An electron transport model based on orbit theory in external discharge Hall thruster E×B field

The external discharge Hall thruster, utilizing a negative gradient magnetic field topology and completely eliminating the physical discharge channel, holds the potential to effectively address plasma-wall erosion, significantly extending the operational lifespan of the thruster. It represents a promising new type of lowpower Hall thruster. However, the overall efficiency of the external discharge Hall thruster remains relatively low, necessitating further research on enhancing working gas ionization efficiency and reducing plume divergence angles. Current investigations into the discharge mechanisms within the E×B field often commence with plasma simulation methods such as fluid simulations or PIC(Particle In Cell)-MCC((MonteCarlo collision) simulations. While these methods can elucidate experimental phenomena, they fail to provide a clear physical picture. This paper proposes a semi-dynamic, semi-statistical electron transport model based on single-particle orbital theory. The model defines a region within the ExB field where electrons undergo stable Hall drift motion. This region, serving as the probable location for ionization events, may evolve into criteria for optimizing thruster performance based on parameters such as length and size. The model also analyzes the influence patterns of factors like anode voltage and magnetic field strength on this region, validating the analysis with experimental images of the plume. This approach allows for a deeper understanding of the ionization process in external discharge Hall thrusters and provides insights for optimization. It is noteworthy that while the model is built upon the structure and parameters of external discharge Hall thrusters, it holds general applicability for traditional Hall thrusters and $E \times B$ field discharges at low pressure.

The external discharge Hall thruster, utilizing a negative gradient magnetic field topology and completely eliminating the physical discharge channel, holds the potential to effectively address plasma-wall erosion, significantly extending the operational lifespan of the thruster. It represents a promising new type of lowpower Hall thruster. However, the overall efficiency of the external discharge Hall thruster remains relatively low, necessitating further research on enhancing working gas ionization efficiency and reducing plume divergence angles. Current investigations into the discharge mechanisms within the E×B field often commence with plasma simulation methods such as fluid simulations or PIC(Particle In Cell)-MCC((MonteCarlo collision) simulations. While these methods can elucidate experimental phenomena, they fail to provide a clear physical picture. This paper proposes a semi-dynamic, semi-statistical electron transport model based on single-particle orbital theory. The model defines a region within the ExB field where electrons undergo stable Hall drift motion. This region, serving as the probable location for ionization events, may evolve into criteria for optimizing thruster performance based on parameters such as length and size. The model also analyzes the influence patterns of factors like anode voltage and magnetic field strength on this region, validating the analysis with experimental images of the plume. This approach allows for a deeper understanding of the ionization process in external discharge Hall thrusters and provides insights for optimization. It is noteworthy that while the model is built upon the structure and parameters of external discharge Hall thrusters, it holds general applicability for traditional Hall thrusters and field discharges at low pressure.