Effects of electron-drift instability in 1D fluid simulations of Hall Effect Thrusters*

A key problem of Hall Effect Thruster(HET) is the understanding of the anomalous electron transport. Recent studies have suggested as a possible cause the electron-drift instability (EDI), driven by the relative motion of electrons respects to the ions in the $\mathbf{E}\times\mathbf{B}$ direction of the thruster. Although the recent success in describing the instability and its consequences on the electron transport, few attempts have been performed to include such effects in a fluid simulation of HET, in which the anomalous transport is still artificially enhanced in order to fit experimental results. We propose in this work a comparison between the macroscopic effects induced by the EDI and the corresponding ones obtained by the ad-hoc transport. The HET is modeled through a 1D fluid simulation reproducing the axial direction of the thruster. An expression for the instability-induced friction force and power loss can be obtained from quasi-linear theory, providing the corrections to the transport equations induced by the instability. The results show a good agreement between the transport induced by the instability and that obtained from the artificial mobility, further suggesting that the relevance of the EDI in causing the anomalous electron transport.