Progress on Hall2De Simulations with First-Principles Model of the Anomalous Momentum-Transfer Collision Frequency

We report on the first set of numerical simulations that make use of a recently developed first principles, closed-form model of the anomalous momentum-transfer collision frequency in a Hall thruster discharge. First, the model is implemented only in the interior of the channel, upstream of the acceleration region, while in the downstream portion an empirically derived model is still applied. We find that these simulations agree well with experimental measurements and can reproduce the dynamic behavior of the plasma. We then report on our first attempts to implement the model everywhere in the computational domain. We were able to achieve a stable simulation in the SPT-140 in which the steady state solution reproduced quite well the measured ion velocity. These first numerical experiments have also confirmed some expected challenges, however, mainly associated with the ab initio prediction of the location of the maximum out-of-plane drift velocity inside the channel. We outline possible avenues for overcoming this challenge, such as augmenting the model with the anomalous electron heating that also occurs in the presence of plasma instabilities.