/* Copyright 2019-2020 Maxence Thevenet, Remi Lehe, Edoardo Zoni * * This file is part of WarpX. * * License: BSD-3-Clause-LBNL */ #ifndef WARPX_SPECTRAL_SOLVER_H_ #define WARPX_SPECTRAL_SOLVER_H_ #include "SpectralSolver_fwd.H" #include "SpectralAlgorithms/SpectralBaseAlgorithm.H" #include "SpectralFieldData.H" #include #include #include #include #include #include #ifdef WARPX_USE_PSATD /** * \brief Top-level class for the electromagnetic spectral solver * * Stores the field in spectral space, and has member functions * to Fourier-transform the fields between real space and spectral space * and to update fields in spectral space over one time step. */ class SpectralSolver { public: /** * \brief Constructor of the class SpectralSolver * * Select the spectral algorithm to be used, allocate the corresponding coefficients * for the discrete field update equations, and prepare the structures that store * the fields in spectral space. * * \param[in] lev mesh refinement level * \param[in] realspace_ba BoxArray in real space * \param[in] dm DistributionMapping for the given BoxArray * \param[in] norder_x spectral order along x * \param[in] norder_y spectral order along y * \param[in] norder_z spectral order along z * \param[in] nodal whether the spectral solver is applied to a nodal or staggered grid * \param[in] v_galilean three-dimensional vector containing the components of the Galilean * velocity for the standard or averaged Galilean PSATD solvers * \param[in] v_comoving three-dimensional vector containing the components of the comoving * velocity for the comoving PSATD solver * \param[in] dx AMREX_SPACEDIM-dimensional vector containing the cell sizes along each direction * \param[in] dt time step for the analytical integration of Maxwell's equations * \param[in] pml whether the boxes in the given BoxArray are PML boxes * \param[in] periodic_single_box whether there is only one periodic single box * (no domain decomposition) * \param[in] update_with_rho whether rho is used in the field update equations * \param[in] fft_do_time_averaging whether the time averaging algorithm is used * \param[in] J_linear_in_time whether to use two currents computed at the beginning and * the end of the time interval (instead of using one current * compute at half time) * \param[in] dive_cleaning whether to use div(E) cleaning to account for errors in Gauss law * (new field F in the field update equations) * \param[in] divb_cleaning whether to use div(B) cleaning to account for errors in magnetic Gauss law * (new field G in the field update equations) */ SpectralSolver (const int lev, const amrex::BoxArray& realspace_ba, const amrex::DistributionMapping& dm, const int norder_x, const int norder_y, const int norder_z, const bool nodal, const amrex::IntVect& fill_guards, const amrex::Array& v_galilean, const amrex::Array& v_comoving, const amrex::RealVect dx, const amrex::Real dt, const bool pml = false, const bool periodic_single_box = false, const bool update_with_rho = false, const bool fft_do_time_averaging = false, const bool J_linear_in_time = false, const bool dive_cleaning = false, const bool divb_cleaning = false); /** * \brief Transform the component `i_comp` of MultiFab `mf` * to spectral space, and store the corresponding result internally * (in the spectral field specified by `field_index`) */ void ForwardTransform( const int lev, const amrex::MultiFab& mf, const int field_index, const int i_comp=0 ); /** * \brief Transform spectral field specified by `field_index` back to * real space, and store it in the component `i_comp` of `mf` */ void BackwardTransform( const int lev, amrex::MultiFab& mf, const int field_index, const int i_comp=0 ); /** * \brief Update the fields in spectral space, over one timestep */ void pushSpectralFields(); /** * \brief Public interface to call the member function ComputeSpectralDivE * of the base class SpectralBaseAlgorithm from objects of class SpectralSolver */ void ComputeSpectralDivE ( const int lev, const std::array,3>& Efield, amrex::MultiFab& divE ) { algorithm->ComputeSpectralDivE( lev, field_data, Efield, divE ); } /** * \brief Public interface to call the virtual function \c CurrentCorrection, * defined in the base class SpectralBaseAlgorithm and possibly overridden * by its derived classes (e.g. PsatdAlgorithm, GalileanAlgorithm), from * objects of class SpectralSolver through the private unique pointer \c algorithm * * \param[in,out] current three-dimensional array of unique pointers to MultiFab * storing the three components of the current density * \param[in] rho unique pointer to MultiFab storing the charge density */ void CurrentCorrection ( const int lev, std::array,3>& current, const std::unique_ptr& rho ) { algorithm->CurrentCorrection( lev, field_data, current, rho ); } /** * \brief Public interface to call the virtual function \c VayDeposition, * declared in the base class SpectralBaseAlgorithm and defined in its * derived classes, from objects of class SpectralSolver through the private * unique pointer \c algorithm. * * \param[in,out] current Array of unique pointers to \c MultiFab storing * the three components of the current density */ void VayDeposition (const int lev, std::array,3>& current) { algorithm->VayDeposition(lev, field_data, current); } /** * \brief Copy spectral data from component \c src_comp to component \c dest_comp * of \c field_data.fields. * * \param[in] src_comp component of the source FabArray from which the data are copied * \param[in] dest_comp component of the destination FabArray where the data are copied */ void CopySpectralDataComp (const int src_comp, const int dest_comp) { // The last two arguments represent the number of components and // the number of ghost cells to perform this operation Copy(field_data.fields, field_data.fields, src_comp, dest_comp, 1, 0); } /** * \brief Set to zero the data on component \c icomp of \c field_data.fields * * \param[in] icomp component of the FabArray where the data are set to zero */ void ZeroOutDataComp (const int icomp) { // The last argument represents the number of components to perform this operation field_data.fields.setVal(0., icomp, 1); } /** * \brief Scale the data on component \c icomp of \c field_data.fields * by a given scale factor * * \param[in] icomp component of the FabArray where the data are scaled * \param[in] scale_factor scale factor to use for scaling */ void ScaleDataComp (const int icomp, const amrex::Real scale_factor) { // The last argument represents the number of components to perform this operation field_data.fields.mult(scale_factor, icomp, 1); } protected: amrex::IntVect m_fill_guards; private: void ReadParameters (); // Store field in spectral space and perform the Fourier transforms SpectralFieldData field_data; // Defines field update equation in spectral space and the associated coefficients. // SpectralBaseAlgorithm is a base class; this pointer is meant to point // to an instance of a sub-class defining a specific algorithm std::unique_ptr algorithm; }; #endif // WARPX_USE_PSATD #endif // WARPX_SPECTRAL_SOLVER_H_