Sheath And Wall Diagnostics

This page is generated from in-code XGC I/O metadata by utils/python/document_outputs.py.

Sheath, wall-loss, heat-flux, and Gyraze surrogate sheath diagnostic outputs.

xgc.heatdiag*.bp

Variable	Units	Description
ds	m^2	Surface area of the wall-curve segments on which the heat load is sampled.
gstep	Non-negative integer	XGC global simulation time step for this heat diagnostic output slice.
nphi	Positive integer	Number of toroidal mesh planes \(N_{\mathrm{planes}}\).
nseg	Positive integer	Number of wall segments on which the heat load is sampled.
nseg1	Positive integer	Number of wall segments on which the heat load is sampled plus one bin for unassigned wall crossings.
psamples	Positive integer	Number of sampling points in normalized poloidal flux (psi).
psi	T m^2	Poloidal magnetic flux \(\psi/(2\pi)\) at the heat load sampling points.
psi	T m^2	Poloidal magnetic flux \(\psi/(2\pi)\).
r	m	Radial coordinates of the sampling points.
rsamples	Positive integer	Number of sampling points in R-direction.
section	Positive integer	Number of sections in which the divertor heat load is sampled.
sp_name + "_distance"	m	Displacement of the marker particles in the time step they left the mesh projected to the midplane of the wedge they were in.
sp_name + "_distance_psi"	m	Displacement of the marker particles in the time step they left the mesh projected to the midplane of the wedge they were in (binned with respect to the normalized poloidal flux).
sp_name + "_number"	particle count	Number of plasma particles (not markers) hitting each sampling point (in RZ-coordinates). Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
sp_name + "_number"	particle count	Number of plasma particles (not markers) hitting each wall segment; nseg1 includes bin 0 for particle wall crossings that could not be assigned to any segment of the wall polygon. Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
sp_name + "_number_psi"	particle count	Number of plasma particles (not markers) hitting each sampling point (in psi). Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
sp_name + "_para_energy"	J	Parallel kinetic energy hitting each sampling point (in RZ-coordinates). Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
sp_name + "_para_energy"	J	Parallel kinetic energy hitting each wall segment; nseg1 includes bin 0 for particle wall crossings that could not be assigned to any segment of the wall polygon. Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
sp_name + "_para_energy_psi"	J	Parallel kinetic energy hitting each sampling point (in psi). Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
sp_name + "_perp_energy"	J	Perpendicular kinetic energy hitting each sampling point (in RZ-coordinates). Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
sp_name + "_perp_energy"	J	Perpendicular kinetic energy hitting each wall segment; nseg1 includes bin 0 for particle wall crossings that could not be assigned to any segment of the wall polygon. Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
sp_name + "_perp_energy_psi"	J	Perpendicular kinetic energy hitting each sampling point (in psi). Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
sp_name + "_potential"	V	Sheath potential at each sampling point in RZ coordinates.
sp_name + "_potential"	V	Sheath potential at the wall segments on which the heat load is sampled.
sp_name + "_potential_psi"	V	Sheath potential at each sampling point in normalized poloidal flux (psi). Data is accumulated over all time steps between two subsequent heat diagnostic outputs.
strike_angle	rad	Angle of the magnetic field relative to the wall surface normal.
time	s	Simulation time of step in seconds.
tindex	Positive integer	Index of the current heat load diagnostic time slice.
z	m	Z-coordinates of the sampling points.
zsamples	Positive integer	Number of sampling points in Z-direction.

xgc.sheathdiag.bp

Variable	Units	Description
gstep	Non-negative integer	XGC global simulation time step for this sheath output slice.
gyraze_converged_count	1	Number of Gyraze surrogate calls classified as converged at each wall node
gyraze_cutoff_factor_avg	1	Average Gyraze sheath cutoff scaling factor at each wall node over this diagnostic interval
gyraze_cutoff_factor_count	Non-negative integer	Number of electron sheath hits included in gyraze_cutoff_factor_avg at each wall node
gyraze_fallback_count	1	Number of Gyraze surrogate calls that fell back to the original cutoff factor at each wall node
gyraze_potential_avg	V	Average local sheath potential passed to Gyraze at each wall node over this diagnostic interval
gyraze_unconverged_count	1	Number of Gyraze surrogate calls classified as unconverged and evaluated with the full MPE model at each wall node
nwall	Positive integer	Number of vertices in the wall polygon.
sheath_ilost	C	Total ion charge lost to the wall in the time step preceding the output time slice.
sheath_lost	C	Total charge lost to the wall in the time step preceding the output time slice.
sheath_nphi	Positive integer	Number of toroidal mesh planes resolved by the sheath calculation; toroidal angle spacing depends on nphi and wedge_n in xgc.mesh.bp: \(\Delta\phi = 2\pi/(N_{\phi} N_{\mathrm{wedge}})\).
sheath_pot	V	Sheath potential drop (from magnetic pre-sheath to the grounded wall) evaluated by the logical sheath module.
time	s	Simulation time of this sheath output slice.
tindex	Positive integer	Index of this sheath diagnostic output time slice. Values: 1, 2, …, # outputs.

xgc.gyraze.bp

Variable	Units	Description
bfield_impact_angle	rad	Magnetic grazing angle relative to the local wall surface at wall nodes in xgc.mesh.bp grid_wall_nodes ordering
grid_nwall	Positive integer	Number of wall nodes in xgc.gyraze.bp, matching grid_wall_nodes ordering in xgc.mesh.bp.