Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include <array>
       7             : #include <boost/functional/hash.hpp>  // IWYU pragma: keep
       8             : #include <cstddef>
       9             : #include <optional>
      10             : #include <string>
      11             : #include <unordered_map>
      12             : #include <utility>
      13             : 
      14             : #include "DataStructures/Tensor/TypeAliases.hpp"
      15             : #include "Domain/SizeOfElement.hpp"
      16             : #include "Domain/Tags.hpp"  // IWYU pragma: keep
      17             : #include "Evolution/DiscontinuousGalerkin/Limiters/Tags.hpp"
      18             : #include "Evolution/DiscontinuousGalerkin/Limiters/Weno.hpp"
      19             : #include "Evolution/DiscontinuousGalerkin/Limiters/WenoType.hpp"
      20             : #include "Evolution/DiscontinuousGalerkin/NormalVectorTags.hpp"
      21             : #include "Evolution/Systems/NewtonianEuler/Limiters/VariablesToLimit.hpp"
      22             : #include "Evolution/Systems/NewtonianEuler/Tags.hpp"
      23             : #include "Options/Auto.hpp"
      24             : #include "Options/String.hpp"
      25             : #include "PointwiseFunctions/Hydro/TagsDeclarations.hpp"
      26             : #include "Utilities/TMPL.hpp"
      27             : 
      28             : /// \cond
      29             : class DataVector;
      30             : template <size_t VolumeDim>
      31             : class Direction;
      32             : template <size_t VolumeDim>
      33             : class Element;
      34             : template <size_t VolumeDim>
      35             : class ElementId;
      36             : template <size_t VolumeDim>
      37             : class Mesh;
      38             : template <size_t VolumeDim>
      39             : class OrientationMap;
      40             : 
      41             : namespace EquationsOfState {
      42             : template <bool IsRelativistic, size_t ThermodynamicDim>
      43             : class EquationOfState;
      44             : }  // namespace EquationsOfState
      45             : 
      46             : namespace gsl {
      47             : template <typename T>
      48             : class not_null;
      49             : }  // namespace gsl
      50             : 
      51             : namespace PUP {
      52             : class er;
      53             : }  // namespace PUP
      54             : /// \endcond
      55             : 
      56             : namespace NewtonianEuler {
      57             : namespace Limiters {
      58             : 
      59             : /// \ingroup LimitersGroup
      60             : /// \brief A compact-stencil WENO limiter for the NewtonianEuler system.
      61             : ///
      62             : /// Implements the simple WENO limiter of \cite Zhong2013 and the Hermite WENO
      63             : /// (HWENO) limiter of \cite Zhu2016. See the documentation of the
      64             : /// system-agnostic ::Limiters::Weno limiter for a general discussion of the
      65             : /// algorithm and the various options that control the action of the limiter.
      66             : //
      67             : /// This implemention is specialized to the NewtonianEuler evolution system.
      68             : /// By specializing the limiter to the system, we can add a few features that
      69             : /// improve its robustness:
      70             : /// - the troubled-cell indicator (TCI) can be specialized to the features of
      71             : ///   the evolution system.
      72             : /// - the limiter can be applied to the system's characteristic variables. This
      73             : ///   is the recommendation of the reference, because it reduces spurious
      74             : ///   oscillations in the post-limiter solution.
      75             : /// - after limiting, the solution can be processed to remove any remaining
      76             : ///   unphysical values like negative densities and pressures. We do this by
      77             : ///   scaling the solution around its mean (a "flattener" or "bounds-preserving"
      78             : ///   filter). Note: the flattener is applied to all elements, including those
      79             : ///   where the limiter did not act to reduce the solution's slopes.
      80             : ///
      81             : /// The matrix of TCI, variables to limit, post-processing, etc. choices can
      82             : /// rapidly grow large. Here we reduce the possibilities by tying the TCI to the
      83             : /// limiter in keeping with each limiter's main reference: HWENO uses the KXRCF
      84             : /// TCI and simple WENO uses the TVB TCI. To fully explore the matrix of
      85             : /// possibilities, the source code could be generalized --- however, experience
      86             : /// suggests it is unlikely that there exists one combination that will perform
      87             : /// remarkably better than the others.
      88             : template <size_t VolumeDim>
      89           1 : class Weno {
      90             :  public:
      91           0 :   using ConservativeVarsWeno = ::Limiters::Weno<
      92             :       VolumeDim, tmpl::list<NewtonianEuler::Tags::MassDensityCons,
      93             :                             NewtonianEuler::Tags::MomentumDensity<VolumeDim>,
      94             :                             NewtonianEuler::Tags::EnergyDensity>>;
      95             : 
      96           0 :   struct VariablesToLimit {
      97           0 :     using type = NewtonianEuler::Limiters::VariablesToLimit;
      98           0 :     static type suggested_value() {
      99             :       return NewtonianEuler::Limiters::VariablesToLimit::Characteristic;
     100             :     }
     101           0 :     static constexpr Options::String help = {
     102             :         "Variable representation on which to apply the limiter"};
     103             :   };
     104             :   // Future design improvement: attach the TvbConstant/KxrcfConstant to the
     105             :   // limiter type, so that it isn't necessary to specify both (but with one
     106             :   // required to be 'None') in each input file.
     107           0 :   struct TvbConstant {
     108           0 :     using type = Options::Auto<double, Options::AutoLabel::None>;
     109           0 :     static constexpr Options::String help = {
     110             :         "Constant in RHS of the TVB minmod TCI, used when Type = SimpleWeno"};
     111             :   };
     112           0 :   struct KxrcfConstant {
     113           0 :     using type = Options::Auto<double, Options::AutoLabel::None>;
     114           0 :     static constexpr Options::String help = {
     115             :         "Constant in RHS of KXRCF TCI, used when Type = Hweno"};
     116             :   };
     117           0 :   struct ApplyFlattener {
     118           0 :     using type = bool;
     119           0 :     static constexpr Options::String help = {
     120             :         "Flatten after limiting to restore pointwise positivity"};
     121             :   };
     122           0 :   using options =
     123             :       tmpl::list<typename ConservativeVarsWeno::Type, VariablesToLimit,
     124             :                  typename ConservativeVarsWeno::NeighborWeight, TvbConstant,
     125             :                  KxrcfConstant, ApplyFlattener,
     126             :                  typename ConservativeVarsWeno::DisableForDebugging>;
     127           0 :   static constexpr Options::String help = {
     128             :       "A WENO limiter specialized to the NewtonianEuler system"};
     129           0 :   static std::string name() { return "NewtonianEulerWeno"; };
     130             : 
     131           0 :   Weno(::Limiters::WenoType weno_type,
     132             :        NewtonianEuler::Limiters::VariablesToLimit vars_to_limit,
     133             :        double neighbor_linear_weight, std::optional<double> tvb_constant,
     134             :        std::optional<double> kxrcf_constant, bool apply_flattener,
     135             :        bool disable_for_debugging = false,
     136             :        const Options::Context& context = {});
     137             : 
     138           0 :   Weno() = default;
     139           0 :   Weno(const Weno& /*rhs*/) = default;
     140           0 :   Weno& operator=(const Weno& /*rhs*/) = default;
     141           0 :   Weno(Weno&& /*rhs*/) = default;
     142           0 :   Weno& operator=(Weno&& /*rhs*/) = default;
     143           0 :   ~Weno() = default;
     144             : 
     145             :   // NOLINTNEXTLINE(google-runtime-references)
     146           0 :   void pup(PUP::er& p);
     147             : 
     148           0 :   using PackagedData = typename ConservativeVarsWeno::PackagedData;
     149           0 :   using package_argument_tags =
     150             :       typename ConservativeVarsWeno::package_argument_tags;
     151             : 
     152             :   /// \brief Package data for sending to neighbor elements
     153           1 :   void package_data(gsl::not_null<PackagedData*> packaged_data,
     154             :                     const Scalar<DataVector>& mass_density_cons,
     155             :                     const tnsr::I<DataVector, VolumeDim>& momentum_density,
     156             :                     const Scalar<DataVector>& energy_density,
     157             :                     const Mesh<VolumeDim>& mesh,
     158             :                     const std::array<double, VolumeDim>& element_size,
     159             :                     const OrientationMap<VolumeDim>& orientation_map) const;
     160             : 
     161           0 :   using limit_tags =
     162             :       tmpl::list<NewtonianEuler::Tags::MassDensityCons,
     163             :                  NewtonianEuler::Tags::MomentumDensity<VolumeDim>,
     164             :                  NewtonianEuler::Tags::EnergyDensity>;
     165           0 :   using limit_argument_tags = tmpl::list<
     166             :       domain::Tags::Mesh<VolumeDim>, domain::Tags::Element<VolumeDim>,
     167             :       domain::Tags::SizeOfElement<VolumeDim>,
     168             :       domain::Tags::DetInvJacobian<Frame::ElementLogical, Frame::Inertial>,
     169             :       evolution::dg::Tags::NormalCovectorAndMagnitude<VolumeDim>,
     170             :       ::hydro::Tags::EquationOfState<false, 2>>;
     171             : 
     172             :   /// \brief Limit the solution on the element
     173           1 :   bool operator()(
     174             :       gsl::not_null<Scalar<DataVector>*> mass_density_cons,
     175             :       gsl::not_null<tnsr::I<DataVector, VolumeDim>*> momentum_density,
     176             :       gsl::not_null<Scalar<DataVector>*> energy_density,
     177             :       const Mesh<VolumeDim>& mesh, const Element<VolumeDim>& element,
     178             :       const std::array<double, VolumeDim>& element_size,
     179             :       const Scalar<DataVector>& det_inv_logical_to_inertial_jacobian,
     180             :       const typename evolution::dg::Tags::NormalCovectorAndMagnitude<
     181             :           VolumeDim>::type& normals_and_magnitudes,
     182             :       const EquationsOfState::EquationOfState<false, 2>& equation_of_state,
     183             :       const std::unordered_map<DirectionalId<VolumeDim>, PackagedData,
     184             :                                boost::hash<DirectionalId<VolumeDim>>>&
     185             :           neighbor_data) const;
     186             : 
     187             :  private:
     188             :   template <size_t LocalDim>
     189             :   // NOLINTNEXTLINE(readability-redundant-declaration) false positive
     190           0 :   friend bool operator==(const Weno<LocalDim>& lhs, const Weno<LocalDim>& rhs);
     191             : 
     192           0 :   ::Limiters::WenoType weno_type_;
     193           0 :   NewtonianEuler::Limiters::VariablesToLimit vars_to_limit_;
     194           0 :   double neighbor_linear_weight_;
     195           0 :   std::optional<double> tvb_constant_;
     196           0 :   std::optional<double> kxrcf_constant_;
     197           0 :   bool apply_flattener_;
     198           0 :   bool disable_for_debugging_;
     199             :   // Note: conservative_vars_weno_ is always used for calls to package_data, and
     200             :   // is also used when limiting cons vars with the simple WENO algorithm. So we
     201             :   // construct conservative_vars_weno_ with the correct TVB constant when it is
     202             :   // used for limiting (precisely, when weno_type_ == SimpleWeno), and with a
     203             :   // dummy TVB constant value of NaN otherwise (weno_type_ == Hweno). This lets
     204             :   // us construct the conservative_vars_weno_ variable and use it for delegating
     205             :   // the package_data work even when the specialized limiter has no TVB constant
     206             :   // and is possible because package_data doesn't depend on the TCI.
     207           0 :   ConservativeVarsWeno conservative_vars_weno_;
     208             : };
     209             : 
     210             : template <size_t VolumeDim>
     211           0 : bool operator!=(const Weno<VolumeDim>& lhs, const Weno<VolumeDim>& rhs);
     212             : 
     213             : }  // namespace Limiters
     214             : }  // namespace NewtonianEuler