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/Systems/ScalarAdvection/BoundaryCorrections/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 BoundaryCorrection<Dim> {
      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<Dim>> 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