Comparison of Numerical and Experimental Time-Resolved Near-Field Hall Thruster Plasma Properties

Breathing mode oscillations of a xenon 600 W Hall effect thruster have been studied using temporally resolved experimental data and numerical modeling. Fluctuations in xenon neutral near infrared (810-835 nm) emission in the near field thruster plume have been measured at 1- μs resolution using a high speed, phase-matched intensified charge coupled device. Oscillations in electron temperature, 3-9 eV, have been inferred using a collisional-radiative model and a two-line ratio method. The time-resolved emission and electron temperature measurements are then used to assess the accuracy of the numerical model HPHall. Although simulations were able to accurately predict the time averaged thruster behavior, the model greatly under predicts the magnitude of the oscillations. General phase trends between the discharge current and emission as well as electron temperature are consistent with observations, suggesting that the model is capable of capturing some of the oscillatory behavior despite the dampening of the oscillations.