Effect of Cathode Position on Hall-Effect Thruster Performance and Near-Field Plume Properties

Sommerville, Jason D.; King, Lyon B.

doi:10.2514/6.2008-4996

Cited by 2 publications

(2 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The magnetic-circuit configuration of the T-140 HET (two concentric coils centered on the thruster centerline) restricts the position of the magnetic-field separatrix to the thruster centerline, and precludes the T-140 HET from exhibiting the off-centerline separatrix surfaces shown in HETs with magnetic coils placed off thruster centerline [34][35][36]. This magnetic-field topology eliminates any concerns about the changing nature of the near-field plume properties and cathode coupling as a function of cathode position relative to the absent off-centerline separatrix surface [34][35][36].…”

Section: B T-140 Het and Epl 500 Cathodementioning

confidence: 99%

“…Even so, it is unclear as to whether these corresponding changes are due to the increased coupling to the radial plate, due to changes caused by the cathode position relative to the HET magnetic field, or due to both of these aforementioned processes. Much work has been done on cathode position [34][35][36][42][43][44], and the general consensus is that the cathode position can be very important in determining the operating behavior of the HET. The actual physical mechanisms that drive this behavior are not fully understood.…”

Section: Het Discharge-current Oscillationmentioning

confidence: 99%

See 1 more Smart Citation

Electrical Facility Effects on Hall-Effect-Thruster Cathode Coupling: Discharge Oscillations and Facility Coupling

Walker¹,

Frieman²,

Walker³

et al. 2016

Journal of Propulsion and Power

View full text Add to dashboard Cite

The physical mechanisms that govern the electrical interaction between the Hall-effect-thruster electrical circuit and the conductive vacuum-facility walls are not fully understood. As a representative test bed, an Aerojet Rocketdyne T-140 Hall-effect thruster is operated at 3.05 kW and a xenon mass flow rate of 11.6 mg∕s with a vacuum facility operating neutral pressure of 7.3 × 10 −6 torr, corrected for xenon. Two electrical witness plates, representative of the facility chamber walls, are placed 2.3 m radially outward from thruster centerline and 4.3 m axially downstream from the thruster exit plane. The cathode is radially translated from 18.1 to 77.8 cm away from the thruster centerline. At each cathode position, the discharge current and the electrical waveform of the radial and axial plates are simultaneously measured. As the cathode radial position changes from 18.1 to 77.8 cm from the thruster centerline, the discharge-current oscillation frequency decreases between 17 and 35% for the electrically grounded thruster-body case, and between 15 and 23% for the electrically floating thruster-body case. The analysis of the electron current collected by the radial plate suggests that electrons directly sourced from the cathode impinge on the radial plate at large cathode positions. Overall, the results of this work show that the chamber walls act as an artificial electrical boundary condition that keeps the Hall-effect-thruster plume plasma potential to within certain bounds.

show abstract