Numerical model for axisymmetric inductively coupled plasma (ICP) in radio-frequency (RF) ion thrusters

A numerical model is developed to evaluate the inductively coupled plasma properties in a 2-D axisymmetric domain inside an RF ion thruster discharge chamber. The model is built by incorporating an electromagnetic model with a fluid model to describe the plasma. The three species, ions, electrons and neutrals, inside the plasma are modeled assuming that they obey the continuum approach. The spatial distributions of flow parameters are obtained by solving the fluid equations with the SIMPLE algorithm using the finite volume discretization. The flow parameters that can be monitored are ion number density, ion velocity in three dimensions, neutral number density, neutral velocity in three dimensions, electron flux, electron temperature, electric potential and electromagnetic fi elds. The resulting flow parameters are used to evaluate the thruster performance and e fficiency. The model presented in this study demonstrates the same tendency with the experimental results from the literature and verifi ed through comparison with commercial codes. The code is implemented as a software framework, which is named as AETHER, using C++ programming language. The model lays out that after a certain amount of power deposition, there is a trade-o between the e fficiency and the thrust in an RF ion thruster.