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Abstract: Initial plasma-current formation via unconventional methods is a necessity in compact fusion concepts such as spherical tokamaks (STs), one of the leading designs for a fusion reactor with high magnetic field. Macroscopic fast magnetic reconnection has been shown to be instrumental during start-up current formation via magnetic helicity injection, a primary start-up current formation in STs. Inspired by this research on using magnetic-helicity injection to create start-up fusion current, state-of-the-art large-scale extended MHD computer simulations have been used to demonstrate that a particular configuration of externally applied static electric and magnetic fields can both create plasma and accelerate it by continuously producing plasmoids, plasma objects enclosed by magnetic fields that are detached from the externally applied fields. The detached plasmoids will exit spontaneously an annular thruster channel, carrying momentum that generates the thrust to propel a spacecraft. The simulations were the first to demonstrate continuous generation of plasmoids due to spontaneous fast magnetic reconnection. [F. Ebrahimi "Alfvenic reconnecting plasmoid thruster", Journal of Plasma Physics 86, Issue 6, (2020) Featured and most read article ever]. The plasmoids travel at the Alfven velocity, which depends on the strength of the magnetic field. The exhaust velocity can therefore be controlled and optimized simply by adjusting the magnetic-field strength. Exhaust velocities ranging from 20 to 500 km/s have been demonstrated in simulations. Another unique feature is that this plasma rocket does not require particular and rare gases as propellant, opening up the possibility of refueling using gases extracted from asteroids. Ongoing research both for the fusion current-drive as well as for plasma propulsion using fast magnetic reconnection will be presented.

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Meeting ID: 927 5142 0885
Passcode: Plasma