This project will develop advanced inner wall materials incorporating flowing liquid plasma-facing surfaces to withstand the high levels of surface heat flux generated from fusion energy systems Attractive fusion energy sources will require the use of new concepts and advanced materials able to withstand the high levels of surface heat flux and neutron wall loads for in-vessel components. The application of free surface flowing liquids as plasma-facing components in future fusion energy systems will meet this need. This project will examine key liquid-plasma interaction issues to assess the feasibility of free surface flowing liquids as advanced plasma-facing components for future fusion systems. These issues include effective hydrogen/helium particle retention, liquid erosion (sputtering, evaporation), power extraction, vapor shielding, and macroscopic liquid removal. Phase I, focusing on liquid lithium, evaluated the technical feasibility of developing and fabricating free surface flowing liquid modules that could be implemented in future fusion energy systems. Both hydrogen/helium particle retention and plasma-liquid interaction issues (sputtering, evaporation) were evaluated under low flux conditions. Phase II will measure the magneto-hydrodynamic effect on particle retention/pumping of free surface flowing liquids under fusion-relevant conditions. In addition, plasma-liquid interactions will be measured and modeled under high heat flux conditions to assess vapor shielding mechanisms, particle entrainment, and liquid erosion. Commercial Applications and Other Benefits as described by awardee: The development and fabrication of free surface flowing liquid modules for future fusion energy systems should meet both short and long-term performance criteria for existing and future energy systems
