Axial Magnetic Field Effect on Vacuum Arc Thruster Performance

TL;DR

This study investigates how an external axial magnetic field influences vacuum arc thruster performance, demonstrating optimal thrust and efficiency improvements through magnetic field-induced ion beam focusing and erosion rate enhancement.

Contribution

It provides experimental evidence of performance enhancement in vacuum arc thrusters due to axial magnetic fields, including optimal magnetic induction levels and associated thrust and efficiency gains.

Findings

Peak thrust of 21 μN at 2.7 W arc power

Optimal magnetic induction of 0.1 - 0.2 T

Thruster efficiency of approximately 4%

Abstract

The performance gain of co-axial vacuum arc thruster in external axial magnetic field is analyzed by power and direct thrust measurements. Thruster geometry is actively controlled and inspected using laser profilometry. Peak performance is shown to be obtained in magnetic induction of 0.1 - 0.2 T, with measured thrust of 21 uN at arc power of 2.7 W, and thruster efficiency of ~ 4 %. The performance gain is attributed to ion beam focusing, increased erosion rate, and ion acceleration due to the axial magnetic field.