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             : 
       9             : #include "DataStructures/DataBox/Prefixes.hpp"
      10             : #include "DataStructures/Tensor/TypeAliases.hpp"
      11             : #include "Evolution/Systems/Burgers/BoundaryCorrections/BoundaryCorrection.hpp"
      12             : #include "Evolution/Systems/Burgers/Tags.hpp"
      13             : #include "NumericalAlgorithms/DiscontinuousGalerkin/Formulation.hpp"
      14             : #include "Options/String.hpp"
      15             : #include "Utilities/Serialization/CharmPupable.hpp"
      16             : #include "Utilities/TMPL.hpp"
      17             : 
      18             : /// \cond
      19             : class DataVector;
      20             : namespace gsl {
      21             : template <typename T>
      22             : class not_null;
      23             : }  // namespace gsl
      24             : namespace PUP {
      25             : class er;
      26             : }  // namespace PUP
      27             : /// \endcond
      28             : 
      29             : namespace Burgers::BoundaryCorrections {
      30             : /*!
      31             :  * \brief An HLL (Harten-Lax-van Leer) Riemann solver
      32             :  *
      33             :  * Let \f$U\f$ be the evolved variable, \f$F^i\f$ the flux, and \f$n_i\f$ be
      34             :  * the outward directed unit normal to the interface. Denoting \f$F := n_i
      35             :  * F^i\f$, the HLL boundary correction is \cite Harten1983
      36             :  *
      37             :  * \f{align*}
      38             :  * G_\text{HLL} = \frac{\lambda_\text{max} F_\text{int} +
      39             :  * \lambda_\text{min} F_\text{ext}}{\lambda_\text{max} - \lambda_\text{min}}
      40             :  * - \frac{\lambda_\text{min}\lambda_\text{max}}{\lambda_\text{max} -
      41             :  * \lambda_\text{min}} \left(U_\text{int} - U_\text{ext}\right)
      42             :  * \f}
      43             :  *
      44             :  * where "int" and "ext" stand for interior and exterior, and \cite Davis1988
      45             :  *
      46             :  * \f{align*}
      47             :  * \lambda_\text{min} &= \text{min}\left(U_\text{int},-U_\text{ext}, 0\right) \\
      48             :  * \lambda_\text{max} &= \text{max}\left(U_\text{int},-U_\text{ext}, 0\right),
      49             :  * \f}
      50             :  *
      51             :  * The positive sign in front of the \f$F_{\text{ext}}\f$ in \f$G_\text{HLL}\f$
      52             :  * and the minus signs in front of the \f$U_\text{ext}\f$ terms in
      53             :  * \f$\lambda_\text{min}\f$ and \f$\lambda_\text{max}\f$ terms are necessary
      54             :  * because the outward directed normal of the neighboring element has the
      55             :  * opposite sign, i.e. \f$n_i^{\text{ext}}=-n_i^{\text{int}}\f$. Note that for
      56             :  * either \f$\lambda_\text{min} = 0\f$ or \f$\lambda_\text{max} = 0\f$ (i.e. all
      57             :  * characteristics move in the same direction) the HLL boundary correction
      58             :  * reduces to pure upwinding.
      59             :  *
      60             :  * \note
      61             :  * - In the strong form the `dg_boundary_terms` function returns
      62             :  * \f$G - F_\text{int}\f$
      63             :  * - Some references use \f$S\f$ instead of \f$\lambda\f$ for the
      64             :  * signal/characteristic speeds
      65             :  */
      66           1 : class Hll final : public BoundaryCorrection {
      67             :  private:
      68           0 :   struct CharSpeed : db::SimpleTag {
      69           0 :     using type = Scalar<DataVector>;
      70             :   };
      71             : 
      72             :  public:
      73           0 :   using options = tmpl::list<>;
      74           0 :   static constexpr Options::String help = {
      75             :       "Computes the HLL boundary correction term for the Burgers system."};
      76             : 
      77           0 :   Hll() = default;
      78           0 :   Hll(const Hll&) = default;
      79           0 :   Hll& operator=(const Hll&) = default;
      80           0 :   Hll(Hll&&) = default;
      81           0 :   Hll& operator=(Hll&&) = default;
      82           0 :   ~Hll() override = default;
      83             : 
      84             :   /// \cond
      85             :   explicit Hll(CkMigrateMessage* msg);
      86             :   using PUP::able::register_constructor;
      87             :   WRAPPED_PUPable_decl_template(Hll);  // NOLINT
      88             :   /// \endcond
      89           0 :   void pup(PUP::er& p) override;  // NOLINT
      90             : 
      91           0 :   std::unique_ptr<BoundaryCorrection> get_clone() const override;
      92             : 
      93           0 :   using dg_package_field_tags =
      94             :       tmpl::list<Tags::U, ::Tags::NormalDotFlux<Tags::U>, CharSpeed>;
      95           0 :   using dg_package_data_temporary_tags = tmpl::list<>;
      96           0 :   using dg_package_data_volume_tags = tmpl::list<>;
      97           0 :   using dg_boundary_terms_volume_tags = tmpl::list<>;
      98             : 
      99           0 :   static double dg_package_data(
     100             :       gsl::not_null<Scalar<DataVector>*> packaged_u,
     101             :       gsl::not_null<Scalar<DataVector>*> packaged_normal_dot_flux,
     102             :       gsl::not_null<Scalar<DataVector>*> packaged_char_speed,
     103             :       const Scalar<DataVector>& u,
     104             :       const tnsr::I<DataVector, 1, Frame::Inertial>& flux_u,
     105             :       const tnsr::i<DataVector, 1, Frame::Inertial>& normal_covector,
     106             :       const std::optional<tnsr::I<DataVector, 1, Frame::Inertial>>&
     107             :           mesh_velocity,
     108             :       const std::optional<Scalar<DataVector>>& normal_dot_mesh_velocity);
     109             : 
     110           0 :   static void dg_boundary_terms(
     111             :       gsl::not_null<Scalar<DataVector>*> boundary_correction_u,
     112             :       const Scalar<DataVector>& u_int,
     113             :       const Scalar<DataVector>& normal_dot_flux_u_int,
     114             :       const Scalar<DataVector>& abs_char_speed_int,
     115             :       const Scalar<DataVector>& u_ext,
     116             :       const Scalar<DataVector>& normal_dot_flux_u_ext,
     117             :       const Scalar<DataVector>& abs_char_speed_ext,
     118             :       dg::Formulation dg_formulation);
     119             : };
     120             : }  // namespace Burgers::BoundaryCorrections