Periodic oscillation translational constraint

src/ODE/Make/files

@@ -21,6 +21,7 @@ $(sixDOF)/constraints/rotationalConstraints/constantAngularAcceleration/constant
 
 $(sixDOF)/constraints/translationalConstraints/translationalConstraint/translationalConstraint.C
 $(sixDOF)/constraints/translationalConstraints/constantTranslationalAcceleration/constantTranslationalAcceleration.C
+$(sixDOF)/constraints/translationalConstraints/periodicOscillation/periodicOscillation.C
 
 $(sixDOF)/sixDOFODE/sixDOFODE.C
 $(sixDOF)/sixDOFODE/newSixDOFODE.C

src/ODE/sixDOF/constraints/rotationalConstraints/constantAngularAcceleration/constantAngularAcceleration.C

@@ -51,7 +51,26 @@ Foam::constantAngularAcceleration::constantAngularAcceleration
     dir_(dict.lookup("constraintDirection")),
     alpha_(readScalar(dict.lookup("angularAcceleration"))),
     inGlobal_(dict.lookup("inGlobalCoordinateSystem"))
-{}
+{
+    // Rescale direction
+    if (mag(dir_) < SMALL)
+    {
+        FatalErrorIn
+        (
+            "Foam::constantTranslationalAcceleration::"
+            "constantTranslationalAcceleration"
+            "\n("
+            "\n    const word& name,"
+            "\n    const dictionary& dict"
+            "\n)"
+        )   << "Zero direction specified. This is not allowed."
+            << exit(FatalError);
+    }
+    else
+    {
+        dir_ /= mag(dir_);
+    }
+}
 
 
 Foam::autoPtr<Foam::rotationalConstraint>

src/ODE/sixDOF/constraints/rotationalConstraints/constantAngularAcceleration/constantAngularAcceleration.H

@@ -59,7 +59,7 @@ class constantAngularAcceleration
     // Private data
 
         //- Direction of the constraint (unit vector)
-        const vector dir_;
+        vector dir_;
 
         //- Constant value of angular acceleration
         const scalar alpha_;

src/ODE/sixDOF/constraints/translationalConstraints/constantTranslationalAcceleration/constantTranslationalAcceleration.C

@@ -50,7 +50,26 @@ Foam::constantTranslationalAcceleration::constantTranslationalAcceleration
     translationalConstraint(name, dict),
     dir_(dict.lookup("constraintDirection")),
     a_(readScalar(dict.lookup("translationalAcceleration")))
-{}
+{
+    // Rescale direction
+    if (mag(dir_) < SMALL)
+    {
+        FatalErrorIn
+        (
+            "Foam::constantTranslationalAcceleration::"
+            "constantTranslationalAcceleration"
+            "\n("
+            "\n    const word& name,"
+            "\n    const dictionary& dict"
+            "\n)"
+        )   << "Zero direction specified. This is not allowed."
+            << exit(FatalError);
+    }
+    else
+    {
+        dir_ /= mag(dir_);
+    }
+}
 
 
 Foam::autoPtr<Foam::translationalConstraint>

src/ODE/sixDOF/constraints/translationalConstraints/constantTranslationalAcceleration/constantTranslationalAcceleration.H

@@ -59,7 +59,7 @@ class constantTranslationalAcceleration
     // Private data
 
         //- Direction of the constraint (unit vector)
-        const vector dir_;
+        vector dir_;
 
         //- Constant value of the translational acceleration
         const scalar a_;

src/ODE/sixDOF/constraints/translationalConstraints/periodicOscillation/periodicOscillation.C

@@ -0,0 +1,136 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | foam-extend: Open Source CFD
+   \\    /   O peration     | Version:     4.0
+    \\  /    A nd           | Web:         http://www.foam-extend.org
+     \\/     M anipulation  | For copyright notice see file Copyright
+-------------------------------------------------------------------------------
+License
+    This file is part of foam-extend.
+
+    foam-extend 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.
+
+    foam-extend 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 foam-extend.  If not, see <http://www.gnu.org/licenses/>.
+
+\*---------------------------------------------------------------------------*/
+
+#include "periodicOscillation.H"
+#include "addToRunTimeSelectionTable.H"
+#include "mathematicalConstants.H"
+
+// * * * * * * * * * * * * * * Static Data Members * * * * * * * * * * * * * //
+
+namespace Foam
+{
+    defineTypeNameAndDebug(periodicOscillation, 0);
+    addToRunTimeSelectionTable
+    (
+        translationalConstraint,
+        periodicOscillation,
+        word
+    );
+}
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+Foam::periodicOscillation::periodicOscillation
+(
+    const word& name,
+    const dictionary& dict
+)
+:
+    translationalConstraint(name, dict),
+    dir_(dict.lookup("direction")),
+    a_(readScalar(dict.lookup("motionAmplitude"))),
+    period_(readScalar(dict.lookup("period"))),
+    omega_(mathematicalConstant::twoPi/period_),
+    phi_(readScalar(dict.lookup("phaseShift"))*mathematicalConstant::pi/180.0)
+{
+    // Rescale direction
+    if (mag(dir_) < SMALL)
+    {
+        FatalErrorIn
+        (
+            "Foam::periodicOscillation::periodicOscillation"
+            "\n("
+            "\n    const word& name,"
+            "\n    const dictionary& dict"
+            "\n)"
+        )   << "Zero direction specified. This is not allowed."
+            << exit(FatalError);
+    }
+    else
+    {
+        dir_ /= mag(dir_);
+    }
+}
+
+
+Foam::autoPtr<Foam::translationalConstraint>
+Foam::periodicOscillation::clone() const
+{
+    return autoPtr<translationalConstraint>
+    (
+        new periodicOscillation(*this)
+    );
+}
+
+
+// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
+
+Foam::periodicOscillation::~periodicOscillation()
+{}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+Foam::vector Foam::periodicOscillation::matrixContribution
+(
+    const scalar,
+    const tensor&,
+    const vector&,
+    const vector&
+) const
+{
+    return dir_;
+}
+
+
+Foam::scalar Foam::periodicOscillation::sourceContribution
+(
+    const scalar t,
+    const tensor&,
+    const vector&,
+    const vector&
+) const
+{
+    return -a_*sqr(omega_)*(sin(omega_*t + phi_));
+}
+
+
+void Foam::periodicOscillation::write(Ostream& os) const
+{
+    os.writeKeyword("type") << tab << type()
+        << token::END_STATEMENT << nl << nl;
+
+    os.writeKeyword("direction") << tab << dir_
+       << token::END_STATEMENT << nl;
+    os.writeKeyword("motionAmplitude") << tab << a_
+       << token::END_STATEMENT << nl;
+    os.writeKeyword("period") << tab << period_
+      << token::END_STATEMENT << nl;
+    os.writeKeyword("phaseShift") << tab
+      << phi_*180.0/mathematicalConstant::pi << token::END_STATEMENT << endl;
+}
+
+
+// ************************************************************************* //

src/ODE/sixDOF/constraints/translationalConstraints/periodicOscillation/periodicOscillation.H

@@ -0,0 +1,144 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | foam-extend: Open Source CFD
+   \\    /   O peration     | Version:     4.0
+    \\  /    A nd           | Web:         http://www.foam-extend.org
+     \\/     M anipulation  | For copyright notice see file Copyright
+-------------------------------------------------------------------------------
+License
+    This file is part of foam-extend.
+
+    foam-extend 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.
+
+    foam-extend 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 foam-extend.  If not, see <http://www.gnu.org/licenses/>.
+
+Class
+    Foam::periodicOscillation
+
+Description
+    Periodic translational motion given by:
+
+    g(vDot, t) = vDot + a*omega^2*sin(omega*t + phi) = 0,
+
+    where a is the amplitude of oscillation, omega radial frequency and phi is
+    the phase shift.
+
+Author
+    Viktor Pandza, FSB Zagreb.  All rights reserved.
+    Vuko Vukcevic, FSB Zagreb.  All rights reserved.
+
+SourceFiles
+    periodicOscillation.C
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef periodicOscillation_H
+#define periodicOscillation_H
+
+#include "translationalConstraint.H"
+#include "OFstream.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+
+/*---------------------------------------------------------------------------*\
+                     Class periodicOscillation Declaration
+\*---------------------------------------------------------------------------*/
+
+class periodicOscillation
+:
+    public translationalConstraint
+{
+    // Private data
+
+        //- Direction
+        vector dir_;
+    
+        //- Amplitude of the motion
+        const scalar a_;
+
+        //- Period of the motion
+        const scalar period_;
+    
+        //- Radian frequency of the motion
+        const scalar omega_;
+
+        //- Phase shift (in degrees)
+        const scalar phi_;
+
+
+public:
+
+    //- Runtime type information
+    TypeName("periodicOscillation");
+
+
+    // Constructors
+
+        //- Construct from dictionary
+        periodicOscillation
+        (
+            const word& name,
+            const dictionary& dict
+        );
+
+        //- Construct and return a clone
+        virtual autoPtr<translationalConstraint> clone() const;
+
+
+    // Destructor
+
+        virtual ~periodicOscillation();
+
+
+    // Member Functions
+
+        // Constraint specific functions
+
+            //- Return matrix contribution defined by constraint, f(t)
+            virtual vector matrixContribution
+            (
+                const scalar,
+                const tensor&,
+                const vector&,
+                const vector&
+            ) const;
+
+            //- Return source contribution defined by constraint, a(t)
+            virtual scalar sourceContribution
+            (
+                const scalar t,
+                const tensor&,
+                const vector&,
+                const vector& 
+            ) const;
+
+
+
+    // I-O Functions
+
+        //- Virtual write function
+        virtual void write(Ostream& os) const;
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //