From 439e2ca3fcebfde486b0795c9d25ee551c15b8b7 Mon Sep 17 00:00:00 2001
From: Armin Wehrfritz <armin.wehrfritz@aalto.fi>
Date: Fri, 30 Aug 2013 20:15:41 +0300
Subject: [PATCH] Add distorted sphere drag model

---
 .../makeBasicSprayParcelSubmodels.C                |    2 +
 .../DistortedSphereDrag/DistortedSphereDragForce.C |   95 +++++++++++++++
 .../DistortedSphereDrag/DistortedSphereDragForce.H |  128 ++++++++++++++++++++
 3 files changed, 225 insertions(+)
 create mode 100644 src/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.C
 create mode 100644 src/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.H

diff --git a/src/lagrangian/spray/parcels/derived/basicSprayParcel/makeBasicSprayParcelSubmodels.C b/src/lagrangian/spray/parcels/derived/basicSprayParcel/makeBasicSprayParcelSubmodels.C
index 01a480b..893319a 100644
--- a/src/lagrangian/spray/parcels/derived/basicSprayParcel/makeBasicSprayParcelSubmodels.C
+++ b/src/lagrangian/spray/parcels/derived/basicSprayParcel/makeBasicSprayParcelSubmodels.C
@@ -42,6 +42,7 @@ License
 #include "makeReactingParcelSurfaceFilmModels.H"
 
 // Spray
+#include "DistortedSphereDragForce.H"
 #include "makeSprayParcelAtomizationModels.H"
 #include "makeSprayParcelBreakupModels.H"
 #include "makeSprayParcelCollisionModels.H"
@@ -67,6 +68,7 @@ namespace Foam
     makeReactingParcelSurfaceFilmModels(basicSprayCloud);
 
     // Spray sub-models
+    makeParticleForceModelType(DistortedSphereDragForce, basicSprayCloud);
     makeSprayParcelAtomizationModels(basicSprayCloud);
     makeSprayParcelBreakupModels(basicSprayCloud);
     makeSprayParcelCollisionModels(basicSprayCloud);
diff --git a/src/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.C b/src/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.C
new file mode 100644
index 0000000..74d017f
--- /dev/null
+++ b/src/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.C
@@ -0,0 +1,95 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2011 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 "DistortedSphereDragForce.H"
+
+// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
+
+template<class CloudType>
+Foam::scalar Foam::DistortedSphereDragForce<CloudType>::CdRe(const scalar Re) const
+{
+    if (Re > 1000.0)
+    {
+        return 0.424*Re;
+    }
+    else
+    {
+        return 24.0*(1.0 + 1.0/6.0*pow(Re, 2.0/3.0));
+    }
+}
+
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+template<class CloudType>
+Foam::DistortedSphereDragForce<CloudType>::DistortedSphereDragForce
+(
+    CloudType& owner,
+    const fvMesh& mesh,
+    const dictionary& dict
+)
+:
+    ParticleForce<CloudType>(owner, mesh, dict, typeName, false)
+{}
+
+
+template<class CloudType>
+Foam::DistortedSphereDragForce<CloudType>::DistortedSphereDragForce
+(
+    const DistortedSphereDragForce<CloudType>& df
+)
+:
+    ParticleForce<CloudType>(df)
+{}
+
+
+// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
+
+template<class CloudType>
+Foam::DistortedSphereDragForce<CloudType>::~DistortedSphereDragForce()
+{}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+template<class CloudType>
+Foam::forceSuSp Foam::DistortedSphereDragForce<CloudType>::calcCoupled
+(
+    const typename CloudType::parcelType& p,
+    const scalar dt,
+    const scalar mass,
+    const scalar Re,
+    const scalar muc
+) const
+{
+    forceSuSp value(vector::zero, 0.0);
+
+    value.Sp() = mass*0.75*muc*CdRe(Re)*(1+2.632*p.y())/(p.rho()*sqr(p.d()));
+
+    return value;
+}
+
+
+// ************************************************************************* //
diff --git a/src/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.H b/src/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.H
new file mode 100644
index 0000000..69e5a36
--- /dev/null
+++ b/src/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.H
@@ -0,0 +1,128 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2011-2013 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::DistortedSphereDragForce
+
+Description
+    Drag model based on assumption of distorted spheres according to:
+
+    \verbatim
+        "Modeling Drop Drag Effects on Fuel Spray Impingement in Direct 
+         Injection Diesel Engines"
+
+        Z. Liu, T. Obokata and R. D. Reitz
+
+        SAE paper 970879
+    \endverbatim
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef DistortedSphereDragForce_H
+#define DistortedSphereDragForce_H
+
+#include "ParticleForce.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+/*---------------------------------------------------------------------------*\
+                       Class DistortedSphereDragForce Declaration
+\*---------------------------------------------------------------------------*/
+
+template<class CloudType>
+class DistortedSphereDragForce
+:
+    public ParticleForce<CloudType>
+{
+    // Private Member Functions
+
+        //- Drag coefficient multiplied by Reynolds number
+        scalar CdRe(const scalar Re) const;
+
+
+public:
+
+    //- Runtime type information
+    TypeName("distortedSphereDrag");
+
+
+    // Constructors
+
+        //- Construct from mesh
+        DistortedSphereDragForce
+        (
+            CloudType& owner,
+            const fvMesh& mesh,
+            const dictionary& dict
+        );
+
+        //- Construct copy
+        DistortedSphereDragForce(const DistortedSphereDragForce<CloudType>& df);
+
+        //- Construct and return a clone
+        virtual autoPtr<ParticleForce<CloudType> > clone() const
+        {
+            return autoPtr<ParticleForce<CloudType> >
+            (
+                new DistortedSphereDragForce<CloudType>(*this)
+            );
+        }
+
+
+    //- Destructor
+    virtual ~DistortedSphereDragForce();
+
+
+    // Member Functions
+
+        // Evaluation
+
+            //- Calculate the coupled force
+            virtual forceSuSp calcCoupled
+            (
+                const typename CloudType::parcelType& p,
+                const scalar dt,
+                const scalar mass,
+                const scalar Re,
+                const scalar muc
+            ) const;
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#ifdef NoRepository
+#   include "DistortedSphereDragForce.C"
+#endif
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //
-- 
1.7.10.4

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011 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 "DistortedSphereDragForce.H"

// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //

template<class CloudType>
Foam::scalar Foam::DistortedSphereDragForce<CloudType>::CdRe(const scalar Re) const
{
    if (Re > 1000.0)
    {
        return 0.424*Re;
    }
    else
    {
        return 24.0*(1.0 + 1.0/6.0*pow(Re, 2.0/3.0));
    }
}


// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //

template<class CloudType>
Foam::DistortedSphereDragForce<CloudType>::DistortedSphereDragForce
(
    CloudType& owner,
    const fvMesh& mesh,
    const dictionary& dict
)
:
    ParticleForce<CloudType>(owner, mesh, dict, typeName, false)
{}


template<class CloudType>
Foam::DistortedSphereDragForce<CloudType>::DistortedSphereDragForce
(
    const DistortedSphereDragForce<CloudType>& df
)
:
    ParticleForce<CloudType>(df)
{}


// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //

template<class CloudType>
Foam::DistortedSphereDragForce<CloudType>::~DistortedSphereDragForce()
{}


// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //

template<class CloudType>
Foam::forceSuSp Foam::DistortedSphereDragForce<CloudType>::calcCoupled
(
    const typename CloudType::parcelType& p,
    const scalar dt,
    const scalar mass,
    const scalar Re,
    const scalar muc
) const
{
    forceSuSp value(vector::zero, 0.0);

    value.Sp() = mass*0.75*muc*CdRe(Re)*(1+2.632*p.y())/(p.rho()*sqr(p.d()));

    return value;
}


// ************************************************************************* //

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011-2013 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::DistortedSphereDragForce

Description
    Drag model based on assumption of distorted spheres according to:

    \verbatim
        "Modeling Drop Drag Effects on Fuel Spray Impingement in Direct 
         Injection Diesel Engines"

        Z. Liu, T. Obokata and R. D. Reitz

        SAE paper 970879
    \endverbatim

\*---------------------------------------------------------------------------*/

#ifndef DistortedSphereDragForce_H
#define DistortedSphereDragForce_H

#include "ParticleForce.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

namespace Foam
{
/*---------------------------------------------------------------------------*\
                       Class DistortedSphereDragForce Declaration
\*---------------------------------------------------------------------------*/

template<class CloudType>
class DistortedSphereDragForce
:
    public ParticleForce<CloudType>
{
    // Private Member Functions

        //- Drag coefficient multiplied by Reynolds number
        scalar CdRe(const scalar Re) const;


public:

    //- Runtime type information
    TypeName("distortedSphereDrag");


    // Constructors

        //- Construct from mesh
        DistortedSphereDragForce
        (
            CloudType& owner,
            const fvMesh& mesh,
            const dictionary& dict
        );

        //- Construct copy
        DistortedSphereDragForce(const DistortedSphereDragForce<CloudType>& df);

        //- Construct and return a clone
        virtual autoPtr<ParticleForce<CloudType> > clone() const
        {
            return autoPtr<ParticleForce<CloudType> >
            (
                new DistortedSphereDragForce<CloudType>(*this)
            );
        }


    //- Destructor
    virtual ~DistortedSphereDragForce();


    // Member Functions

        // Evaluation

            //- Calculate the coupled force
            virtual forceSuSp calcCoupled
            (
                const typename CloudType::parcelType& p,
                const scalar dt,
                const scalar mass,
                const scalar Re,
                const scalar muc
            ) const;
};


// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

} // End namespace Foam

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

#ifdef NoRepository
#   include "DistortedSphereDragForce.C"
#endif

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

#endif

// ************************************************************************* //

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011 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 "DistortedSphereDragForce.H"

// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //

template<class CloudType>
Foam::scalar Foam::DistortedSphereDragForce<CloudType>::CdRe(const scalar Re) const
{
    if (Re > 1000.0)
    {
        return 0.424*Re;
    }
    else
    {
        return 24.0*(1.0 + 1.0/6.0*pow(Re, 2.0/3.0));
    }
}


// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //

template<class CloudType>
Foam::DistortedSphereDragForce<CloudType>::DistortedSphereDragForce
(
    CloudType& owner,
    const fvMesh& mesh,
    const dictionary& dict
)
:
    ParticleForce<CloudType>(owner, mesh, dict, typeName, false)
{}


template<class CloudType>
Foam::DistortedSphereDragForce<CloudType>::DistortedSphereDragForce
(
    const DistortedSphereDragForce<CloudType>& df
)
:
    ParticleForce<CloudType>(df)
{}


// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //

template<class CloudType>
Foam::DistortedSphereDragForce<CloudType>::~DistortedSphereDragForce()
{}


// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //

template<class CloudType>
Foam::forceSuSp Foam::DistortedSphereDragForce<CloudType>::calcCoupled
(
    const typename CloudType::parcelType& p,
    const scalar dt,
    const scalar mass,
    const scalar Re,
    const scalar muc
) const
{
    forceSuSp value(vector::zero, 0.0);

    // limit the drop distortion to y=0 (sphere) and y=1 (disk)
    scalar y = min(max(p.y(),0.0),1.0);

    value.Sp() = mass*0.75*muc*CdRe(Re)*(1+2.632*y)/(p.rho()*sqr(p.d()));

    return value;
}


// ************************************************************************* //

/*---------------------------------------------------------------------------*\
  =========                 |
  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
   \\    /   O peration     |
    \\  /    A nd           | Copyright (C) 2011-2013 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::DistortedSphereDragForce

Description
    Drag model based on assumption of distorted spheres according to:

    \verbatim
     Liu, A.B.; Mather, D.; Reitz, R.D.
     "Effects of Drop Drag and Breakup on Fuel Sprays"
     SAE Paper 930072
     SAE Transactions, Vol. 102, Section 3, Journal of Engines, pp. 63-95, 1993
    \endverbatim

\*---------------------------------------------------------------------------*/

#ifndef DistortedSphereDragForce_H
#define DistortedSphereDragForce_H

#include "ParticleForce.H"

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

namespace Foam
{
/*---------------------------------------------------------------------------*\
                       Class DistortedSphereDragForce Declaration
\*---------------------------------------------------------------------------*/

template<class CloudType>
class DistortedSphereDragForce
:
    public ParticleForce<CloudType>
{
    // Private Member Functions

        //- Drag coefficient multiplied by Reynolds number
        scalar CdRe(const scalar Re) const;


public:

    //- Runtime type information
    TypeName("distortedSphereDrag");


    // Constructors

        //- Construct from mesh
        DistortedSphereDragForce
        (
            CloudType& owner,
            const fvMesh& mesh,
            const dictionary& dict
        );

        //- Construct copy
        DistortedSphereDragForce(const DistortedSphereDragForce<CloudType>& df);

        //- Construct and return a clone
        virtual autoPtr<ParticleForce<CloudType> > clone() const
        {
            return autoPtr<ParticleForce<CloudType> >
            (
                new DistortedSphereDragForce<CloudType>(*this)
            );
        }


    //- Destructor
    virtual ~DistortedSphereDragForce();


    // Member Functions

        // Evaluation

            //- Calculate the coupled force
            virtual forceSuSp calcCoupled
            (
                const typename CloudType::parcelType& p,
                const scalar dt,
                const scalar mass,
                const scalar Re,
                const scalar muc
            ) const;
};


// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

} // End namespace Foam

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

#ifdef NoRepository
#   include "DistortedSphereDragForce.C"
#endif

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

#endif

// ************************************************************************* //

diff --git a/libraries/lagrangian/spray/parcels/derived/basicSprayParcel/makeBasicSprayParcelSubmodels.C b/libraries/lagrangian/spray/parcels/derived/basicSprayParcel/makeBasicSprayParcelSubmodels.C
index 01a480b..893319a 100644
--- a/libraries/lagrangian/spray/parcels/derived/basicSprayParcel/makeBasicSprayParcelSubmodels.C
+++ b/libraries/lagrangian/spray/parcels/derived/basicSprayParcel/makeBasicSprayParcelSubmodels.C
@@ -42,6 +42,7 @@ License
 #include "makeReactingParcelSurfaceFilmModels.H"
 
 // Spray
+#include "DistortedSphereDragForce.H"
 #include "makeSprayParcelAtomizationModels.H"
 #include "makeSprayParcelBreakupModels.H"
 #include "makeSprayParcelCollisionModels.H"
@@ -67,6 +68,7 @@ namespace Foam
     makeReactingParcelSurfaceFilmModels(basicSprayCloud);
 
     // Spray sub-models
+    makeParticleForceModelType(DistortedSphereDragForce, basicSprayCloud);
     makeSprayParcelAtomizationModels(basicSprayCloud);
     makeSprayParcelBreakupModels(basicSprayCloud);
     makeSprayParcelCollisionModels(basicSprayCloud);
diff --git a/libraries/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.C b/libraries/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.C
new file mode 100644
index 0000000..5993e7b
--- /dev/null
+++ b/libraries/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.C
@@ -0,0 +1,98 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2011 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 "DistortedSphereDragForce.H"
+
+// * * * * * * * * * * * * * Private Member Functions  * * * * * * * * * * * //
+
+template<class CloudType>
+Foam::scalar Foam::DistortedSphereDragForce<CloudType>::CdRe(const scalar Re) const
+{
+    if (Re > 1000.0)
+    {
+        return 0.424*Re;
+    }
+    else
+    {
+        return 24.0*(1.0 + 1.0/6.0*pow(Re, 2.0/3.0));
+    }
+}
+
+
+// * * * * * * * * * * * * * * * * Constructors  * * * * * * * * * * * * * * //
+
+template<class CloudType>
+Foam::DistortedSphereDragForce<CloudType>::DistortedSphereDragForce
+(
+    CloudType& owner,
+    const fvMesh& mesh,
+    const dictionary& dict
+)
+:
+    ParticleForce<CloudType>(owner, mesh, dict, typeName, false)
+{}
+
+
+template<class CloudType>
+Foam::DistortedSphereDragForce<CloudType>::DistortedSphereDragForce
+(
+    const DistortedSphereDragForce<CloudType>& df
+)
+:
+    ParticleForce<CloudType>(df)
+{}
+
+
+// * * * * * * * * * * * * * * * * Destructor  * * * * * * * * * * * * * * * //
+
+template<class CloudType>
+Foam::DistortedSphereDragForce<CloudType>::~DistortedSphereDragForce()
+{}
+
+
+// * * * * * * * * * * * * * * * Member Functions  * * * * * * * * * * * * * //
+
+template<class CloudType>
+Foam::forceSuSp Foam::DistortedSphereDragForce<CloudType>::calcCoupled
+(
+    const typename CloudType::parcelType& p,
+    const scalar dt,
+    const scalar mass,
+    const scalar Re,
+    const scalar muc
+) const
+{
+    forceSuSp value(vector::zero, 0.0);
+
+    // limit the drop distortion to y=0 (sphere) and y=1 (disk)
+    scalar y = min(max(p.y(),0.0),1.0);
+
+    value.Sp() = mass*0.75*muc*CdRe(Re)*(1+2.632*y)/(p.rho()*sqr(p.d()));
+
+    return value;
+}
+
+
+// ************************************************************************* //
diff --git a/libraries/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.H b/libraries/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.H
new file mode 100644
index 0000000..bf7cb47
--- /dev/null
+++ b/libraries/lagrangian/spray/submodels/ParticleForces/Drag/DistortedSphereDrag/DistortedSphereDragForce.H
@@ -0,0 +1,126 @@
+/*---------------------------------------------------------------------------*\
+  =========                 |
+  \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox
+   \\    /   O peration     |
+    \\  /    A nd           | Copyright (C) 2011-2013 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::DistortedSphereDragForce
+
+Description
+    Drag model based on assumption of distorted spheres according to:
+
+    \verbatim
+     Liu, A.B.; Mather, D.; Reitz, R.D.
+     "Effects of Drop Drag and Breakup on Fuel Sprays"
+     SAE Paper 930072
+     SAE Transactions, Vol. 102, Section 3, Journal of Engines, pp. 63-95, 1993
+    \endverbatim
+
+\*---------------------------------------------------------------------------*/
+
+#ifndef DistortedSphereDragForce_H
+#define DistortedSphereDragForce_H
+
+#include "ParticleForce.H"
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+namespace Foam
+{
+/*---------------------------------------------------------------------------*\
+                       Class DistortedSphereDragForce Declaration
+\*---------------------------------------------------------------------------*/
+
+template<class CloudType>
+class DistortedSphereDragForce
+:
+    public ParticleForce<CloudType>
+{
+    // Private Member Functions
+
+        //- Drag coefficient multiplied by Reynolds number
+        scalar CdRe(const scalar Re) const;
+
+
+public:
+
+    //- Runtime type information
+    TypeName("distortedSphereDrag");
+
+
+    // Constructors
+
+        //- Construct from mesh
+        DistortedSphereDragForce
+        (
+            CloudType& owner,
+            const fvMesh& mesh,
+            const dictionary& dict
+        );
+
+        //- Construct copy
+        DistortedSphereDragForce(const DistortedSphereDragForce<CloudType>& df);
+
+        //- Construct and return a clone
+        virtual autoPtr<ParticleForce<CloudType> > clone() const
+        {
+            return autoPtr<ParticleForce<CloudType> >
+            (
+                new DistortedSphereDragForce<CloudType>(*this)
+            );
+        }
+
+
+    //- Destructor
+    virtual ~DistortedSphereDragForce();
+
+
+    // Member Functions
+
+        // Evaluation
+
+            //- Calculate the coupled force
+            virtual forceSuSp calcCoupled
+            (
+                const typename CloudType::parcelType& p,
+                const scalar dt,
+                const scalar mass,
+                const scalar Re,
+                const scalar muc
+            ) const;
+};
+
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+} // End namespace Foam
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#ifdef NoRepository
+#   include "DistortedSphereDragForce.C"
+#endif
+
+// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
+
+#endif
+
+// ************************************************************************* //