The debye length is very small in the LEO environment, and in the case of simulating a large size spacecraft, the number of cells will be very large (because the grid size is usually smaller than the debye length), and it is very difficult to compute using PICVolDistrib. Is there any way to solve this problem?
Maybe make your mesh rough enough to not resolve Debye length, but to become computationally cheaper?
I’m actually wondering how relevant are those PIC simulations of ions when the mesh has a low ratio of Debye length to the cell size. Hydrodynamic simulations of electrons seem to be fine with not resolving Debye length, but for me the main concern is PIC ions on a rough, compared to Debye length, mesh.
Nevertheless, I saw many papers [exampe] where these systems are simulated using SPIS, and authors of those publications explicitly say that they’re trying to achieve a small ratio of Debye length to the cell size as they’re using quasineutrality assumption.
More than that, there are three lectures by Anatoly Spitkovsky on PIC codes on YouTube. In the second lecture he mentions his own work on pulsar jet interaction where (if I got it right) he uses a rough mesh compared to skin depth and says that it’s possible to simulate this system in this way if the size of the system is larger than 50 skin depths. He’s also citing chapter Remarks on Large Scale Plasma Simulation from Birdsail’s and Langdon’s book on PIC codes called Plasma Physics via Computer Simulation.
Perhaps the same approach is valid for those electrostatic simulations with a rough, compared to Debye length, mesh, and where you’re assuming plasma quasineutrality?
I’d be extremely grateful if someone could share their thoughts on this matter too.
Sincerely,
Egor