First Results of Work with a Lithium Injector with External Lithium Supply in Plasma Discharges of the T-11M Tokamak

Abstract

Using liquid lithium to protect the first wall of tokamaks is a common idea implemented in many installations. In 2022, a lithium droplet injector (AO NIKIE) was developed to conduct real-time lithization during the discharge of T-11M tokamak, achieving excellent results. One of the drawbacks of this injector was the limited amount of lithium in the feed tank, which required its removal from the vacuum chamber of the tokamak and its depressurization for refueling. In 2024, a lithium injector with an external lithium refueling system without depressurizing the tokamak was developed. This paper presents the results of testing such an injector in the plasma discharges of the T-11M tokamak. Its performance was demonstrated experimentally; ten refuelings were performed without depressurizing the vacuum chamber of the tokamak. The main operating parameters of the injector were determined: the lithium microdroplet velocity ranged from 1.5 to 7 m/s, and the injected lithium flow varied from 10 to 70 mg/s. The effect of lithium droplet injection on the discharge parameters was studied. Calculations (modeling) of the distribution of ionized and neutral components of lithium in the plasma column were carried out.