Critical assessment of a two-dimensional hybrid Hall thruster model: Comparisons with experiments

TLDR

It is well known that classical cross‑field electron transport and energy losses cannot explain the observed Hall effect thruster characteristics. The study discusses the predictive capabilities of a two‑dimensional hybrid Hall effect thruster model. The 2D quasineutral hybrid model employs empirical parameters to capture anomalous electron transport and energy loss, and predicts ionization and transit‑time oscillations that affect time‑averaged thruster properties. With appropriately tuned empirical parameters, the model qualitatively reproduces observed thruster behavior across many operating conditions and demonstrates how parameter choices influence measurable quantities.

Abstract

A discussion is presented on the results and predictive capabilities of a two-dimensional (2D) hybrid Hall effect thruster (HET) model. It is well known that classical (collision-induced) cross-field electron transport and energy losses are not sufficient to explain the observed HET characteristics. The 2D, quasineutral, hybrid discharge model uses empirical parameters to describe additional, anomalous electron transport and energy loss phenomena. It is shown that, for properly adjusted empirical parameters, the model can qualitatively reproduce the observed thruster behavior over a large range of operating conditions. The ionization and transit-time oscillations predicted by the model are described, and their consequences on the time-averaged thruster properties are discussed. Finally, the influence of the empirical parameters on the model results is shown, especially on quantities that can be measured experimentally.