Study on the erosion phenomenon at the bottom channel of magnetically insulated anode cylindrical Hall thruster

In this experimental study, the ceramics of a cylindrical Hall thruster with a magnetically insulated anode structure at the bottom of a discharge channel was found to be eroded. The potential, distribution of the ion number density, ion velocity in the channel, and the power density into the bottom of the channel were analyzed through a particle-in-cell numerical simulation. The results of this study indicate that the electrons move along the magnetic line to the bottom of the channel where the negative charges accumulated form a negative potential. Under a potential action, some low-energy ions in the channel move toward the bottom of the channel in an accelerating manner, causing an erosion of the ceramic material; the deposition power density reaches the peak value at the bottom center and gradually decreases in a radial direction, which is consistent with the actual erosion occurring at the bottom of the channel.