[Archive] thruster plume time steps

Message by Mehmet Balta:
Hi,
I am trying to verify SPT100 thruster plumes. However I have troubles with the convergence of current density values.
GEO worst case electron number density is 3e6 ! m3 !. However the electron number density for the thruster plume is significantly larger than that (3e15 ! m3 !).
As you know the formula to set the individual time step is:
0.2*2*pi/(plasma freq)
When I calculate this for the electron density of the plume, the time step seems too small (around 4.2e-10s) which makes it nearly impossible to compute.
Do you have an idea what to do in this kind of condition? How should I set the time step ?
Thank you,
Best Regards,
M.Y.Balta