I need to include outward emitting plasma in my simulation, and since I don’t need to simulate the thrusters, I’m using the deprecated source property to do the simulation. In the simulation my ion current and electron current are both set to 2A. however in the simulation the spacecraft surface potential is charged to an abnormal negative voltage as shown in the figure. I calculated the net emission current for all nodes using the output current data and found that the net emission current stabilized at -1.2A, which means that the surface voltage should slowly decrease from a high negative voltage. However, the voltage data only has a section where the voltage is reduced from high negative voltage, followed by an instantaneous rise in negative voltage immediately after a certain level of reduction, followed by a continued slow reduction. I think the current data is correct to some extent, but the voltage shows an abnormal trend, which should be a problem in solving the circuit. I’m wondering if it is because the current I have set is too high causing the circuit solver to show unphysical results when solving. Also the user manual of SPIS-EP mentions that SPIS-EP has reconstructed the Poisson and circuit solver for electric propulsion simulations. But I didn’t use Thruster for my simulation and also I used higher currents which might be the reason for the problem with the circuit solver.
I would like to know what I should do to avoid this? Or I can only use the thruster parameters to simulate the high current case?
