Dynamics of scrape-off layer filaments in high β plasmas

(published 2019)

Plasma Filament animation

Tokomaks are large, doughnut shaped vessels which harness the power of the sun - nuclear fusion. The technology is still being developed, but by the end of the century it could provide abundant, environmentally friendly energy to power our green future. Tokomaks heat isotopes of Hydrogen gas until the electrons separate from the nuclei and a plasma is formed. A powerful magnetic field is used to contain the hot plasma, to prevent it from touching (and damaging) the walls of the tokomak.

Unfortunately, confined plasmas aren't complete stable. You may have seen images of the sun, with giant loops of plasma erupting from the surface, or large bursts being ejected. Similar physics can lead to long, thin filaments of plasma being ejected from the core of the tokomak, which can cause damage if not carefully controlled. In this study, we look at how these filaments interact with the magnetic field of the tokomak, as shown in the animation above. We find that as we move to the larger and more powerful tokomaks required to produce energy these filaments' behaviour will change and model equations need to be updated to account for this.