Dynamic Electric Field Calculations Using a Fully Kinetic Ion Thruster Discharge Chamber Model

Abstract

In this work, we present a fully kinetic particle-in-cell - Monte Carlo Collision (PIC-MCC) computer model developed to calculate the dynamic electric field inside an ion engine discharge chamber. This model self- consistently tracks primary electrons, secondary electrons, singly charged and doubly charged xenon ions, and xenon neutrals inside the discharge chamber. Both electric and magnetic field effects are included in the particle tracking. The plasma potential results are evaluated at every time step based on the charged particle distribution. This model avoids using an artificial inflated permittivity assumption and also avoids the use of the experimentally measured plasma potential data in the electric field calculations. Instead, a self-similar scaling system is considered. The computer model has been applied to study NASA's Next Generation Xenon Thruster (NEXT) operating at 5.3 kW, 3.1 A beam current, and 1567 V beam voltage. We discuss the recent algorithm development and present preliminary results such as the electric potential maps, the particle number density distributions, and the particle energy distributions from the NEXT ion thruster discharge chamber simulations.