GE REDUCED PROBLEM WITH DIFFERENT INITIAL CONDITIONS 2
The reduced problem is from
Lawler & Kortshagen, J. Phys D: Appl Phys 32, pp 3188-3198 (1999),
"Self-consistent Monte Carlo simulations of the positive column of gas
discharges."
The reduced problem using the Lawler and Kortshagen cross-sectional
data was run on a 600 MHz Pentium III machine with 5 times the initial density
of the previous run in
Reduced Problem with L&K X-secs
The simulation starts off with initial Bessel function
electron and ion density profiles with axial density = 8.2e9/cc.
The following is a link to the input file:
Input File.
The simulation was run for 24 microsecs. Equilibrium was reached at
about 22 microsecs
as can seen from the Average Density(t) and Ez(t) diagnostics below.
Increasing the initial density by a factor of 5 had no effect on the
final equilibrium state. But the overall time to equilibrium increased
from 5 microsecs to 22 microsecs. Again, agreement is good between the
expected and XPDC1 output.
INPUTS
Gas is argon with model cross sections (one lumped excited state)
R=1 cm
Gas temperature = 273K
Gas pressure = 2.83 mTorr (2.83e-3 Torr)
Gas density = 1e14/cc (important!)
Axial current = 15.2 mA
EXPECTED OUTPUT (from Lawler and Kortshagen paper)
Ez=1.0 V/cm (from Table 1)
Electron average energy on axis = 14.7 V (from Table 1)
Electron density on axis = 1.64e9/cc (from Table 1)
Wall potential = 37 V (by inspection of Figure 1)
XPDC1 OUTPUT
Ez=0.73 V/cm
Electron average energy on axis = 14 V
Electron density on axis = 1.6e9/cc
Wall potential = 32 V
