Magnetohydrodynamic Analysis of High Mass Flow Rate-Induced High-Density Plasma Hall Thruster Operation.

Abstract: Hall thrusters are widely used in the field of electric propulsion due to their high efficiency and specific impulse. However, the reliance on xenon as a propellant is challenging due to its scarcity and cost, leading to interest in alternatives such as argon and krypton. A key limitation of these alternative propellants is their lower propellant utilization efficiency, which can be addressed by increasing the neutral density within the ionization region. This study investigates a high-density plasma Hall thruster design by scaling down the anode cross-sectional area of the RAIJIN66 thruster while maintaining the same mass flow rate and power. This geometric modification increases neutral density, enhancing ionization but also decreasing the Hall parameter due to higher electron-neutral collision frequencies. To compensate for this effect and sustain efficient thruster operation, the magnetic flux density must be increased by a factor of four using a permanent magnet. A magnetohydrodynamic (MHD) framework is employed to analyze electron behavior under these high-density conditions, utilizing a two-fluid model for ions and electrons. To study the thrust generation at high plasma densities, electromagnetic acceleration is analyzed, which is quantitatively equivalent to conventional electrostatic acceleration. This research shows how increased neutral density enhances performance and mitigates negative effects through magnetic field adjustments, contributing to the development of Hall thrusters optimized for alternative propellants and scalable space applications.

Recommended citation: Barth N, Suehiro T, Satpathy D, Lee J, Komurasaki K, Sekine H, Koizumi H. Magnetohydrodynamic Analysis of High Mass Flow Rate-Induced High-Density Plasma Hall Thruster Operation. Asian Joint Conference on Propulsion and Power (AJCPP).