Line data    Source code

       1            0 : // Distributed under the MIT License.
       2              : // See LICENSE.txt for details.
       3              : 
       4              : #pragma once
       5              : 
       6              : #include <memory>
       7              : #include <optional>
       8              : #include <pup.h>
       9              : 
      10              : #include "DataStructures/DataBox/Prefixes.hpp"
      11              : #include "DataStructures/DataVector.hpp"
      12              : #include "DataStructures/Tensor/TypeAliases.hpp"
      13              : #include "Evolution/BoundaryCorrection.hpp"
      14              : #include "Evolution/Systems/ScalarAdvection/Tags.hpp"
      15              : #include "NumericalAlgorithms/DiscontinuousGalerkin/Formulation.hpp"
      16              : #include "Options/String.hpp"
      17              : #include "Utilities/Gsl.hpp"
      18              : #include "Utilities/Serialization/CharmPupable.hpp"
      19              : #include "Utilities/TMPL.hpp"
      20              : 
      21              : namespace ScalarAdvection {
      22              : namespace BoundaryCorrections {
      23              : /*!
      24              :  * \brief A Rusanov/local Lax-Friedrichs Riemann solver
      25              :  *
      26              :  * Let \f$U\f$ be the evolved scalar variable, \f$F^i\f$ the corresponding
      27              :  * fluxes, and \f$n_i\f$ be the outward directed unit normal to the interface.
      28              :  * Denoting \f$F := n_i F^i\f$, the %Rusanov boundary correction is
      29              :  *
      30              :  * \f{align*}
      31              :  * G_\text{Rusanov} = \frac{F_\text{int} - F_\text{ext}}{2} -
      32              :  * \frac{\text{max}\left(|\lambda_\text{int}|,
      33              :  * |\lambda_\text{ext}|\right)}{2} \left(U_\text{ext} - U_\text{int}\right),
      34              :  * \f}
      35              :  *
      36              :  * where "int" and "ext" stand for interior and exterior, and
      37              :  * \f$\lambda\f$ is the characteristic/signal speed. The minus sign in
      38              :  * front of the \f$F_{\text{ext}}\f$ is necessary because the outward directed
      39              :  * normal of the neighboring element has the opposite sign, i.e.
      40              :  * \f$n_i^{\text{ext}}=-n_i^{\text{int}}\f$.
      41              :  *
      42              :  * For the ScalarAdvection system, \f$\lambda\f$ is given as
      43              :  *
      44              :  * \f{align*}
      45              :  * \lambda = |v| = \sqrt{v^iv_i}
      46              :  * \f}
      47              :  *
      48              :  * where \f$v^i\f$ is the advection velocity field.
      49              :  *
      50              :  * \note In the strong form the `dg_boundary_terms` function returns
      51              :  * \f$G - F_\text{int}\f$
      52              :  */
      53              : template <size_t Dim>
      54            1 : class Rusanov final : public evolution::BoundaryCorrection {
      55              :  private:
      56            0 :   struct AbsCharSpeed : db::SimpleTag {
      57            0 :     using type = Scalar<DataVector>;
      58              :   };
      59              : 
      60              :  public:
      61            0 :   using options = tmpl::list<>;
      62            0 :   static constexpr Options::String help = {
      63              :       "Computes the Rusanov or local Lax-Friedrichs boundary correction term "
      64              :       "for the ScalarAdvection system."};
      65              : 
      66            0 :   Rusanov() = default;
      67            0 :   Rusanov(const Rusanov&) = default;
      68            0 :   Rusanov& operator=(const Rusanov&) = default;
      69            0 :   Rusanov(Rusanov&&) = default;
      70            0 :   Rusanov& operator=(Rusanov&&) = default;
      71            0 :   ~Rusanov() override = default;
      72              : 
      73              :   /// \cond
      74              :   explicit Rusanov(CkMigrateMessage* msg);
      75              :   using PUP::able::register_constructor;
      76              :   WRAPPED_PUPable_decl_template(Rusanov);  // NOLINT
      77              :   /// \endcond
      78            0 :   void pup(PUP::er& p) override;  // NOLINT
      79              : 
      80            0 :   std::unique_ptr<BoundaryCorrection> get_clone() const override;
      81              : 
      82            0 :   using dg_package_field_tags =
      83              :       tmpl::list<Tags::U, ::Tags::NormalDotFlux<Tags::U>, AbsCharSpeed>;
      84            0 :   using dg_package_data_temporary_tags = tmpl::list<Tags::VelocityField<Dim>>;
      85            0 :   using dg_package_data_volume_tags = tmpl::list<>;
      86            0 :   using dg_boundary_terms_volume_tags = tmpl::list<>;
      87              : 
      88            0 :   static double dg_package_data(
      89              :       gsl::not_null<Scalar<DataVector>*> packaged_u,
      90              :       gsl::not_null<Scalar<DataVector>*> packaged_normal_dot_flux_u,
      91              :       gsl::not_null<Scalar<DataVector>*> packaged_abs_char_speed,
      92              :       const Scalar<DataVector>& u,
      93              :       const tnsr::I<DataVector, Dim, Frame::Inertial>& flux_u,
      94              :       const tnsr::I<DataVector, Dim, Frame::Inertial>& velocity_field,
      95              :       const tnsr::i<DataVector, Dim, Frame::Inertial>& normal_covector,
      96              :       const std::optional<tnsr::I<DataVector, Dim, Frame::Inertial>>&
      97              :           mesh_velocity,
      98              :       const std::optional<Scalar<DataVector>>& normal_dot_mesh_velocity);
      99              : 
     100            0 :   static void dg_boundary_terms(
     101              :       gsl::not_null<Scalar<DataVector>*> boundary_correction_u,
     102              :       const Scalar<DataVector>& u_int,
     103              :       const Scalar<DataVector>& normal_dot_flux_u_int,
     104              :       const Scalar<DataVector>& abs_char_speed_int,
     105              :       const Scalar<DataVector>& u_ext,
     106              :       const Scalar<DataVector>& normal_dot_flux_u_ext,
     107              :       const Scalar<DataVector>& abs_char_speed_ext,
     108              :       dg::Formulation dg_formulation);
     109              : };
     110              : }  // namespace BoundaryCorrections
     111              : }  // namespace ScalarAdvection