }
+
+    if (db().foundObject<uniformDimensionedVectorField>("g"))
+    {
+        model_.g() =
+            db().lookupObject<uniformDimensionedVectorField>("g").value();
+    }
+
+    if (test_)
+    {
+        label nIter(readLabel(coeffDict().lookup("nIter")));
+
+        for (label i=0; i<nIter; i++)
+        {
+            model_.solve
+            (
+                t.deltaTValue(),
+                scalarField(model_.nDoF(), Zero),
+                Field<spatialVector>(model_.nBodies(), Zero)
+            );
+        }
+    }
+    else
+    {
+        Field<spatialVector> fx(model_.nBodies(), Zero);
+
+        forAll(bodyMeshes_, bi)
+        {
+            const label bodyID = bodyMeshes_[bi].bodyID_;
+
+            dictionary forcesDict;
+            forcesDict.add("type", functionObjects::forces::typeName);
+            forcesDict.add("patches", bodyMeshes_[bi].patches_);
+            forcesDict.add("rhoInf", rhoInf_);
+            forcesDict.add("rho", rhoName_);
+            forcesDict.add("CofR", vector::zero);
+
+            functionObjects::forces f("forces", db(), forcesDict);
+            f.calcForcesMoment();
+
+            fx[bodyID] = spatialVector(f.momentEff(), f.forceEff());
+        }
+
+        model_.solve
+        (
+            t.deltaTValue(),
+            scalarField(model_.nDoF(), Zero),
+            fx
+        );
+    }
+
+    if (Pstream::master() && model_.report())
+    {
+        forAll(bodyMeshes_, bi)
+        {
+            model_.status(bodyMeshes_[bi].bodyID_);
+        }
+    }
+
+    // Update the displacements
+    forAll(bodyMeshes_, bi)
+    {
+        forAllConstIter(labelHashSet, bodyMeshes_[bi].patchSet_, iter)
+        {
+            label patchi = iter.key();
+
+            pointField patchPoints0
+            (
+                meshSolver_.pointDisplacement().boundaryField()[patchi]
+               .patchInternalField(meshSolver_.points0())
+            );
+
+            meshSolver_.pointDisplacement().boundaryFieldRef()[patchi] ==
+            (
+                model_.transformPoints
+                (
+                    bodyMeshes_[bi].bodyID_,
+                    patchPoints0
+                ) - patchPoints0
+            )();
+        }
+    }
+
+    meshSolverPtr_->solve();
+}
+
+
+bool Foam::rigidBodyMeshMotionSolver::writeObject
+(
+    IOstream::streamFormat fmt,
+    IOstream::versionNumber ver,
+    IOstream::compressionType cmp
+) const
+{
+    IOdictionary dict
+    (
+        IOobject
+        (
+            "rigidBodyMotionState",
+            mesh().time().timeName(),
+            "uniform",
+            mesh(),
+            IOobject::NO_READ,
+            IOobject::NO_WRITE,
+            false
+        )
+    );
+
+    model_.state().write(dict);
+    return dict.regIOobject::write();
+}
+
+
+bool Foam::rigidBodyMeshMotionSolver::read()
+{
+    if (motionSolver::read())
+    {
+        model_.read(coeffDict());
+
+        return true;
+    }
+    else
+    {
+        return false;
+    }
+}
+
+
+void Foam::rigidBodyMeshMotionSolver::movePoints(const pointField& points)
+{
+    meshSolverPtr_->movePoints(points);
+}
+
+
+void Foam::rigidBodyMeshMotionSolver::updateMesh(const mapPolyMesh& mpm)
+{
+    meshSolverPtr_->updateMesh(mpm);
+}
+
+
+// ************************************************************************* //

src/rigidBodyMeshMotion/rigidBodyMeshMotionSolver/rigidBodyMeshMotionSolver.H

@@ -0,0 +1,184 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2016 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/>.
+
+Class
+    Foam::rigidBodyMeshMotionSolver
+
+Description
+    Rigid-body mesh motion solver for fvMesh.
+
+    Applies septernion interpolation of movement as function of distance to the
+    object surface.
+
+SourceFiles
+    rigidBodyMeshMotionSolver.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef rigidBodyMeshMotionSolver_H
+#define rigidBodyMeshMotionSolver_H
+
+#include "displacementMotionSolver.H"
+#include "rigidBodyMotion.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+/*---------------------------------------------------------------------------*\
+        Class rigidBodyMeshMotionSolver Declaration
+\*---------------------------------------------------------------------------*/
+
+class rigidBodyMeshMotionSolver
+:
+    public motionSolver
+{
+    //- Class containing the patches and point motion weighting for each body
+    class bodyMesh
+    {
+        //- Name of the body
+        const word name_;
+
+        //- ID of the body in the RBD::rigidBodyMotion
+        const label bodyID_;
+
+        //- List of mesh patches associated with this body
+        const wordReList patches_;
+
+        //- Patches to integrate forces
+        const labelHashSet patchSet_;
+
+
+    public:
+
+        friend class rigidBodyMeshMotionSolver;
+
+        bodyMesh
+        (
+            const polyMesh& mesh,
+            const word& name,
+            const label bodyID,
+            const dictionary& dict
+        );
+    };
+
+
+    // Private data
+
+        //- Rigid-body model
+        RBD::rigidBodyMotion model_;
+
+        //- List of the bodyMeshes containing the patches and point motion
+        //  weighting for each body
+        PtrList<bodyMesh> bodyMeshes_;
+
+        //- Switch for test-mode in which only the
+        //  gravitational body-force is applied
+        Switch test_;
+
+        //- Reference density required by the forces object for
+        //  incompressible calculations, required if rho == rhoInf
+        scalar rhoInf_;
+
+        //- Name of density field, optional unless used for an
+        //  incompressible simulation, when this needs to be specified
+        //  as rhoInf
+        word rhoName_;
+
+        //- Current time index (used for updating)
+        label curTimeIndex_;
+
+        autoPtr<motionSolver> meshSolverPtr_;
+
+        displacementMotionSolver& meshSolver_;
+
+
+    // Private Member Functions
+
+        //- Disallow default bitwise copy construct
+        rigidBodyMeshMotionSolver
+        (
+            const rigidBodyMeshMotionSolver&
+        );
+
+        //- Disallow default bitwise assignment
+        void operator=(const rigidBodyMeshMotionSolver&);
+
+
+public:
+
+    //- Runtime type information
+    TypeName("rigidBodyMotionSolver");
+
+
+    // Constructors
+
+        //- Construct from polyMesh and IOdictionary
+        rigidBodyMeshMotionSolver
+        (
+            const polyMesh&,
+            const IOdictionary& dict
+        );
+
+
+    //- Destructor
+    ~rigidBodyMeshMotionSolver();
+
+
+    // Member Functions
+
+        //- Return point location obtained from the current motion field
+        virtual tmp<pointField> curPoints() const;
+
+        //- Solve for motion
+        virtual void solve();
+
+        //- Write state using given format, version and compression
+        virtual bool writeObject
+        (
+            IOstream::streamFormat fmt,
+            IOstream::versionNumber ver,
+            IOstream::compressionType cmp
+        ) const;
+
+        //- Read dynamicMeshDict dictionary
+        virtual bool read();
+
+        //- Update local data for geometry changes
+        virtual void movePoints(const pointField&);
+
+        //-  Update local data for topology changes
+        virtual void updateMesh(const mapPolyMesh&);
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //