Model study of the influence of the magnetic field configuration on the performance and lifetime of a Hall thruster

Abstract

A two-dimensional hybrid model of the discharge in Hall thrusters including the near outside region between cathode and exhaust plane has been developed. The topology of the applied magnetic field is calculated with a finite element software and used as input for the discharge code. In this paper, we examine the influence of the magnetic field topology on the thruster operation and properties, with emphasis on the thruster lifetime. Results show that a configuration with a zero magnetic field and a smaller region with large magnetic field tends to decrease wall erosion and low frequency current oscillations keeping a high level of performance.

A Comprehensive Cold Gas Performance Study of the Pocket Rocket Radiofrequency Electrothermal Microthruster

“…The thrust from cold gas or electrothermal thrusters is derived from the momentum of the exhausted neutral gas propellant, as distinct from electrostatic or electromagnetic thrusters, where the thrust is defined as the force in reaction to the acceleration of ions through an electric field [71,72]. PR belongs to the former class of neutral gas thrusters; it operates as an electrothermal microthruster when RF power is supplied to ionize and heat the neutral gas propellant [30,31], and as a cold gas microthruster when no RF power is supplied.…”

Operation of a segmented Hall thruster with low-sputtering carbon-velvet electrodes

“…3 A relatively long (~ 2 cm) ion acceleration region with a large voltage drop is usually located both inside the channel and outside the channel exit, where the fringing magnetic field can lead to defocusing of the ion beam. 3,4 The use of segmented electrodes along the thruster channel can provide additional control of the plasma flow in a Hall thruster. [5][6][7][8] The plume narrowing effect measured for molybdenum and carbon electrodes at low discharge voltages (≤300 V) 6,7 was attributed to the reduced voltage drop outside the channel exit.…”

Efficiency Analysis of a High-Specific Impulse Hall Thruster

“…While this may prove to be accurate, there are still questions concerning the rate at which lifetime decreases with voltage. Modeling by Garrigues, et al [52] has begun to address some of these issues by demonstrating how erosion rates in 1600 s specific impulse thrusters decrease when a plasma lens is used (in lieu of less concave magnetic field lines). Efforts to predict the operational lifetime of NASA Hall thrusters are also currently be pursued [53].…”