Plasma Parameter Scaling at High Powers for a Magnetically Shielded Hall Thruster Operating on Krypton

Hall thrusters are a mature electric propulsion technology with the potential to scale to the 100-kW range, which may enable crewed deep space travel. Magnetic shielding, a magnetic field topology that reduces thruster erosion, has extended the lifetimes of these devices, but the internal plasma properties of the thrusters differ from the traditional "unshielded" configuration. Additionally, while the traditional propellant of choice is xenon for its high mass and low ionization energy, the price of xenon has increased rapidly in recent years. Krypton is one possible alternate propellant, but its performance--particularly on shielded thrusters--is poor compared to xenon. There is therefore an apparent need to understand the performance of magnetically shielded Hall thrusters operating on krypton and how they scale to higher powers. This poster will present results from a multifluid simulation of a Hall thruster that have been calibrated with performance metrics such as thrust, discharge current, and ion velocity profiles. These simulations are then used to determine how various internal plasma parameters scale with both increasing current and voltage. The results are discussed in context of how they may impact thruster efficiencies at various operating conditions.