Anomalous electron mobility modeling in Hall thrusters

Abstract

Accurate modeling of the anomalous electron mobility is crucial for successful simulation of Hall thrusters. Existing computational models for the anomalous electron mobility are used to simulate the UM/AFRL P5 Hall thruster in a 2D axisymmetric hybrid PIC-MCC code. Comparison to experimental results indicates that while these computational models can be tuned to reproduce the correct thrust or discharge current, it is very difficult to match all integrated performance parameters (thrust, power, discharge current, etc.) simultaneously. Furthermore, multiple configurations of these computational models can produce reasonable integrated performance parameters. Mean centerline potential profiles from these simulations are presented to provide physical insight into the relationship between the electron mobility and the spatial variation of the plasma potential.

Study on Anomalous Electron Diffusion in the Hall Effect Thruster

“…Thus, it can be seen that higher electron anomalous diffusion is required for the thruster to sustain discharge in the case of lower anode mass flow rate operation, which, in turn, indicates that if the anomalous electron diffusion is insufficient, , because the anomalous diffusion should be approximately doubled from the experimental results [5,18], 50 and 80 are taken as the lower and upper bounds, respectively. The selected ranges of the anomalous coefficients will be fixed in this paper and the investigation of varying the ranges is left for future work.…”

“…[5] and [18], the effects of the Bohm-type diffusion should change from inside the discharge channel to outside the discharge channel. In particular, the diffusion is approximately doubled outside the channel versus inside the channel.…”

One Dimensional Hybrid-Vlasov Simulation of a Hall Thruster

“…Analysis of the electron fluid model is not presented since the effects of the models and parameters of electron mobility and other collision frequencies are shown in several papers. 10,11 …”

Modeling of Electron Fluids in Hall Thrusters Using a Hyperbolic System

“…(4) is based on the classical diffusion model, and this model is subject to change for better reflection of magnetic confinements such as the Bohm diffusion model, depending on the situation. 9 The electron mobility on a computational mesh of axial-radial coordinate system is derived by rotating [µ] mag with the angle between the magnetic lines of force and the computational mesh.…”