two_fluid_navier_stokes.h

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//    |  /           |
//    ' /   __| _` | __|  _ \   __|
//    . \  |   (   | |   (   |\__ `
//   _|\_\_|  \__,_|\__|\___/ ____/
//                   Multi-Physics
//
//  License:         BSD License
//                   Kratos default license: kratos/license.txt
//
//  Main author:     Daniel Diez
//  Co-authors:      Ruben Zorrilla
//
 
#if !defined(KRATOS_TWO_FLUID_NAVIER_STOKES)
#define  KRATOS_TWO_FLUID_NAVIER_STOKES
 
// System includes
 
// Project includes
#include "includes/define.h"
#include "includes/element.h"
#include "includes/variables.h"
#include "includes/serializer.h"
#include "includes/cfd_variables.h"
#include "custom_elements/fluid_element.h"
#include "custom_utilities/fluid_element_utilities.h"
#include "utilities/geometry_utilities.h"
#include "modified_shape_functions/tetrahedra_3d_4_modified_shape_functions.h"
#include "modified_shape_functions/triangle_2d_3_modified_shape_functions.h"
 
namespace Kratos
{
 
/*The "TwoFluidNavierStokes" element is an element based on the Variational Multiscale Stabilization technique (VMS)
* which is designed for the solution of a two fluids (air and a non-air one) problems.
*
* A distinctive feature of the element is the use of 4 LOCAL enrichment functions, which allows to model
* a discontinuity in both the pressure field and in its gradient.
* The enrichment functions are obtained by duplicating all of the degrees of freedom of the element.
* Since the enrichment is performed elementwise, a purely local static condensation step is performed,
* meaning that no extra degrees of freedom are added..
*
* Since a jump in the pressure can be considered, the element shall be able to habdle moderate changes of the viscosity
* between the two fluids to be considered*/
 
 
 
 
 
 
template< class TElementData >
class TwoFluidNavierStokes : public FluidElement<TElementData>
{
public:
 
    KRATOS_CLASS_INTRUSIVE_POINTER_DEFINITION(TwoFluidNavierStokes);
 
 
    typedef Node NodeType;
    typedef Geometry<NodeType> GeometryType;
    typedef Geometry<NodeType>::PointsArrayType NodesArrayType;
    typedef Vector VectorType;
    typedef Matrix MatrixType;
    typedef std::size_t IndexType;
    typedef std::size_t SizeType;
    typedef std::vector<std::size_t> EquationIdVectorType;
    typedef std::vector< Dof<double>::Pointer > DofsVectorType;
    typedef PointerVectorSet<Dof<double>, IndexedObject> DofsArrayType;
    typedef typename FluidElement<TElementData>::ShapeFunctionsType ShapeFunctionsType;
    typedef typename FluidElement<TElementData>::ShapeFunctionDerivativesType ShapeFunctionDerivativesType;
    typedef typename FluidElement<TElementData>::ShapeFunctionDerivativesArrayType ShapeFunctionDerivativesArrayType;
    constexpr static unsigned int Dim = FluidElement<TElementData>::Dim;
    constexpr static unsigned int NumNodes = FluidElement<TElementData>::NumNodes;
    constexpr static unsigned int BlockSize = FluidElement<TElementData>::BlockSize;
    constexpr static unsigned int LocalSize = FluidElement<TElementData>::LocalSize;
    constexpr static unsigned int StrainSize = (Dim - 1) * 3;
 
 
 
    TwoFluidNavierStokes(IndexType NewId = 0);
 
 
    TwoFluidNavierStokes(IndexType NewId, const NodesArrayType& ThisNodes);
 
 
    TwoFluidNavierStokes(IndexType NewId, GeometryType::Pointer pGeometry);
 
 
    TwoFluidNavierStokes(IndexType NewId, GeometryType::Pointer pGeometry, Properties::Pointer pProperties);
 
    virtual ~TwoFluidNavierStokes();
 
 
 
 
    Element::Pointer Create(IndexType NewId,
        NodesArrayType const& ThisNodes,
        Properties::Pointer pProperties) const override;
 
 
    Element::Pointer Create(IndexType NewId,
        GeometryType::Pointer pGeom,
        Properties::Pointer pProperties) const override;
 
 
    void CalculateLocalSystem(
        MatrixType &rLeftHandSideMatrix,
        VectorType &rRightHandSideVector,
        const ProcessInfo &rCurrentProcessInfo) override;
 
 
    void CalculateRightHandSide(
        VectorType &rRightHandSideVector,
        const ProcessInfo &rCurrentProcessInfo) override;
 
 
    int Check(const ProcessInfo &rCurrentProcessInfo) const override;
 
 
 
    const Parameters GetSpecifications() const override;
 
    std::string Info() const override;
 
    void PrintInfo(std::ostream& rOStream) const override;
 
 
 
 
 
    void CalculateOnIntegrationPoints(
        const Variable<double> &rVariable,
        std::vector<double> &rValues,
        const ProcessInfo &rCurrentProcessInfo ) override;
 
 
protected:
 
 
 
 
    void AddTimeIntegratedSystem(
        TElementData& rData,
        MatrixType& rLHS,
        VectorType& rRHS) override;
 
    void AddTimeIntegratedLHS(
        TElementData& rData,
        MatrixType& rLHS) override;
 
    void AddTimeIntegratedRHS(
        TElementData& rData,
        VectorType& rRHS) override;
 
    virtual void ComputeGaussPointLHSContribution(
        TElementData& rData,
        MatrixType& rLHS);
 
    virtual void ComputeGaussPointRHSContribution(
        TElementData& rData,
        VectorType& rRHS);
 
    virtual void ComputeGaussPointEnrichmentContributions(
        TElementData& rData,
        MatrixType& rV,
        MatrixType& rH,
        MatrixType& rKee,
        VectorType& rRHS_ee);
 
 
    void UpdateIntegrationPointData(
        TElementData& rData,
        unsigned int IntegrationPointIndex,
        double Weight,
        const typename TElementData::MatrixRowType& rN,
        const typename TElementData::ShapeDerivativesType& rDN_DX) const override;
 
 
    void UpdateIntegrationPointData(
        TElementData& rData,
        unsigned int IntegrationPointIndex,
        double Weight,
        const typename TElementData::MatrixRowType& rN,
        const typename TElementData::ShapeDerivativesType& rDN_DX,
        const typename TElementData::MatrixRowType& rNenr,
        const typename TElementData::ShapeDerivativesType& rDN_DXenr) const;
 
    virtual void PressureGradientStabilization(
        const TElementData& rData,
        const Vector& rInterfaceWeights,
        const Matrix& rEnrInterfaceShapeFunctionPos,
        const Matrix& rEnrInterfaceShapeFunctionNeg,
        const GeometryType::ShapeFunctionsGradientsType& rInterfaceShapeDerivatives,
        MatrixType& rKeeTot,
        VectorType& rRHSeeTot);
 
    void CalculateStrainRate(TElementData& rData) const override;
 
 
 
 
 
 
 
    friend class Serializer;
 
    void save(Serializer& rSerializer) const override;
 
    void load(Serializer& rSerializer) override;
 
private:
 
    void ComputeSplitting(
        TElementData& rData,
        MatrixType& rShapeFunctionsPos,
        MatrixType& rShapeFunctionsNeg,
        MatrixType& rEnrichedShapeFunctionsPos,
        MatrixType& rEnrichedShapeFunctionsNeg,
        GeometryType::ShapeFunctionsGradientsType& rShapeDerivativesPos,
        GeometryType::ShapeFunctionsGradientsType& rShapeDerivativesNeg,
        GeometryType::ShapeFunctionsGradientsType& rEnrichedShapeDerivativesPos,
        GeometryType::ShapeFunctionsGradientsType& rEnrichedShapeDerivativesNeg,
        ModifiedShapeFunctions::Pointer pModifiedShapeFunctions);
 
    void ComputeSplitInterface(
        const TElementData& rData,
        MatrixType& rInterfaceShapeFunctionNeg,
        MatrixType& rEnrInterfaceShapeFunctionPos,
        MatrixType& rEnrInterfaceShapeFunctionNeg,
        GeometryType::ShapeFunctionsGradientsType& rInterfaceShapeDerivativesNeg,
        Vector& rInterfaceWeightsNeg,
        std::vector<array_1d<double,3>>& rInterfaceNormalsNeg,
        ModifiedShapeFunctions::Pointer pModifiedShapeFunctions);
 
    ModifiedShapeFunctions::UniquePointer pGetModifiedShapeFunctionsUtility(
        const GeometryType::Pointer pGeometry,
        const Vector& rDistances);
 
    void CalculateCurvatureOnInterfaceGaussPoints(
        const Matrix& rInterfaceShapeFunctions,
        Vector& rInterfaceCurvature);
 
    void SurfaceTension(
        const double SurfaceTensionCoefficient,
        const Vector& rCurvature,
        const Vector& rInterfaceWeights,
        const Matrix& rInterfaceShapeFunctions,
        const std::vector<array_1d<double,3>>& rInterfaceNormalsNeg,
        VectorType& rRHS);
 
 
    void CondenseEnrichmentWithContinuity(
        const TElementData& rData,
        Matrix& rLeftHandSideMatrix,
        VectorType& rRightHandSideVector,
        const MatrixType& rVTot,
        const MatrixType& rHTot,
        MatrixType& rKeeTot,
        const VectorType& rRHSeeTot);
 
    void CondenseEnrichment(
        Matrix& rLeftHandSideMatrix,
        VectorType& rRightHandSideVector,
        const MatrixType& rVTot,
        const MatrixType& rHTot,
        MatrixType& rKeeTot,
        const VectorType& rRHSeeTot);
 
    void AddSurfaceTensionContribution(
        const TElementData& rData,
        MatrixType& rInterfaceShapeFunction,
        MatrixType& rEnrInterfaceShapeFunctionPos,
        MatrixType& rEnrInterfaceShapeFunctionNeg,
        GeometryType::ShapeFunctionsGradientsType& rInterfaceShapeDerivatives,
        Vector& rInterfaceWeights,
        std::vector<array_1d<double, 3>>& rInterfaceNormalsNeg,
        Matrix &rLeftHandSideMatrix,
        VectorType &rRightHandSideVector,
        const MatrixType &rHtot,
        const MatrixType &rVtot,
        MatrixType &rKeeTot,
        VectorType &rRHSeeTot);
 
 
 
 
    TwoFluidNavierStokes& operator=(TwoFluidNavierStokes const& rOther);
 
    TwoFluidNavierStokes(TwoFluidNavierStokes const& rOther);
 
 
}; // Class TwoFluidNavierStokes
 
 
template< class TElementData >
inline std::istream& operator >> (std::istream& rIStream,
    TwoFluidNavierStokes<TElementData>& rThis)
{
    return rIStream;
}
 
template< class TElementData >
inline std::ostream& operator <<(std::ostream& rOStream,
    const TwoFluidNavierStokes<TElementData>& rThis)
{
    rThis.PrintInfo(rOStream);
    rOStream << std::endl;
    rThis.PrintData(rOStream);
 
    return rOStream;
}
 
} // namespace Kratos.
 
#endif // KRATOS_TWO_FLUID_NAVIER_STOKES