Congratulations to our postdoc Bob Davies for being awarded a EUROfusion Bernard Bigot Researcher grant (ERG). Bob will be working on solving the “exhaust problem” for stellarator fusion reactors (“Novel exhaust solutions and scrape-off layer physics in optimised stellarators”).
The stellarator concept for fusion energy has come along in leaps and bounds, from the world record-breaking results of Wendelstein 7-X in Greifswald to the eye-wateringly sophisticated optimisation tools which will design the stellarators of tomorrow. But one fundamental aspect of stellarator design stands out and begs attention: how should the exhausted heat and particles be managed?
The temperatures inside a burning fusion plasma are about ten times higher than those at the centre of the Sun, and in steady-state operation heat must be constantly expelled, captured and converted into electricity. Simultaneously, Helium, the “ash” generated by the fusion reaction, must be steadily removed to avoid choking the plasma. So the challenge is to carefully design both the magnetic field on the outermost part of the plasma (i.e. near the wall of the machine) and the solid plasma-facing components; this dramatically affects the component lifetimes, and the efficacy of Helium removal. Optimising the exhaust directly affects the economic viability of a fusion power plant, so it’s an important problem!
A variety of candidates exist for a stellarator exhaust solution, including the use of magnetic islands seen in Wendelstein 7-X, the “helical divertor” seen in the Large Helical Device in Japan, and the exploitation and tailoring of magnetic chaos. Supporting and furthering these experimental efforts are sophisticated simulation tools, which can predict the performance of different solutions, and can therefore also be used as design tools. However, as of today, there is no systematic way of designing the edge magnetic field and the plasma-facing components in order to address the multiple (and sometimes competing) requirements of an exhaust solution.
This project will delve into edge magnetic field optimisation and plasma-facing component design from a theoretical and computational physics perspective. Bob will seek to better understand the physics at play in the stellarator edge and how to incorporate this knowledge into stellarator design/optimisation packages, with the ultimate aim of providing a “recipe” for exhaust optimisation. He will use this recipe to cook up solutions for several existing fusion reactor candidates, including so-called “SQuIDs”: a new class of stellarator discovered by Max Planck Institute and being actively pursued by private sector here in Germany.
Directeur de recherche CEA
3moDoes that mean ICF with lasers could be considéred at the right for funding, if " WE are all un the same boat " ? 🤔