• Magnetic Shielding
• Plasma-Wall Interaction
• Analytical Modeling
• Hall Thrusters

In order to get a better insight in the plasma behaviour inside a Hall effect thruster (HET), many aspects of the physics that regulates the thruster operation were investigated.An overview of current plasma-wall interaction and erosion models is presented, highlighting their advantages and drawbacks, and an original sheath model that allows for a general inclination of the magnetic field with respect to the wall is described.Then a one-dimensional model of the plasma dynamics in the acceleration channel and near plume region of a HET is formulated. The model allows for a first order study of the plasma behavior in standard configuration HETs with ideal, quasi-radial magnetic field topologies. An accurate description of plasma-wall interactions, neutral motion, electron diffusion and external plume expansion was included in the model. Moreover a sensitivity analysis of the system was performed, underlining the small influence of the pressure and of the ion's velocity boundary condition at the anode.The performance predicted by the 1D model is then compared with the experimental data available for the Alta HT-5k Thruster. After calibration, the model was capable of accurately predict the operation conditions of the thruster, thus validating the model for the analysis and design of standard HETs.In addition, non-standard, low erosion HET configurations are investigated, focusing on the magnetic shielding concept.Finally a second model of a general HET with complex 2D magnetic field topologies is formulated. Due to the anisotropy induced in the plasma by the magnetic field this second model relies on a one-dimensional approach in magnetic coordinates, assuming that the dominant plasma gradients are in the direction orthogonal to the magnetic field lines. This model is able to describe the behaviour of non-standard, possibly magnetically shielded, configurations, and will provide a design tool for the development of future, low erosion Hall effect thrusters.