NEXT ION OPTICS SIMULATION VIA ffx

Simulations of the erosion processes for two proposed sets of ion thruster grids for the NEXT project are presented. Structural failure and electron backstreaming due to accel grid erosion are discussed as two possible failure mechanisms of these grid sets. The TAG grid set is shown to outperform the NSTAR grid set both in terms of margin against electron backstreaming and accel grid mass loss at the primary operating condition studied. An investigation into the possibility of reducing the accel grid voltage magnitude for the TAG grid set showed improved propellant throughput capability. Results of erosion simulations predicting propellant throughput capability for the TAG grid set are presented for a range of NEXT operating conditions.