Message by **Torbjorn Sundberg**:

Hello SPINE!

I’ve been doing some test runs with the new SPIS version (3.6). I like the software but I’ve run into some problems that I need some help sorting out:

My initial tests have been to simulate a langmuir probe and to compare the SPIS value of I and V to my analytical values.

For some reason, I haven’t been able to make the voltage level converge - it just drop linearly. By doing some attempts with varied initial potential, It seems to me that the convergence potential lies somewhere between -500 and -1000 V (which just doesn’t seem reasonable!)

I have tried varying the following to see if they would make any difference, but so far without any success:

- mesh size
- size of the plasma sphere
- particles per cell

Group settings: spacecraft

- ITO shade
- spacecraft default plasma

You can find more comments, the geometry file and a sample run at: \http://www.staff.alfvenlab.kth.se/torbjorn.sundberg/spis \http://www.staff.alfvenlab.kth.se/torbjorn.sundberg/spis/2sphere2 So.. Does anyone have any idea on how to interpret this, or is there perhaps some crucial parameter that I might have missed or misused?

Kind regards,

Torbjörn