2024 – Investigate performance of 3D printed capillary porous structures carrying liquid lithium under H-mode plasma exposure

Investigate performance of 3D printed capillary porous structures carrying liquid lithium under H-mode plasma exposure

2024 Research Campaign, Thrust: FPP Candidate Wall Materials

Purpose of Experiment

This experiment aims to explore the behavior of lithium within a 3D printed tungsten (W) capillary porous structure (CPS) when exposed to H-mode deuterium plasmas in the DIII-D tokamak. The primary objectives are to study lithium transport and redeposition, evaluate the CPS’s ability to prevent droplet formation and leakage and examine the effect of fuel puffing on lithium evaporation and transport. Additionally, the experiment will assess fuel retention in the target and in lithium-deuterium co-deposits near the target. This research contributes to the development of liquid metal divertor designs, which offer advantages such as self-replenishment and enhanced heat handling capabilities, essential for future fusion power plants.

Experimental Approach

The experiment involves mounting a lithium-filled CPS on the DiMES platform in the DIII-D tokamak. The CPS will be pre-heated above lithium’s melting point to ensure proper plasma interaction. The experiment will consist of a series of shots in both low and high-power H-mode configurations, with varying initial CPS temperatures. Diagnostic tools, including spectroscopy, ion beam analysis, and scanning electron microscopy, will be used to measure lithium transport, redeposition, and fuel retention. Visual inspections using infrared and fast cameras will monitor droplet formation. The experiment will also incorporate deuterium puffing to study its impact on lithium evaporation and transport. Data from these experiments will help optimize CPS designs and improve the understanding of liquid lithium behavior in a fusion environment.