ENC: sixDoFRigidBodyMotion. Adding tabulatedAxialAngularSpring restraint.

src/postProcessing/functionObjects/forces/Make/files

@@ -18,6 +18,7 @@ $(sDoFRBMR)/sixDoFRigidBodyMotionRestraint/newSixDoFRigidBodyMotionRestraint.C
 $(sDoFRBMR)/linearAxialAngularSpring/linearAxialAngularSpring.C
 $(sDoFRBMR)/linearSpring/linearSpring.C
 $(sDoFRBMR)/sphericalAngularSpring/sphericalAngularSpring.C
+$(sDoFRBMR)/tabulatedAxialAngularSpring/tabulatedAxialAngularSpring.C
 
 sDoFRBMC = $(sDoFRBM)/sixDoFRigidBodyMotionConstraint
 

src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionRestraint/tabulatedAxialAngularSpring/tabulatedAxialAngularSpring.C

@@ -0,0 +1,230 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 1991-2009 OpenCFD Ltd.
+     \\/     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 2 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, write to the Free Software Foundation,
+    Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+\*---------------------------------------------------------------------------*/
+
+#include "tabulatedAxialAngularSpring.H"
+#include "addToRunTimeSelectionTable.H"
+#include "sixDoFRigidBodyMotion.H"
+#include "transform.H"
+#include "unitConversion.H"
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+
+namespace Foam
+{
+namespace sixDoFRigidBodyMotionRestraints
+{
+    defineTypeNameAndDebug(tabulatedAxialAngularSpring, 0);
+    addToRunTimeSelectionTable
+    (
+        sixDoFRigidBodyMotionRestraint,
+        tabulatedAxialAngularSpring,
+        dictionary
+    );
+};
+};
+
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+Foam::sixDoFRigidBodyMotionRestraints::tabulatedAxialAngularSpring::
+tabulatedAxialAngularSpring
+(
+    const dictionary& sDoFRBMRDict
+)
+:
+    sixDoFRigidBodyMotionRestraint(sDoFRBMRDict),
+    refQ_(),
+    axis_(),
+    stiffness_(),
+    convertToDegrees_(),
+    damping_()
+{
+    read(sDoFRBMRDict);
+}
+
+
+// * * * * * * * * * * * * * * * * Destructors * * * * * * * * * * * * * * * //
+
+Foam::sixDoFRigidBodyMotionRestraints::tabulatedAxialAngularSpring::
+~tabulatedAxialAngularSpring()
+{}
+
+
+// * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * * //
+
+void
+Foam::sixDoFRigidBodyMotionRestraints::tabulatedAxialAngularSpring::restrain
+(
+    const sixDoFRigidBodyMotion& motion,
+    vector& restraintPosition,
+    vector& restraintForce,
+    vector& restraintMoment
+) const
+{
+    vector refDir = rotationTensor(vector(1, 0 ,0), axis_) & vector(0, 1, 0);
+
+    vector oldDir = refQ_ & refDir;
+
+    vector newDir = motion.currentOrientation(refDir);
+
+    if (mag(oldDir & axis_) > 0.95 || mag(newDir & axis_) > 0.95)
+    {
+        // Directions getting close to the axis, change reference
+
+        refDir = rotationTensor(vector(1, 0 ,0), axis_) & vector(0, 0, 1);
+
+        vector oldDir = refQ_ & refDir;
+
+        vector newDir = motion.currentOrientation(refDir);
+    }
+
+    // Removing any axis component from oldDir and newDir and normalising
+    oldDir -= (axis_ & oldDir)*axis_;
+    oldDir /= mag(oldDir);
+
+    newDir -= (axis_ & newDir)*axis_;
+    newDir /= mag(newDir);
+
+    scalar theta = mag(acos(oldDir & newDir));
+
+    // Temporary axis with sign information.
+    vector a = (oldDir ^ newDir);
+
+    // Remove any component that is not along axis that may creep in
+    a = (a & axis_)*axis_;
+
+    scalar magA = mag(a);
+
+    if (magA > VSMALL)
+    {
+        a /= magA;
+    }
+    else
+    {
+        a = vector::zero;
+    }
+
+    scalar stiffness;
+
+    if (convertToDegrees_)
+    {
+        stiffness = stiffness_(radToDeg(theta));
+    }
+    else
+    {
+        stiffness = stiffness_(theta);
+    }
+
+    // Damping of along axis angular velocity only
+    restraintMoment = -stiffness*theta*a - damping_*(motion.omega() & a)*a;
+
+    restraintForce = vector::zero;
+
+    // Not needed to be altered as restraintForce is zero, but set to
+    // centreOfMass to be sure of no spurious moment
+    restraintPosition = motion.centreOfMass();
+}
+
+
+bool Foam::sixDoFRigidBodyMotionRestraints::tabulatedAxialAngularSpring::read
+(
+    const dictionary& sDoFRBMRDict
+)
+{
+    sixDoFRigidBodyMotionRestraint::read(sDoFRBMRDict);
+
+    refQ_ = sDoFRBMRCoeffs_.lookupOrDefault<tensor>("referenceOrientation", I);
+
+    if (mag(mag(refQ_) - sqrt(3.0)) > 1e-9)
+    {
+        FatalErrorIn
+        (
+            "Foam::sixDoFRigidBodyMotionRestraints::"
+            "tabulatedAxialAngularSpring::read"
+            "("
+                "const dictionary& sDoFRBMRDict"
+            ")"
+        )
+            << "referenceOrientation " << refQ_ << " is not a rotation tensor. "
+            << "mag(referenceOrientation) - sqrt(3) = "
+            << mag(refQ_) - sqrt(3.0) << nl
+            << exit(FatalError);
+    }
+
+    axis_ = sDoFRBMRCoeffs_.lookup("axis");
+
+    scalar magAxis(mag(axis_));
+
+    if (magAxis > VSMALL)
+    {
+        axis_ /= magAxis;
+    }
+    else
+    {
+        FatalErrorIn
+        (
+            "Foam::sixDoFRigidBodyMotionRestraints::"
+            "tabulatedAxialAngularSpring::read"
+            "("
+                "const dictionary& sDoFRBMCDict"
+            ")"
+        )
+            << "axis has zero length"
+            << abort(FatalError);
+    }
+
+    stiffness_ = interpolationTable<scalar>(sDoFRBMRCoeffs_);
+
+    word angleFormat = sDoFRBMRCoeffs_.lookup("angleFormat");
+
+    if (angleFormat == "degrees" || angleFormat == "degree")
+    {
+        convertToDegrees_ = true;
+    }
+    else if (angleFormat == "radians" || angleFormat == "radian")
+    {
+        convertToDegrees_ = false;
+    }
+    else
+    {
+        FatalErrorIn
+        (
+            "Foam::sixDoFRigidBodyMotionRestraints::"
+            "tabulatedAxialAngularSpring::read"
+            "("
+                "const dictionary& sDoFRBMCDict"
+            ")"
+        )
+            << "angleFormat must be degree, degrees, radian or radians"
+            << abort(FatalError);
+    }
+
+    sDoFRBMRCoeffs_.lookup("damping") >> damping_;
+
+    return true;
+}
+
+// ************************************************************************* //

src/postProcessing/functionObjects/forces/pointPatchFields/derived/sixDoFRigidBodyMotion/sixDoFRigidBodyMotionRestraint/tabulatedAxialAngularSpring/tabulatedAxialAngularSpring.H

@@ -0,0 +1,137 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 1991-2009 OpenCFD Ltd.
+     \\/     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 2 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, write to the Free Software Foundation,
+    Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+
+Class
+    Foam::sixDoFRigidBodyMotionRestraints::tabulatedAxialAngularSpring
+
+Description
+    sixDoFRigidBodyMotionRestraints model.  Axial angular spring with stiffness
+    values drawn from an interpolation table.  Linear damping.
+
+SourceFiles
+    tabulatedAxialAngularSpring.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef tabulatedAxialAngularSpring_H
+#define tabulatedAxialAngularSpring_H
+
+#include "sixDoFRigidBodyMotionRestraint.H"
+#include "point.H"
+#include "tensor.H"
+#include "interpolationTable.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+namespace sixDoFRigidBodyMotionRestraints
+{
+
+/*---------------------------------------------------------------------------*\
+                  Class tabulatedAxialAngularSpring Declaration
+\*---------------------------------------------------------------------------*/
+
+class tabulatedAxialAngularSpring
+:
+    public sixDoFRigidBodyMotionRestraint
+{
+    // Private data
+
+        //- Reference orientation where there is no moment
+        tensor refQ_;
+
+        //- Global unit axis around which the motion is sprung
+        vector axis_;
+
+        //- Spring stiffness coefficient interpolation table (Nm/rad
+        //  or Nm/deg, depending on angleFormat)
+        interpolationTable<scalar> stiffness_;
+
+        //- Boolean stating whether the angle around the axis needs to
+        //  be converted to degrees before asking the
+        //  interpolationTable for a value
+        bool convertToDegrees_;
+
+        //- Damping coefficient (Nms/rad)
+        scalar damping_;
+
+
+public:
+
+    //- Runtime type information
+    TypeName("tabulatedAxialAngularSpring");
+
+
+    // Constructors
+
+        //- Construct from components
+        tabulatedAxialAngularSpring
+        (
+            const dictionary& sDoFRBMRDict
+        );
+
+        //- Construct and return a clone
+        virtual autoPtr<sixDoFRigidBodyMotionRestraint> clone() const
+        {
+            return autoPtr<sixDoFRigidBodyMotionRestraint>
+            (
+                new tabulatedAxialAngularSpring(*this)
+            );
+        }
+
+
+    // Destructor
+
+        virtual ~tabulatedAxialAngularSpring();
+
+
+    // Member Functions
+
+        //- Calculate the restraint position, force and moment.
+        //  Global reference frame vectors.
+        virtual void restrain
+        (
+            const sixDoFRigidBodyMotion& motion,
+            vector& restraintPosition,
+            vector& restraintForce,
+            vector& restraintMoment
+        ) const;
+
+        //- Update properties from given dictionary
+        virtual bool read(const dictionary& sDoFRBMRCoeff);
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace solidBodyMotionFunctions
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //