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Diffstat (limited to 'Source/FieldSolver/SpectralSolver/SpectralAlgorithms/PsatdAlgorithmPmlRZ.cpp')
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diff --git a/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/PsatdAlgorithmPmlRZ.cpp b/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/PsatdAlgorithmPmlRZ.cpp new file mode 100644 index 000000000..16f4f1e37 --- /dev/null +++ b/Source/FieldSolver/SpectralSolver/SpectralAlgorithms/PsatdAlgorithmPmlRZ.cpp @@ -0,0 +1,177 @@ +/* Copyright 2021 David Grote + * + * This file is part of WarpX. + * + * License: BSD-3-Clause-LBNL + */ +#include "PsatdAlgorithmPmlRZ.H" +#include "FieldSolver/SpectralSolver/SpectralHankelTransform/HankelTransform.H" +#include "Utils/WarpXConst.H" +#include "Utils/WarpXProfilerWrapper.H" +#include "WarpX.H" + +#include <cmath> + +using amrex::operator""_rt; + + +/* \brief Initialize coefficients for the update equation */ +PsatdAlgorithmPmlRZ::PsatdAlgorithmPmlRZ (SpectralKSpaceRZ const & spectral_kspace, + amrex::DistributionMapping const & dm, + const SpectralFieldIndex& spectral_index, + int const n_rz_azimuthal_modes, int const norder_z, + bool const nodal, amrex::Real const dt) + // Initialize members of base class + : SpectralBaseAlgorithmRZ(spectral_kspace, dm, spectral_index, norder_z, nodal), + m_spectral_index(spectral_index), + m_dt(dt) +{ + // Allocate the arrays of coefficients + amrex::BoxArray const & ba = spectral_kspace.spectralspace_ba; + C_coef = SpectralRealCoefficients(ba, dm, n_rz_azimuthal_modes, 0); + S_ck_coef = SpectralRealCoefficients(ba, dm, n_rz_azimuthal_modes, 0); + + coefficients_initialized = false; +} + +/* Advance the E and B field in spectral space (stored in `f`) + * over one time step */ +void +PsatdAlgorithmPmlRZ::pushSpectralFields (SpectralFieldDataRZ & f) +{ + + if (not coefficients_initialized) { + // This is called from here since it needs the kr values + // which can be obtained from the SpectralFieldDataRZ + InitializeSpectralCoefficients(f); + coefficients_initialized = true; + } + + const SpectralFieldIndex& Idx = m_spectral_index; + + // Loop over boxes + for (amrex::MFIter mfi(f.fields); mfi.isValid(); ++mfi){ + + amrex::Box const & bx = f.fields[mfi].box(); + + // Extract arrays for the fields to be updated + amrex::Array4<Complex> const& fields = f.fields[mfi].array(); + // Extract arrays for the coefficients + amrex::Array4<const amrex::Real> const& C_arr = C_coef[mfi].array(); + amrex::Array4<const amrex::Real> const& S_ck_arr = S_ck_coef[mfi].array(); + + // Extract pointers for the k vectors + HankelTransform::RealVector const & kr_modes = f.getKrArray(mfi); + amrex::Real const* kr_arr = kr_modes.dataPtr(); + int const nr = bx.length(0); + + // Loop over indices within one box + // Note that k = 0 + int const modes = f.n_rz_azimuthal_modes; + amrex::ParallelFor(bx, modes, + [=] AMREX_GPU_DEVICE(int i, int j, int k, int mode) noexcept + { + + // All of the fields of each mode are grouped together + int const Ep_m_pml = Idx.Er_pml + Idx.n_fields*mode; + int const Em_m_pml = Idx.Et_pml + Idx.n_fields*mode; + int const Bp_m_pml = Idx.Br_pml + Idx.n_fields*mode; + int const Bm_m_pml = Idx.Bt_pml + Idx.n_fields*mode; + int const Ez_m = Idx.Ez + Idx.n_fields*mode; + int const Bz_m = Idx.Bz + Idx.n_fields*mode; + + // Record old values of the fields to be updated + Complex const Ep_old_pml = fields(i,j,k,Ep_m_pml); + Complex const Em_old_pml = fields(i,j,k,Em_m_pml); + Complex const Bp_old_pml = fields(i,j,k,Bp_m_pml); + Complex const Bm_old_pml = fields(i,j,k,Bm_m_pml); + Complex const Ez_old = fields(i,j,k,Ez_m); + Complex const Bz_old = fields(i,j,k,Bz_m); + + // k vector values, and coefficients + // The k values for each mode are grouped together + int const ir = i + nr*mode; + amrex::Real const kr = kr_arr[ir]; + + constexpr amrex::Real c2 = PhysConst::c*PhysConst::c; + Complex const I = Complex{0._rt,1._rt}; + amrex::Real const C = C_arr(i,j,k,mode); + amrex::Real const S_ck = S_ck_arr(i,j,k,mode); + + // Update E (see WarpX online documentation: theory section) + fields(i,j,k,Ep_m_pml) = C*Ep_old_pml + + S_ck*(-c2*I*kr/2._rt*Bz_old); + fields(i,j,k,Em_m_pml) = C*Em_old_pml + + S_ck*(-c2*I*kr/2._rt*Bz_old); + // Update B (see WarpX online documentation: theory section) + fields(i,j,k,Bp_m_pml) = C*Bp_old_pml + - S_ck*(-I*kr/2._rt*Ez_old); + fields(i,j,k,Bm_m_pml) = C*Bm_old_pml + - S_ck*(-I*kr/2._rt*Ez_old); + + }); + } +} + +void PsatdAlgorithmPmlRZ::InitializeSpectralCoefficients (SpectralFieldDataRZ const & f) +{ + + // Fill them with the right values: + // Loop over boxes and allocate the corresponding coefficients + // for each box owned by the local MPI proc + for (amrex::MFIter mfi(f.fields); mfi.isValid(); ++mfi){ + + amrex::Box const & bx = f.fields[mfi].box(); + + // Extract pointers for the k vectors + amrex::Real const* const modified_kz = modified_kz_vec[mfi].dataPtr(); + + // Extract arrays for the coefficients + amrex::Array4<amrex::Real> const& C = C_coef[mfi].array(); + amrex::Array4<amrex::Real> const& S_ck = S_ck_coef[mfi].array(); + + HankelTransform::RealVector const & kr_modes = f.getKrArray(mfi); + amrex::Real const* kr_arr = kr_modes.dataPtr(); + int const nr = bx.length(0); + amrex::Real const dt = m_dt; + + // Loop over indices within one box + int const modes = f.n_rz_azimuthal_modes; + amrex::ParallelFor(bx, modes, + [=] AMREX_GPU_DEVICE(int i, int j, int k, int mode) noexcept + { + // Calculate norm of vector + int const ir = i + nr*mode; + amrex::Real const kr = kr_arr[ir]; + amrex::Real const kz = modified_kz[j]; + amrex::Real const k_norm = std::sqrt(kr*kr + kz*kz); + + // Calculate coefficients + constexpr amrex::Real c = PhysConst::c; + if (k_norm != 0._rt){ + C(i,j,k,mode) = std::cos(c*k_norm*dt); + S_ck(i,j,k,mode) = std::sin(c*k_norm*dt)/(c*k_norm); + } else { // Handle k_norm = 0, by using the analytical limit + C(i,j,k,mode) = 1._rt; + S_ck(i,j,k,mode) = dt; + } + }); + } +} + +void +PsatdAlgorithmPmlRZ::CurrentCorrection (const int /* lev */, + SpectralFieldDataRZ& /* field_data */, + std::array<std::unique_ptr<amrex::MultiFab>,3>& /* current */, + const std::unique_ptr<amrex::MultiFab>& /* rho */) +{ + amrex::Abort("Current correction not implemented in RZ geometry PML"); +} + +void +PsatdAlgorithmPmlRZ::VayDeposition (const int /* lev */, + SpectralFieldDataRZ& /*field_data*/, + std::array<std::unique_ptr<amrex::MultiFab>,3>& /*current*/) +{ + amrex::Abort("Vay deposition not implemented in RZ geometry PML"); +} |