Demonstrating electromagnetic control of free-surface, liquid-metal flows relevant to fusion reactors

• Published in: Nuclear fusion Vol. 58; no. 1; pp. 16022 - 16033
• Main Authors: Hvasta, M.G., Kolemen, E., Fisher, A.E., Ji, H.
• Format: Journal Article
• Language: English
• Published: United States IOP Publishing 01.01.2018; IOP Science
• Subjects: 70 PLASMA PHYSICS AND FUSION TECHNOLOGY; electromagnetic control; free-surface flow; galinstan; liquid metal; plasma facing components
• ISSN: 0029-5515; 1741-4326
• DOI: 10.1088/1741-4326/aa9344

Plasma-facing components (PFC's) made from solid materials may not be able to withstand the large heat and particle fluxes that will be produced within next-generation fusion reactors. To address the shortcomings of solid PFC's, a variety of liquid-metal (LM) PFC concepts have been proposed. Many of the suggested LM-PFC designs rely on electromagnetic restraint (Lorentz force) to keep free-surface, liquid-metal flows adhered to the interior surfaces of a fusion reactor. However, there is very little, if any, experimental data demonstrating that free-surface, LM-PFC's can actually be electromagnetically controlled. Therefore, in this study, electrical currents were injected into a free-surface liquid-metal that was flowing through a uniform magnetic field. The resultant Lorentz force generated within the liquid-metal affected the velocity and depth of the flow in a controllable manner that closely matched theoretical predictions. These results show the promise of electromagnetic control for LM-PFC's and suggest that electromagnetic control could be further developed to adjust liquid-metal nozzle output, prevent splashing within a tokamak, and alter heat transfer properties for a wide-range of liquid-metal systems.