Line data    Source code

       1           0 : // Distributed under the MIT License.
       2             : // See LICENSE.txt for details.
       3             : 
       4             : #pragma once
       5             : 
       6             : #include <cstddef>
       7             : 
       8             : #include "DataStructures/DataBox/Protocols/Mutator.hpp"
       9             : #include "DataStructures/DataVector.hpp"
      10             : #include "DataStructures/Tensor/Tensor.hpp"
      11             : #include "Domain/Tags.hpp"
      12             : #include "Evolution/Systems/CurvedScalarWave/Tags.hpp"
      13             : #include "Utilities/ProtocolHelpers.hpp"
      14             : 
      15           0 : namespace CurvedScalarWave::Worldtube::Initialization {
      16             : 
      17             : /*!
      18             :  * \ingroup InitializationGroup
      19             :  * \brief Initializes the constraint damping parameters \f$\gamma_1\f$ and
      20             :  * \f$\gamma_2\f$.
      21             :  *
      22             :  * \details The constraint damping parameters  of the CurvedScalarWave system
      23             :  * are initialized according to a Gaussian
      24             :  * \f{align*}
      25             :  *  \gamma_1 &= 0 \\
      26             :  *  \gamma_2 &= A e^{-(\sigma r)^2 } + c,
      27             :  * \f}
      28             :  * where \f$r = \sqrt{\delta_{ij} x^i x^j}\f$ and with \f$A = 10\f$, \f$\sigma =
      29             :  * 10^{-1}\f$, \f$c = 10^{-4}\f$. These values were experimentally found to
      30             :  * ensure a stable evolution when using the worldtube scheme.
      31             :  *
      32             :  *  DataBox changes:
      33             :  * - Adds:
      34             :  *   * `CurvedScalarWave::Tags::ConstraintGamma1`
      35             :  *   * `CurvedScalarWave::Tags::ConstraintGamma2`
      36             :  * - Removes: nothing
      37             :  * - Modifies: nothing
      38             :  */
      39             : template <size_t Dim>
      40           1 : struct InitializeConstraintDampingGammas
      41             :     : tt::ConformsTo<db::protocols::Mutator> {
      42           0 :   using return_tags = tmpl::list<CurvedScalarWave::Tags::ConstraintGamma1,
      43             :                                  CurvedScalarWave::Tags::ConstraintGamma2>;
      44           0 :   using argument_tags =
      45             :       tmpl::list<domain::Tags::Coordinates<Dim, Frame::Inertial>>;
      46           0 :   using simple_tags = return_tags;
      47           0 :   using compute_tags = tmpl::list<>;
      48           0 :   using simple_tags_from_options = tmpl::list<>;
      49           0 :   using const_global_cache_tags = tmpl::list<>;
      50           0 :   using mutable_global_cache_tags = tmpl::list<>;
      51           0 :   static void apply(
      52             :       const gsl::not_null<Scalar<DataVector>*> gamma1,
      53             :       const gsl::not_null<Scalar<DataVector>*> gamma2,
      54             :       const tnsr::I<DataVector, Dim, Frame::Inertial>& inertial_coords);
      55             : };
      56             : }  // namespace CurvedScalarWave::Worldtube::Initialization