Ten-Ampere-Level, Applied-Field-Dominant Operation in Magnetoplasmadynamic Thrusters

In this paper, applied-field magnetoplasmadynamic thrusters were operated with a discharge current lower than 20 A and an argon propellant flow rate under by using a thermionic electron emission-type hollow cathode. Both axisymmetric and rectangular channel configurations were examined. The characteristic value of the ratio of the applied-field electromagnetic thrust to the self-field electromagnetic thrust, which was a maximum of approximately 50 in previous research, increased to more than 800 in this study, whereas the specific power was in approximately the same range as in previous studies. The trends of thrust and discharge voltage were explained by referring to the “swirl acceleration” model. Such operation could be useful for near-future high-power electric propulsion applications.