Sputtering distribution of LIPS200 ion thruster plume

摘要

This paper investigates the sputtering distribution of LIPS200 ion thruster plume. Considering the ground test results cannot fully represent the on-orbit status, computer simulation is highly needed to study the sputtering distribution on orbit. To ensure the credibility of simulation results, the experimental and simulation analysis in the ground test conditions were performed. After verification of the experimental results, we carried out the simulation analysis in on-orbit condition (vacuum condition). The results show that, within the off-axis angle of 70 degrees (deg), the sputtering distribution in the ground test condition is basically the same as that in vacuum condition, and the main particles causing sputtering are Xe+ and Xe2+. In the region of the off-axis angle greater than 70 deg, the sputtering result in vacuum condition is obviously lower than that in the ground test condition, and the sputtering effect is mainly caused by the charge-exchange (CEX) ions. The CEX ions in the ground test condition and vacuum condition show the "jet like" and the "mushroom like" distributions respectively. This work verifies the feasibility of the hybrid Particle-in-Cell and Direct Simulation Monte Carlo (PIC- DSMC) simulation method as well as the sputtering model to predict the space sputtering effect which can be introduced as a reference for the design of electric propulsion spacecraft.