Mesh¶
There are two output files containing mesh parameters (the 5D mesh consists of a 3D unstructured triangular mesh in configuration space and a 2D structured rectangular grid in velocity space): xgc.f0.mesh.bp and xgc.mesh.bp.
Remarks
These files contain quantities that can be useful to calculate various averages.
# flux surfaces here includes the scrape-off layer, i.e. the open field-line region.
xgc.f0.mesh.bp
Printed when: sml_f0_grid=.true.. Output frequency: once at start/restart.
Output |
Dimension |
Units |
Description |
---|---|---|---|
f0_T_ev |
\(N_{\mathrm{species}}~\times\)
# 3D mesh nodes
|
\(\mathrm{eV}\) |
Temperature at start in all configuration space vertices for electrons (0) and ions (1). |
f0_den |
# 3D mesh nodes |
\({\mathrm{m}}^{-3}\) |
Density at start in all configuration space vertices. Is n_e = n_i assumed? |
f0_dsmu |
Scalar |
\(v_{Ts} = \sqrt{\frac{T_s}{m_s}}\) |
\(\Delta v_{\perp}\) in the 2D velocity grid of species \(s\). |
f0_dvp |
Scalar |
\(v_{Ts} = \sqrt{\frac{T_s}{m_s}}\) |
\(\Delta v_{\|}\) in the 2D velocity grid of species \(s\). |
f0_grid_vol_vonly |
\(N_{\mathrm{species}}~\times\)
# 3D mesh nodes
|
Units |
Prefactor for calculating velocity space moments. \(= \left( T_s/\sqrt{2 \pi} \right) \times \) \(\times\) |
f0_nmu |
Scalar |
Positive integer |
Number of grid points in \(v_{\perp}\) in the 2D velocity grid is f0_nmu + 1. Same as input parameter |
f0_nvp |
Scalar |
Positive integer |
Number of grid points in \(v_{\|}\) in the 2D velocity grid is 2 \(\times\) f0_nvp + 1. Same as input parameter |
f0_smu_max |
Scalar |
\(v_{Ts} = \sqrt{\frac{T_s}{m_s}}\) |
Maximum \(v_{\perp}\) in the 2D velocity grid (minimum is \(0\)). Same as input parameter |
f0_vp_max |
Scalar |
\(v_{Ts} = \sqrt{\frac{T_s}{m_s}}\) |
Maximum/minimum \(v_{\|}\) (minimum with minus sign) in the 2D velocity grid. Same as input parameter |
gradpsi |
# 3D mesh nodes
\(\times\) 2
|
Units |
Description |
inode1m1 |
Scalar |
Units |
Description |
n_n |
Scalar |
Positive integer |
Number of 3D mesh nodes. |
nb_curl_nb |
# 3D mesh nodes |
Units |
Description |
ndata |
Scalar |
Positive integer |
Description |
nsp |
Scalar |
Positive integer |
Number of kinetic species. |
v_curv |
# 3D mesh nodes
\(\times\) 3
|
Units |
Description |
v_gradb |
# 3D mesh nodes
\(\times\) 3
|
Units |
Description |
xgc.mesh.bp
Printed when: always. Output frequency: once at start/restart.
Output |
Dimension |
Units |
Description |
---|---|---|---|
PEST_angle |
# poloidal planes * \(\times\)
# planar mesh nodes
|
Radians |
PEST coordinate on the mesh nodes (only written for stellarator simulations). |
VMEC_angle |
# poloidal planes * \(\times\)
# planar mesh nodes
|
Radians |
VMEC coordinate on the mesh nodes (only written for stellarator simulations). |
delta_phi |
Scalar |
Radians |
Toroidal angle increment for each poloidal plane. |
epsilon |
# flux surfaces |
Normalized |
Inverse aspect ratio rmin/rmaj for the flux surface. |
ff_1dp_p |
2 \(\times\) # 3D mesh nodes \(\times\) 3 |
Units |
Description |
ff_hdp_p |
2 \(\times\) # 3D mesh nodes \(\times\) 3 |
Units |
Description |
grid_nwall |
Scalar |
Positive integer |
Number of nodes that make up the boundary of the domain (and represent the wall). |
grid_wall_nodes |
nwall |
Positive integer |
Node index for each wall node. Currently not “ordered”, but in the order specified in .node file. |
m_max_surf |
# flux surfaces |
Positive integer |
Maximum resolvable poloidal mode number on each flux surface. Defined by field-following alignment when generating the mesh. |
mapping |
# 3D mesh triangles \(\times\) 3 \(\times\) 2 |
m |
Defines coordinates of triangle vertices. |
n_geo |
Scalar |
Positive integer |
Number of flux surfaces. Same as |
n_n |
Scalar |
Positive integer |
Number of 2D mesh nodes. |
n_t |
Scalar |
Positive integer |
Number of 2D mesh triangles. |
nd_connect_list |
# poloidal planes * \(\times\)
# 3D mesh triangles
\(\times\) 3
|
Integer |
Defines triangular mesh on each poloidal plane (similar to, but indexed differently from .ele file). First index is triangle index and the second index is over the three nodes that make up the triangle’s vertices. These are labelled by the index of the mesh node (from .node file). Index of nodes counts starting from zero. |
nextnode |
# 3D mesh nodes |
Units |
Description |
node_vol |
# 3D mesh nodes |
\(\mathrm{m}^{3}\) |
Spatial volume of the 3D mesh node. Volume of whole torus is |
node_vol_ff0 |
# 3D mesh nodes |
Units |
Description |
node_vol_ff0_l |
# 3D mesh nodes |
Units |
Description |
node_vol_ff0_r |
# 3D mesh nodes |
Units |
Description |
node_vol_ff1 |
# 3D mesh nodes |
Units |
Description |
node_vol_ff1_l |
# 3D mesh nodes |
Units |
Description |
node_vol_ff1_r |
# 3D mesh nodes |
Units |
Description |
node_vol_nearest |
# 3D mesh nodes |
\(\mathrm{m}^{3}\) |
Description |
nphi |
Scalar |
Positive integer |
Number of poloidal planes \(N_{\mathrm{planes}}\) (only written for stellarator simulations). |
nsurf |
Scalar |
Positive integer |
Number of flux surfaces. |
one_per_dx |
2 \(\times\) # 3D mesh nodes |
Units |
Description |
psi |
# 3D mesh nodes |
Weber/rad |
Toroidal magnetic flux for the flux surface that the node is on. |
psi_surf |
# flux surfaces |
Weber/rad |
Toroidal magnetic flux for the flux surface. |
qsafety |
# flux surfaces |
Normalized |
Safety factor \(q\) for the flux surface. |
region |
# 2D mesh nodes |
Integer value |
Region number for each node. 1 for core, 2 for SOL, etc. |
rmaj |
# flux surfaces |
m |
Major radius of flux surface. |
rmin |
# flux surfaces |
m |
Minor radius of flux surface |
rz |
# poloidal planes * \(\times\)
# 3D mesh nodes
\(\times\) 2
|
Meters |
Defines the spatial location in the poloidal plane for each mesh node. First index defines the node. Second index is the \((R,Z)\) coordinate of the node. |
surf_arc_len |
# flux surfaces |
m |
Poloidal arc-length of the complete flux surface. |
surf_idx |
# flux surfaces
\(\times\) surf_maxlen
|
Positive integer |
Node index for each node on a flux surface. First index is flux surface label and second index is the node on the flux surface. Nodes counted from 1. Filled with zeros beyond |
surf_len |
# flux surfaces |
Positive integer |
Number of nodes in each flux surface. |
surf_maxlen |
Scalar |
Positive integer |
The maximum number of nodes on any flux surface. Used for indexing surf_idx. |
theta |
# 3D mesh nodes |
Normalized |
Poloidal coordinate. |
tr_area |
# 3D mesh triangles |
Units |
Triangle areas. |
trapped |
# flux surfaces |
Normalized |
Trapped particle fraction for flux surface. |
wedge_angle |
Scalar |
Radians |
Torus wedge angle or toroidal periodicity. |
wedge_n |
Scalar |
Positive integer |
Torus wedge number or toroidal periodicity (only written for stellarator simulations). |
* Dimension only for stellarator simulations.