An Alfvenic reconnecting plasmoid thruster

Abstract

A new concept for the generation of thrust for space propulsion is introduced. Energetic thrust is generated in the form of plasmoids (confined plasma in closed magnetic loops) when magnetic helicity (linked magnetic field lines) is injected into an annular channel. Using a novel configuration of static electric and magnetic fields, the concept utilizes a current-sheet instability to spontaneously and continuously create plasmoids via magnetic reconnection. The generated low-temperature plasma is simulated in a global annular geometry using the extended magnetohydrodynamic model. Because the system-size plasmoid is an Alfvenic outflow from the reconnection site, its thrust is proportional to the square of the magnetic field strength and does not ideally depend on the mass of the ion species of the plasma. Exhaust velocities in the range of 20 to $500\ \textrm {km}\ \textrm {s}^{-1}$ , controllable by the coil currents, are observed in the simulations.

Test particle acceleration in resistive torsional fan magnetic reconnection using laboratory plasma parameters

“…When considering the competing architectures of magnetic reconnection propulsion (Cazzola et al 2016;Chesny et al 2017;Bathgate et al 2018;Ebrahimi 2020), it is anticipated that 3-D torsional reconnection may provide a pathway to more efficient plasma propulsion in comparison with the 2-D model, along with offering high specific impulse capabilities (2.03 keV ≈312 km s −1 ). Additionally, since acceleration and peak kinetic energies in torsional fan reconnection occur while particles are travelling along open magnetic field lines (figures 7 and 9) with dominant parallel momenta (figure 8), reconnection may significantly reduce or even eliminate the requirements of a magnetic nozzle to transfer particle momentum and produce thrust (Arefiev & Breizman 2004;Olsen et al 2015).…”

“…In addition to advancements in basic plasma science, laboratory investigations of torsional reconnection resulting in plasma jets may have significant implications for technology fields such as spacecraft propulsion (Chesny 2013;Cazzola et al 2016;Chesny et al 2017;Bathgate et al 2018;Cazzola, Curreli & Lapenta 2018;Ebrahimi 2020). This novel concept of exploiting magnetic reconnection for in-space propulsion faces competing architectures.…”

“…However, its efficiency was low (<1 %) and would require the addition of a magnetic mirror at one end to reflect the bidirectional flow and produce a net thrust. The recent application of the 2-D model via azimuthally symmetric plasmoid reconnection was simulated by Ebrahimi (2020). Further steps toward this operational thruster will require considerations of the pulsed nature of the reconnection process and how the plasmoid instability can operate at high frequencies.…”

Dose Limits and Countermeasures for Mitigating Radiation Risk in Moon and Mars Exploration

“…They are already used for satellite maneuvers in space, but they are less powerful than chemical thrusters. However, it is theoretically possible to produce plasma thrusters with an exhaust velocity 10× the current ones, exploiting a toroidal magnetic field similar to those used at tokamak for nuclear fusion [68]. The exhaust velocity of plasmoids can be increased or decreased by changing the strength of the magnetic fields rather than a conventional electric field increase that only produces low specific impulses.…”