Global modeling of iodine Hall thruster performance and discharge properties

Abstract

A 0D model for an iodine-fed Hall thruster is presented. A complete set of reactions is used to account for iodine plasma chemistry phenomena and trace the presence of multiple neutrals and ionized species. The model is developed using novel assumptions based on experimental data trends as derived from the literature. The simulation domain is divided into two zones in order to refine the iodine molecule dissociation process localized in the low electron temperature region found upstream in the channel. After validating a xenon version of the model against SPT-100 characteristics, numerical results are compared against experimental data relative to a low-power iodine-fed Hall thruster. Discharge current and thrust are predicted with satisfactory quantitative agreement, and overall trends are effectively captured. The numerical results indicate a relatively large portion of ionized molecules, while negative ions appear to occur in non-negligible amount upstream in the thruster channel.