The performance of a magnetic nozzle enhanced magnetoplasmadynamic thruster.

A magnetic nozzle enhanced magnetoplasmadynamic thruster (ME-MPDT) is proposed as a modification of the conventional applied field magnetoplasmadynamic thruster (AF-MPDT). In contrast to AF-MPDTs, ME-MPDT features a reduced discharge chamber, shifting the energy injection zone from the discharge chamber to the magnetic nozzle. The majority of argon is injected directly into the magnetic nozzle via the cathode, where it undergoes ionization and acceleration. Thrust, specific impulse, total efficiency, and thrust-to-power ratio of ME-MPDT are assessed using an elastic thrust stand. Comparing ME-MPDT to the standard AF-MPDT at a discharge current of 250 A and a magnetic field of 0.15 T, it demonstrates a 20% increase in thrust and a 15% increase in discharge voltage. To understand the reason behind this performance enhancement, both thrusters are simulated using a two-temperature MHD model. The simulation model is solved by the ANSYS FLUENT. The performance boost is attributed to an increase in azimuthal diamagnetic current within the magnetic nozzle, with ME-MPDT exhibiting 25% higher azimuthal diamagnetic current compared to AF-MPDT. Under these experimental conditions, ME-MPDT achieves its best performance at a discharge current of 250 A, power input of 22 kW, and a magnetic field of 0.15 T, resulting in a thrust of 485 mN, a specific impulse of 2356 s, and a thrust efficiency of 28%. • A new structure of applied field magnetoplasmadynamic thruster is proposed. • The energy injection area is changed to the magnetic nozzle. • The performance can be improved by increasing the energy in the magnetic nozzle. • The performance boost in ME-MPDT is from higher diamagnetic current in the magnetic nozzle. [ABSTRACT FROM AUTHOR]