Speaker
Laetitia Frances
(ITEP)
Description
Tritium self-sufficiency and management in nuclear fusion power plants is still challenging. Advanced technologies to extract tritium from lead lithium (Pb-16Li) as possible breeder material are required. The Vacuum Sieve Tray (VST) method consists in pushing Pb-16Li through a tray of submillimeter scaled nozzles towards a chamber maintained under dynamic vacuum. At the exit of each nozzle, an instable liquid jet is formed which breaks up in droplets, whose oscillations (up to 200 Hz) are presumed to enhance the hydrogens mass transport to their surface. The VST has experimentally proved to be efficient to extract deuterium, used to mimic tritium but avoiding the constraint of radioactivity [1].
We first developed a model to calculate the extraction efficiency, describing in details the pressure losses along the Pb-16Li flow. It was applied to design a single-nozzle VST experiment operable with tritium. A multi-nozzle VST experiment with deuterium was also developed to mitigate the risks and to tackle technical issues (Pb-16Li solidification, corrosion rates, Sieverts’ constant…). Moreover, this experiment also extends the possibilities of the single-nozzle concept, as it includes multi-nozzle trays, where deuterium extracted from one droplet may be reabsorbed by another one limiting the extraction efficiency.
This contribution presents the complementary goals and expectations of the single-nozzle and multi-nozzle experiments to be performed respectively with T2 and D2. Experiments intended to validate and adjust the models used to calculate extraction efficiency and to quantify multi-nozzle disturbances are proposed and discussed. The confrontation of the theoretical approach and experimental results will allow understanding the impact of the geometry (nozzle, tray and set-up) on the extraction efficiency depending on the mass flow rate.
[1] F. Okino, K. Noborio, R. Kasada, S. Konishi, Fusion Sci. Technol., 64 (3), 543–548, 2013.
Co-authors
Alejandro Munoz
(ITEP, Karlsruhe Institute für Technology, Eggenstein-Leopoldshafen, Germany)
David Demange
(ITEP, Karlsruhe Institute für Technology, Eggenstein-Leopoldshafen, Germany)
Ester Diaz
(Gent University, St. Pietersnieuwstraat 33, 9000 Gent, Belgium)
Laetitia Frances
(ITEP, Karlsruhe Institute für Technology, Eggenstein-Leopoldshafen, Germany)
Merlijn Mertens
(Gent University, St. Pietersnieuwstraat 33, 9000 Gent, Belgium)
