Abstract:The Kaufman ion thruster is one of the types of electric propulsion used in spacecraft due to its high specific impulse, high efficiency, and long life. In the past, the research mainly focuses on the Kaufman ion thruster with axisymmetric cylindrical structure. However, for the future modular cube satellite, the cube configuration thruster is well suited for the combination of multiple thrusters, the collective neutralization of the plume of multiple thrusters, the compact structure and the reduction of spacecraft accessories. Based on the self-designed cubic Kaufman ion thruster, the three-dimensional numerical simulation method is used to calculate and analyze the thruster discharge chamber, and the magnetic field distribution of the thruster discharge chamber under different cathode pole shoe inner diameters is obtained. The electron density distribution and electron temperature distribution in the discharge chamber under different pole shoe configurations are comparatively studied. The results show that increasing the inner diameter of the cathode shoe makes the distribution uniformity of the magnetic field worse, the electron temperature on the inner wall of the discharge chamber increases, the electron loss increases, and the ion density at the outlet of the discharge chamber decreases. Therefore, for this cubic Kaufman ion thruster, the cathode pole shoe with a length, width and height of 15mm×12.5mm×15mm is the best configuration, which can not only maintain a lower electron temperature on the wall, but also facilitate the ion uniformity at the thruster outlet.