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/* Copyright 2020
*
* This file is part of WarpX.
*
* License: BSD-3-Clause-LBNL
*/
#include "WarpX.H"
#include "Utils/WarpXAlgorithmSelection.H"
#ifdef WARPX_DIM_RZ
# include "FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/CylindricalYeeAlgorithm.H"
#else
# include "FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/CartesianYeeAlgorithm.H"
# include "FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/CartesianCKCAlgorithm.H"
# include "FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/CartesianNodalAlgorithm.H"
#endif
/**
* Determine the timestep of the simulation. */
void
WarpX::ComputeDt ()
{
// Determine
const amrex::Real* dx = geom[max_level].CellSize();
amrex::Real deltat = 0.;
if (maxwell_solver_id == MaxwellSolverAlgo::PSATD) {
// Computation of dt for spectral algorithm
#if (defined WARPX_DIM_RZ)
// - In RZ geometry: dz/c
deltat = cfl * dx[1]/PhysConst::c;
#elif (defined WARPX_DIM_XZ)
// - In Cartesian 2D geometry: determined by the minimum cell size in all direction
deltat = cfl * std::min( dx[0], dx[1] )/PhysConst::c;
#else
// - In Cartesian 3D geometry: determined by the minimum cell size in all direction
deltat = cfl * std::min(dx[0], std::min(dx[1], dx[2])) / PhysConst::c;
#endif
} else {
// Computation of dt for FDTD algorithm
#ifdef WARPX_DIM_RZ
// - In RZ geometry
if (maxwell_solver_id == MaxwellSolverAlgo::Yee) {
deltat = cfl * CylindricalYeeAlgorithm::ComputeMaxDt(dx, n_rz_azimuthal_modes);
#else
// - In Cartesian geometry
if (do_nodal) {
deltat = cfl * CartesianNodalAlgorithm::ComputeMaxDt(dx);
} else if (maxwell_solver_id == MaxwellSolverAlgo::Yee) {
deltat = cfl * CartesianYeeAlgorithm::ComputeMaxDt(dx);
} else if (maxwell_solver_id == MaxwellSolverAlgo::CKC) {
deltat = cfl * CartesianCKCAlgorithm::ComputeMaxDt(dx);
#endif
} else {
amrex::Abort("ComputeDt: Unknown algorithm");
}
}
dt.resize(0);
dt.resize(max_level+1,deltat);
if (do_subcycling) {
for (int lev = max_level-1; lev >= 0; --lev) {
dt[lev] = dt[lev+1] * refRatio(lev)[0];
}
}
if (do_electrostatic != ElectrostaticSolverAlgo::None) {
dt[0] = const_dt;
}
for (int lev=0; lev <= max_level; lev++) {
const amrex::Real* dx_lev = geom[lev].CellSize();
amrex::Print()<<"Level "<<lev<<": dt = "<<dt[lev]
<<" ; dx = "<<dx_lev[0]
#if (defined WARPX_DIM_XZ) || (defined WARPX_DIM_RZ)
<<" ; dz = "<<dx_lev[1]<<'\n';
#elif (defined WARPX_DIM_3D)
<<" ; dy = "<<dx_lev[1]
<<" ; dz = "<<dx_lev[2]<<'\n';
#endif
}
}
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