Line data    Source code

       1             : // The libMesh Finite Element Library.
       2             : // Copyright (C) 2002-2025 Benjamin S. Kirk, John W. Peterson, Roy H. Stogner
       3             : 
       4             : // This library is free software; you can redistribute it and/or
       5             : // modify it under the terms of the GNU Lesser General Public
       6             : // License as published by the Free Software Foundation; either
       7             : // version 2.1 of the License, or (at your option) any later version.
       8             : 
       9             : // This library is distributed in the hope that it will be useful,
      10             : // but WITHOUT ANY WARRANTY; without even the implied warranty of
      11             : // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      12             : // Lesser General Public License for more details.
      13             : 
      14             : // You should have received a copy of the GNU Lesser General Public
      15             : // License along with this library; if not, write to the Free Software
      16             : // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
      17             : 
      18             : 
      19             : 
      20             : #ifndef LIBMESH_DG_FEM_CONTEXT_H
      21             : #define LIBMESH_DG_FEM_CONTEXT_H
      22             : 
      23             : // Local Includes
      24             : #include "libmesh/fem_context.h"
      25             : 
      26             : 
      27             : namespace libMesh
      28             : {
      29             : 
      30             : /**
      31             :  * This class extends FEMContext in order to provide extra data
      32             :  * required to perform local element residual and Jacobian assembly
      33             :  * in the case of a discontinuous Galerkin (DG) discretization.
      34             :  *
      35             :  * \author David Knezevic
      36             :  * \date 2015
      37             :  * \brief Extends FEMContext to work for DG problems.
      38             :  */
      39         580 : class DGFEMContext : public FEMContext
      40             : {
      41             : public:
      42             : 
      43             :   /**
      44             :    * Constructor.  Allocates some but fills no data structures.
      45             :    */
      46             :   explicit
      47             :   DGFEMContext (const System & sys);
      48             : 
      49             :   /**
      50             :    * Destructor.
      51             :    */
      52             :   virtual ~DGFEMContext ();
      53             : 
      54             :   /**
      55             :    * Override side_fe_reinit to set a boolean flag so that by
      56             :    * default DG terms are assumed to be inactive. DG terms are
      57             :    * only active if neighbor_side_fe_reinit is called.
      58             :    */
      59             :   virtual void side_fe_reinit () override;
      60             : 
      61             :   /**
      62             :    * Initialize neighbor side data needed to assemble DG terms.
      63             :    * The neighbor element is determined by the current value of
      64             :    * get_neighbor().
      65             :    */
      66             :   void neighbor_side_fe_reinit ();
      67             : 
      68             :   /**
      69             :    * Accessor for neighbor dof indices
      70             :    */
      71           0 :   const std::vector<dof_id_type> & get_neighbor_dof_indices() const
      72           0 :   { return _neighbor_dof_indices; }
      73             : 
      74             :   /**
      75             :    * Accessor for element dof indices of a particular variable corresponding
      76             :    * to the index argument.
      77             :    */
      78             :   const std::vector<dof_id_type> & get_neighbor_dof_indices( unsigned int var ) const
      79             :   { return _neighbor_dof_indices_var[var]; }
      80             : 
      81             :   /**
      82             :    * Const accessor for neighbor residual.
      83             :    */
      84             :   const DenseVector<Number> & get_neighbor_residual() const
      85             :   { return _neighbor_residual; }
      86             : 
      87             :   /**
      88             :    * Non-const accessor for neighbor residual.
      89             :    */
      90             :   DenseVector<Number> & get_neighbor_residual()
      91             :   { return _neighbor_residual; }
      92             : 
      93             :   /**
      94             :    * Const accessor for neighbor residual of a particular variable corresponding
      95             :    * to the variable index argument.
      96             :    */
      97             :   const DenseSubVector<Number> & get_neighbor_residual( unsigned int var ) const
      98             :   { return *(_neighbor_subresiduals[var]); }
      99             : 
     100             :   /**
     101             :    * Non-const accessor for neighbor residual of a particular variable corresponding
     102             :    * to the variable index argument.
     103             :    */
     104             :   DenseSubVector<Number> & get_neighbor_residual( unsigned int var )
     105             :   { return *(_neighbor_subresiduals[var]); }
     106             : 
     107             :   /**
     108             :    * Const accessor for element-element Jacobian.
     109             :    */
     110             :   const DenseMatrix<Number> & get_elem_elem_jacobian() const
     111             :   { return _elem_elem_jacobian; }
     112             : 
     113             :   /**
     114             :    * Non-const accessor for element-element Jacobian.
     115             :    */
     116           0 :   DenseMatrix<Number> & get_elem_elem_jacobian()
     117           0 :   { return _elem_elem_jacobian; }
     118             : 
     119             :   /**
     120             :    * Const accessor for element-element Jacobian of particular variables corresponding
     121             :    * to the variable index arguments.
     122             :    */
     123             :   const DenseSubMatrix<Number> & get_elem_elem_jacobian( unsigned int var1, unsigned int var2 ) const
     124             :   { return *(_elem_elem_subjacobians[var1][var2]); }
     125             : 
     126             :   /**
     127             :    * Non-const accessor for element-element Jacobian of particular variables corresponding
     128             :    * to the variable index arguments.
     129             :    */
     130             :   DenseSubMatrix<Number> & get_elem_elem_jacobian( unsigned int var1, unsigned int var2 )
     131             :   { return *(_elem_elem_subjacobians[var1][var2]); }
     132             : 
     133             :   /**
     134             :    * Const accessor for element-neighbor Jacobian.
     135             :    */
     136             :   const DenseMatrix<Number> & get_elem_neighbor_jacobian() const
     137             :   { return _elem_neighbor_jacobian; }
     138             : 
     139             :   /**
     140             :    * Non-const accessor for element -neighborJacobian.
     141             :    */
     142           0 :   DenseMatrix<Number> & get_elem_neighbor_jacobian()
     143           0 :   { return _elem_neighbor_jacobian; }
     144             : 
     145             :   /**
     146             :    * Const accessor for element-neighbor Jacobian of particular variables corresponding
     147             :    * to the variable index arguments.
     148             :    */
     149             :   const DenseSubMatrix<Number> & get_elem_neighbor_jacobian( unsigned int var1, unsigned int var2 ) const
     150             :   { return *(_elem_neighbor_subjacobians[var1][var2]); }
     151             : 
     152             :   /**
     153             :    * Non-const accessor for element-neighbor Jacobian of particular variables corresponding
     154             :    * to the variable index arguments.
     155             :    */
     156             :   DenseSubMatrix<Number> & get_elem_neighbor_jacobian( unsigned int var1, unsigned int var2 )
     157             :   { return *(_elem_neighbor_subjacobians[var1][var2]); }
     158             : 
     159             :   /**
     160             :    * Const accessor for element-neighbor Jacobian.
     161             :    */
     162             :   const DenseMatrix<Number> & get_neighbor_elem_jacobian() const
     163             :   { return _neighbor_elem_jacobian; }
     164             : 
     165             :   /**
     166             :    * Non-const accessor for element Jacobian.
     167             :    */
     168           0 :   DenseMatrix<Number> & get_neighbor_elem_jacobian()
     169           0 :   { return _neighbor_elem_jacobian; }
     170             : 
     171             :   /**
     172             :    * Const accessor for neighbor-element Jacobian of particular variables corresponding
     173             :    * to the variable index arguments.
     174             :    */
     175             :   const DenseSubMatrix<Number> & get_neighbor_elem_jacobian( unsigned int var1, unsigned int var2 ) const
     176             :   { return *(_neighbor_elem_subjacobians[var1][var2]); }
     177             : 
     178             :   /**
     179             :    * Non-const accessor for neighbor-element Jacobian of particular variables corresponding
     180             :    * to the variable index arguments.
     181             :    */
     182             :   DenseSubMatrix<Number> & get_neighbor_elem_jacobian( unsigned int var1, unsigned int var2 )
     183             :   { return *(_neighbor_elem_subjacobians[var1][var2]); }
     184             : 
     185             :   /**
     186             :    * Const accessor for element-neighbor Jacobian.
     187             :    */
     188             :   const DenseMatrix<Number> & get_neighbor_neighbor_jacobian() const
     189             :   { return _neighbor_neighbor_jacobian; }
     190             : 
     191             :   /**
     192             :    * Non-const accessor for element Jacobian.
     193             :    */
     194           0 :   DenseMatrix<Number> & get_neighbor_neighbor_jacobian()
     195           0 :   { return _neighbor_neighbor_jacobian; }
     196             : 
     197             :   /**
     198             :    * Const accessor for neighbor-neighbor Jacobian of particular variables corresponding
     199             :    * to the variable index arguments.
     200             :    */
     201             :   const DenseSubMatrix<Number> & get_neighbor_neighbor_jacobian( unsigned int var1, unsigned int var2 ) const
     202             :   { return *(_neighbor_neighbor_subjacobians[var1][var2]); }
     203             : 
     204             :   /**
     205             :    * Non-const accessor for neighbor-neighbor Jacobian of particular variables corresponding
     206             :    * to the variable index arguments.
     207             :    */
     208             :   DenseSubMatrix<Number> & get_neighbor_neighbor_jacobian( unsigned int var1, unsigned int var2 )
     209             :   { return *(_neighbor_neighbor_subjacobians[var1][var2]); }
     210             : 
     211             :   /**
     212             :    * Set the neighbor element which we will use to assemble DG terms.
     213             :    *
     214             :    * \note We do not assume that this element is get_elem().neighbor(side)
     215             :    * because we also need to be able to handle the special case of DG terms on
     216             :    * "cracks" in a mesh to model certain types of interface conditions. In this
     217             :    * case, we need to be able to specify the neighbor element manually.
     218             :    * Also, this should give us more flexibility to handle non-conforming meshes.
     219             :    */
     220             :   void set_neighbor(const Elem & neighbor)
     221             :   { _neighbor = &neighbor; }
     222             : 
     223             :   /**
     224             :    * Accessor for current neighbor Elem object for assembling DG terms.
     225             :    */
     226        4800 :   const Elem & get_neighbor() const
     227       40800 :   { return *_neighbor; }
     228             : 
     229             :   /**
     230             :    * Are the DG terms active, i.e. have they been assembled?
     231             :    */
     232        9780 :   bool dg_terms_are_active() const
     233      111880 :   { return _dg_terms_active; }
     234             : 
     235             :   /**
     236             :    * Accessor for neighbor edge/face (2D/3D) finite element object for variable var.
     237             :    */
     238             :   template<typename OutputShape>
     239             :   void get_neighbor_side_fe( unsigned int var, FEGenericBase<OutputShape> *& fe ) const;
     240             : 
     241             : private:
     242             : 
     243             :   /**
     244             :    * Current neighbor element for assembling DG terms.
     245             :    */
     246             :   const Elem * _neighbor;
     247             : 
     248             :   /**
     249             :    * Residual vector of the neighbor component.
     250             :    */
     251             :   DenseVector<Number> _neighbor_residual;
     252             : 
     253             :   /**
     254             :    * The DG Jacobian terms.
     255             :    * Trial and test functions come from either element or neighbor.
     256             :    */
     257             :   DenseMatrix<Number> _elem_elem_jacobian;
     258             :   DenseMatrix<Number> _elem_neighbor_jacobian;
     259             :   DenseMatrix<Number> _neighbor_elem_jacobian;
     260             :   DenseMatrix<Number> _neighbor_neighbor_jacobian;
     261             : 
     262             :   /**
     263             :    * Element residual subvectors and Jacobian submatrices
     264             :    */
     265             :   std::vector<std::unique_ptr<DenseSubVector<Number>>> _neighbor_subresiduals;
     266             :   std::vector<std::vector<std::unique_ptr<DenseSubMatrix<Number>>>> _elem_elem_subjacobians;
     267             :   std::vector<std::vector<std::unique_ptr<DenseSubMatrix<Number>>>> _elem_neighbor_subjacobians;
     268             :   std::vector<std::vector<std::unique_ptr<DenseSubMatrix<Number>>>> _neighbor_elem_subjacobians;
     269             :   std::vector<std::vector<std::unique_ptr<DenseSubMatrix<Number>>>> _neighbor_neighbor_subjacobians;
     270             : 
     271             :   /**
     272             :    * Global Degree of freedom index lists for the neighbor element
     273             :    */
     274             :   std::vector<dof_id_type> _neighbor_dof_indices;
     275             :   std::vector<std::vector<dof_id_type>> _neighbor_dof_indices_var;
     276             : 
     277             :   /**
     278             :    * Finite element objects for each variable's
     279             :    * sides on the neighbor element.
     280             :    * We do not need FE objects for neighbor element
     281             :    * interior since we just need to handle DG interface
     282             :    * terms here.
     283             :    */
     284             :   std::map<FEType, std::unique_ptr<FEAbstract>> _neighbor_side_fe;
     285             : 
     286             :   /**
     287             :    * Pointers to the same finite element objects on the neighbor element,
     288             :    * but indexed by variable number
     289             :    */
     290             :   std::vector<FEAbstract *> _neighbor_side_fe_var;
     291             : 
     292             :   /**
     293             :    * Boolean flag to indicate whether or not the DG terms have been
     294             :    * assembled and should be used in the global matrix assembly.
     295             :    */
     296             :   bool _dg_terms_active;
     297             : };
     298             : 
     299             : template<typename OutputShape>
     300             : inline
     301             : void DGFEMContext::get_neighbor_side_fe( unsigned int var, FEGenericBase<OutputShape> *& fe ) const
     302             : {
     303             :   libmesh_assert_less ( var, _neighbor_side_fe_var.size() );
     304             :   fe = cast_ptr<FEGenericBase<OutputShape> *>( _neighbor_side_fe_var[var] );
     305             : }
     306             : 
     307             : } // namespace libMesh
     308             : 
     309             : #endif // LIBMESH_FEM_CONTEXT_H