Near-field angular distributions of high velocity ions for low-power hall thrusters

Abstract

Abstract-Experimental angular distributions of highenergy primary ions in the near-field region of a small Hall thruster between 50-200 mm downstream of the thruster exit plane at a range of centerline angles have been determined using a highly-collimated, energy-selective diagnostic probe. The measurements reveal a wide angular distribution of ions exiting the thruster channel and the formation of a strong, axially-directed jet of ions along the thruster centerline. Comparisons are made to other experimental determinations as applicable.

Effect of Wall Sheaths on Ion Trajectories in a Hall Thruster Numerical Model

“…This is substantially less than the angle change required to produce the high velocity, high angle population seen in experiments. To reproduce the experimental results, one would have to see a change in angle of 60 to 80º [1], [2]. This suggests that another mechanism may be responsible for producing high velocity, high angle ions.…”

“…Recent experimental studies have revealed the presence of high velocity ions at high angles off the centerline in Hall thruster plumes [1], [2]. These ions have kinetic energies that are higher than can be explained by collisional processes such as charge exchange and elastic scattering, and are thought to be ions that have been accelerated through nearly the full acceleration potential of the thruster [3].…”

Optimization of magnetic field design for Hall thrusters based on a genetic algorithm

“…The optimal plume divergence angle is determined to be 41.27°, consistent with the experimentally determined angle for the designated magnetic field configuration. Through an extensive survey of literature concerning the SPT-70, the typical range of optimal plume divergence angles is revealed as 44.7°-57.4° [50][51][52][53][54][55]. Specifically, Qian et al mentioned The reproducibility of the genetic algorithm is tested by varying the crossover and mutation rates.…”