Liquid lithium surface control and its effect on plasma performance in the HT-7 tokamak

Autor: Leonid E. Zakharov, David N. Ruzic, J. Ren, Guizhong Zuo, Jiansheng Hu, J.G. Li, Z. Sun, Qingxi Yang
Rok vydání: 2014
Předmět:
Zdroj: Fusion Engineering and Design. 89:2845-2852
ISSN: 0920-3796
DOI: 10.1016/j.fusengdes.2014.05.020
Popis: Experiments with liquid lithium limiters (LLLs) have been successfully performed in HT-7 since 2009 and the effects of different limiter surface structures on the ejection of Li droplets have been studied and compared. The experiments have demonstrated that strong interaction between the plasma and the liquid surface can cause intense Li efflux in the form of ejected Li droplets – which can, in turn, lead to plasma disruptions. The details of the LLL plasma-facing surface were observed to be extremely important in determining performance. Five different LLLs were evaluated in this work: two types of static free-surface limiters and three types of flowing liquid Li (FLLL) structures. It has been demonstrated that a FLLL with a slowly flowing thin liquid Li film on vertical flow plate which was pre-treated with evaporated Li was much less susceptible to Li droplet ejection than any of the other structures tested in this work. It was further observed that the plasmas run against this type of limiter were reproducibly well-behaved. These results provide technical references for the design of FLLLs in future tokamaks so as to avoid strong Li ejection and to decrease disruptive plasmas.
Databáze: OpenAIRE