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-rw-r--r--Source/FieldSolver/FiniteDifferenceSolver/EvolveB.cpp33
-rw-r--r--Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/CylindricalYeeAlgorithm.H96
-rw-r--r--Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceSolver.H13
3 files changed, 73 insertions, 69 deletions
diff --git a/Source/FieldSolver/FiniteDifferenceSolver/EvolveB.cpp b/Source/FieldSolver/FiniteDifferenceSolver/EvolveB.cpp
index a1f35f903..c08dee04f 100644
--- a/Source/FieldSolver/FiniteDifferenceSolver/EvolveB.cpp
+++ b/Source/FieldSolver/FiniteDifferenceSolver/EvolveB.cpp
@@ -110,10 +110,9 @@ void FiniteDifferenceSolver::EvolveBCylindrical ( VectorField& Bfield,
auto const& Ez = Efield[2]->array(mfi);
// Extract stencil coefficients
- Real const* AMREX_RESTRICT coefs_x = stencil_coefs_x.dataPtr();
- int const n_coefs_x = stencil_coefs_x.size();
- Real const* AMREX_RESTRICT coefs_y = stencil_coefs_y.dataPtr();
- int const n_coefs_y = stencil_coefs_y.size();
+ Real const dr = m_dr;
+ Real const* AMREX_RESTRICT coefs_r = stencil_coefs_r.dataPtr();
+ int const n_coefs_r = stencil_coefs_r.size();
Real const* AMREX_RESTRICT coefs_z = stencil_coefs_z.dataPtr();
int const n_coefs_z = stencil_coefs_z.size();
@@ -126,12 +125,13 @@ void FiniteDifferenceSolver::EvolveBCylindrical ( VectorField& Bfield,
amrex::ParallelFor(tbr, tbt, tbz,
[=] AMREX_GPU_DEVICE (int i, int j, int k){
- Br(i, j, 0, 0) += dt * T_Algo::UpwardDz(Et, inv_dz, i, j, 0, 0); // Mode m = 0;
+ Real const r = rmin + i*dr; // r on nodal point (Br is nodal in r)
+ Br(i, j, 0, 0) += dt * T_Algo::UpwardDz(Et, coefs_z, n_coefs_z, i, j, 0, 0); // Mode m=0
for (int m=1; m<nmodes; m++) { // Higher-order modes
Br(i, j, 0, 2*m-1) += dt*( T_Algo::UpwardDz(Et, inv_dz, i, j, 0, 2*m-1)
- - m * T_Algo::DivideByR(Ez, r, dr, i, j, 0, 2*m )); // Real part
+ - m * T_Algo::DivideByR(Ez, r, dr, m, i, j, 0, 2*m )); // Real part
Br(i, j, 0, 2*m ) += dt*( T_Algo::UpwardDz(Et, inv_dz, i, j, 0, 2*m )
- + m * T_Algo::DivideByR(Ez, r, dr, i, j, 0, 2*m-1)); // Imaginary part
+ + m * T_Algo::DivideByR(Ez, r, dr, m, i, j, 0, 2*m-1)); // Imaginary part
}
// Ensure that Br remains 0 on axis (except for m=1)
if (r==0) { // On axis
@@ -144,13 +144,24 @@ void FiniteDifferenceSolver::EvolveBCylindrical ( VectorField& Bfield,
},
[=] AMREX_GPU_DEVICE (int i, int j, int k){
- Bt(i, j, 0, 0) += dt * T_Algo::UpwardDx(Ez, coefs_x, n_coefs_x, i, j, k)
- - dt * T_Algo::UpwardDz(Ex, coefs_z, n_coefs_z, i, j, k);
+ Bt(i, j, 0, 0) += dt*( T_Algo::UpwardDr(Ez, inv_dr, i, j, 0, 0)
+ - T_Algo::UpwardDz(Er, inv_dz, i, j, 0, 0)); // Mode m=0
+ for (int m=1 ; m<nmodes ; m++) { // Higher-order modes
+ Bt(i, j, 0, 2*m-1) += dt*( T_Algo::UpwardDr(Ez, inv_dr, i, j, 0, 2*m-1)
+ - T_Algo::UpwardDz(Er, inv_dz, i, j, 0, 2*m-1)); // Real part
+ Bt(i, j, 0, 2*m ) += dt*( T_Algo::UpwardDr(Ez, inv_dr, i, j, 0, 2*m )
+ - T_Algo::UpwardDz(Er, inv_dz, i, j, 0, 2*m )); // Imaginary part
+ }
},
[=] AMREX_GPU_DEVICE (int i, int j, int k){
- Bz(i, j, k) += dt * T_Algo::UpwardDy(Ex, coefs_y, n_coefs_y, i, j, k)
- - dt * T_Algo::UpwardDx(Ey, coefs_x, n_coefs_x, i, j, k);
+ Real const r = rmin + (i + 0.5)*dr; // r on a cell-centered grid (Bz is cell-centered in r)
+ Bz(i, j, 0, 0) += dt*( - T_Algo::UpwardDrr_over_r(Et, r, dr, i, j, 0, 0));
+ for (int m=1 ; m<nmodes ; m++) { // Higher-order modes
+ Bz(i, j, 0, 2*m-1) += dt*( m * Er(i, j, 0, 2*m )/r
+ - T_Algo::UpwardDrr_over_r(Et, r, dr, i, j, 0, 2*m-1)); // Real part
+ Bz(i, j, 0, 2*m ) += dt*(-m * Er(i, j, 0, 2*m-1)/r
+ - T_Algo::UpwardDrr_over_r(Et, r, dr, i, j, 0, 2*m )); // Imaginary part
}
);
diff --git a/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/CylindricalYeeAlgorithm.H b/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/CylindricalYeeAlgorithm.H
index 3f408479c..9258fdff4 100644
--- a/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/CylindricalYeeAlgorithm.H
+++ b/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceAlgorithms/CylindricalYeeAlgorithm.H
@@ -5,97 +5,77 @@
#include <AMReX_Array4.H>
#include <AMReX_Gpu.H>
-struct YeeAlgorithm {
+struct CylindricalYeeAlgorithm {
static void InitializeStencilCoefficients(
std::array<amrex::Real,3>& cell_size,
- amrex::Gpu::ManagedVector<amrex::Real>& stencil_coefs_x,
- amrex::Gpu::ManagedVector<amrex::Real>& stencil_coefs_y,
+ amrex::Gpu::ManagedVector<amrex::Real>& stencil_coefs_r,
amrex::Gpu::ManagedVector<amrex::Real>& stencil_coefs_z ) {
// Store the inverse cell size along each direction in the coefficients
- stencil_coefs_x.resize(1);
- stencil_coefs_x[0] = 1./cell_size[0];
- stencil_coefs_y.resize(1);
- stencil_coefs_y[0] = 1./cell_size[1];
+ stencil_coefs_r.resize(1);
+ stencil_coefs_r[0] = 1./cell_size[0]; // 1./dr
stencil_coefs_z.resize(1);
- stencil_coefs_z[0] = 1./cell_size[2];
+ stencil_coefs_z[0] = 1./cell_size[2]; // 1./dz
}
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
- static amrex::Real UpwardDx(
+ static amrex::Real UpwardDr(
amrex::Array4<amrex::Real> const& F,
- amrex::Real const* coefs_x, int const n_coefs_x,
- int const i, int const j, int const k ) {
+ amrex::Real const* coefs_r, int const n_coefs_r,
+ int const i, int const j, int const k, int const comp ) {
- amrex::Real inv_dx = coefs_x[0];
- return inv_dx*( F(i+1,j,k) - F(i,j,k) );
+ amrex::Real inv_dr = coefs_r[0];
+ return inv_dr*( F(i+1,j,k,comp) - F(i,j,k,comp) );
};
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
- static amrex::Real DownwardDx(
+ static amrex::Real DownwardDr(
amrex::Array4<amrex::Real> const& F,
- amrex::Real const* coefs_x, int const n_coefs_x,
- int const i, int const j, int const k ) {
+ amrex::Real const* coefs_r, int const n_coefs_r,
+ int const i, int const j, int const k, int const comp ) {
- amrex::Real inv_dx = coefs_x[0];
- return inv_dx*( F(i,j,k) - F(i-1,j,k) );
- };
-
- AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
- static amrex::Real UpwardDy(
- amrex::Array4<amrex::Real> const& F,
- amrex::Real const* coefs_y, int const n_coefs_y,
- int const i, int const j, int const k ) {
-
- #if defined WARPX_DIM_3D
- amrex::Real inv_dy = coefs_y[0];
- return inv_dy*( F(i,j+1,k) - F(i,j,k) );
- #elif (defined WARPX_DIM_XZ)
- return 0; // 2D Cartesian: derivative along y is 0
- #endif
- };
-
- AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
- static amrex::Real DownwardDy(
- amrex::Array4<amrex::Real> const& F,
- amrex::Real const* coefs_y, int const n_coefs_y,
- int const i, int const j, int const k ) {
-
- #if defined WARPX_DIM_3D
- amrex::Real inv_dy = coefs_y[0];
- return inv_dy*( F(i,j,k) - F(i,j-1,k) );
- #elif (defined WARPX_DIM_XZ)
- return 0; // 2D Cartesian: derivative along y is 0
- #endif
+ amrex::Real inv_dr = coefs_r[0];
+ return inv_dr*( F(i,j,k,comp) - F(i-1,j,k,comp) );
};
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
static amrex::Real UpwardDz(
amrex::Array4<amrex::Real> const& F,
amrex::Real const* coefs_z, int const n_coefs_z,
- int const i, int const j, int const k ) {
+ int const i, int const j, int const k, int const comp ) {
amrex::Real inv_dz = coefs_z[0];
- #if defined WARPX_DIM_3D
- return inv_dz*( F(i,j,k+1) - F(i,j,k) );
- #elif (defined WARPX_DIM_XZ)
- return inv_dz*( F(i,j+1,k) - F(i,j,k) );
- #endif
+ return inv_dz*( F(i,j+1,k,comp) - F(i,j,k,comp) );
};
AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
static amrex::Real DownwardDz(
amrex::Array4<amrex::Real> const& F,
amrex::Real const* coefs_z, int const n_coefs_z,
- int const i, int const j, int const k ) {
+ int const i, int const j, int const k, int const comp ) {
amrex::Real inv_dz = coefs_z[0];
- #if defined WARPX_DIM_3D
- return inv_dz*( F(i,j,k) - F(i,j,k-1) );
- #elif (defined WARPX_DIM_XZ)
- return inv_dz*( F(i,j,k) - F(i,j-1,k) );
- #endif
+ return inv_dz*( F(i,j,k,comp) - F(i,j-1,k,comp) );
+ };
+
+ AMREX_GPU_HOST_DEVICE AMREX_FORCE_INLINE
+ static amrex::Real DivideByR(
+ amrex::Array4<amrex::Real> const& F,
+ amrex::Real const r, int const dr, int const m,
+ int const i, int const j, int const k, int const comp) {
+
+ if (r != 0) {
+ return F(i,j,k,comp)/r;
+ } else { // r==0 ; singularity when dividing by r
+ if (m==1) {
+ // For m==1, F is linear in r, for small r
+ // Therefore, the formula below regularizes the singularity
+ return F(i+1,j,k,comp)/dr;
+ } else {
+ return 0;
+ }
+ }
};
};
diff --git a/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceSolver.H b/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceSolver.H
index c08810f85..deb89b1d6 100644
--- a/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceSolver.H
+++ b/Source/FieldSolver/FiniteDifferenceSolver/FiniteDifferenceSolver.H
@@ -27,12 +27,19 @@ class FiniteDifferenceSolver
m_fdtd_algo = fdtd_algo;
// Calculate coefficients of finite-difference stencil
+#ifdef WARPX_DIM_RZ
+ m_dr = cell_size[0];
+ if (fdtd_algo == MaxwellSolverAlgo::Yee){
+ CylindricalYeeAlgorithm::InitializeStencilCoefficients( cell_size,
+ stencil_coefs_r, stencil_coefs_z );
+#else
if (fdtd_algo == MaxwellSolverAlgo::Yee){
YeeAlgorithm::InitializeStencilCoefficients( cell_size,
stencil_coefs_x, stencil_coefs_y, stencil_coefs_z );
} else if (fdtd_algo == MaxwellSolverAlgo::CKC) {
CKCAlgorithm::InitializeStencilCoefficients( cell_size,
stencil_coefs_x, stencil_coefs_y, stencil_coefs_z );
+#endif
} else {
amrex::Abort("Unknown algorithm");
}
@@ -45,9 +52,15 @@ class FiniteDifferenceSolver
int m_fdtd_algo;
+#ifdef WARPX_DIM_RZ
+ amrex::Real m_dr;
+ amrex::Gpu::ManagedVector<amrex::Real> stencil_coefs_r;
+ amrex::Gpu::ManagedVector<amrex::Real> stencil_coefs_z;
+#else
amrex::Gpu::ManagedVector<amrex::Real> stencil_coefs_x;
amrex::Gpu::ManagedVector<amrex::Real> stencil_coefs_y;
amrex::Gpu::ManagedVector<amrex::Real> stencil_coefs_z;
+#endif
#ifdef WARPX_DIM_RZ
template< typename T_Algo >