Tapered coils system for space propulsion with enhanced thrust: a concept of plasma detachment

A concept for plasma detachment in a magnetic nozzle is developed based on the detachment region which is found to decrease with the taper angle of the coils employed in the proposed flexible three coil setup. On tapering the coils while resulting in the same cross-sectional area, the plasma plume outside the throat grows radially that leads to an enhancement in the thrust from 2.67 mN to 5 mN at the final detachment plane for a rise in the taper angle from $0$ to 13°. The maximum thrust can reach about 9 mN when the middle coil is shifted closer to the right coil along with increasing middle-to-outer-coil diameter (inner) ratio from 1 to 3. Proposed three-tapered-coils arrangement for a magnetic nozzle turns out to be a robust candidate for space propulsion offering the ability to control plasma detachment and tune thrust in-flight simply via mechanical movements without changing the current.