Use of Lithium Capillary Structures in Ohmic Discharges of T-10 Tokamak

IF 0.9 4区物理与天体物理 Q4 PHYSICS, FLUIDS & PLASMAS Plasma Physics Reports Pub Date : 2024-05-16 DOI:10.1134/s1063780x2460021x

V. A. Vershkov, D. V. Sarychev, D. A. Shelukhin, A. R. Nemets, S. V. Mirnov, I. E. Lyublinski, A. V. Vertkov, M. Yu. Zharkov

{"title":"Use of Lithium Capillary Structures in Ohmic Discharges of T-10 Tokamak","authors":"V. A. Vershkov, D. V. Sarychev, D. A. Shelukhin, A. R. Nemets, S. V. Mirnov, I. E. Lyublinski, A. V. Vertkov, M. Yu. Zharkov","doi":"10.1134/s1063780x2460021x","DOIUrl":null,"url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The results of experiments at the T-10 tokamak using lithium capillary-porous structures are presented. It is shown that lithium sputtering under conditions of graphite diaphragms can significantly reduce deuterium recycling and the level of impurities in the plasma. At the same time, recycling increases significantly five discharges after the start of the day of the experiment, and the effect of reducing the level of impurities persists for 150–300 discharges. The results of using a capillary-porous structure with lithium filling as a movable rail diaphragm in the T-10 configuration with tungsten main diaphragms are presented. The introduction of a lithium diaphragm into the SOL region makes it possible to reduce recycling and obtain discharges with an effective plasma charge approaching unity. In this case, the effect increases as the lithium sputtered in the chamber is accumulated. It is shown experimentally that a capillary-porous structure with lithium filling can be used as a main diaphragm with longitudinal plasma heat fluxes up to 3.6 MW/m<sup>2</sup>. However, a necessary condition is the complete impregnation of the porous structure with lithium and the prevention of extrusion of lithium into the discharge as a result of the interaction of the current flowing to the diaphragm with the toroidal magnetic field. Experiments have shown that to obtain discharges with a small lithium admixture, a strong gas injection of deuterium or impurity is required to reduce the temperature of the plasma periphery and effective cooling of the diaphragm below 450°C. Otherwise, the diaphragm transfers into a strong evaporation mode with high lithium flows, which lead to a significant increase in the lithium concentration in the plasma. Strong evaporation reduces the heat inflow and stabilizes the diaphragm temperature.</p>","PeriodicalId":735,"journal":{"name":"Plasma Physics Reports","volume":null,"pages":null},"PeriodicalIF":0.9000,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Plasma Physics Reports","FirstCategoryId":"101","ListUrlMain":"https://doi.org/10.1134/s1063780x2460021x","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"PHYSICS, FLUIDS & PLASMAS","Score":null,"Total":0}

引用次数: 0

Abstract

The results of experiments at the T-10 tokamak using lithium capillary-porous structures are presented. It is shown that lithium sputtering under conditions of graphite diaphragms can significantly reduce deuterium recycling and the level of impurities in the plasma. At the same time, recycling increases significantly five discharges after the start of the day of the experiment, and the effect of reducing the level of impurities persists for 150–300 discharges. The results of using a capillary-porous structure with lithium filling as a movable rail diaphragm in the T-10 configuration with tungsten main diaphragms are presented. The introduction of a lithium diaphragm into the SOL region makes it possible to reduce recycling and obtain discharges with an effective plasma charge approaching unity. In this case, the effect increases as the lithium sputtered in the chamber is accumulated. It is shown experimentally that a capillary-porous structure with lithium filling can be used as a main diaphragm with longitudinal plasma heat fluxes up to 3.6 MW/m². However, a necessary condition is the complete impregnation of the porous structure with lithium and the prevention of extrusion of lithium into the discharge as a result of the interaction of the current flowing to the diaphragm with the toroidal magnetic field. Experiments have shown that to obtain discharges with a small lithium admixture, a strong gas injection of deuterium or impurity is required to reduce the temperature of the plasma periphery and effective cooling of the diaphragm below 450°C. Otherwise, the diaphragm transfers into a strong evaporation mode with high lithium flows, which lead to a significant increase in the lithium concentration in the plasma. Strong evaporation reduces the heat inflow and stabilizes the diaphragm temperature.

Abstract Image

查看原文

微信好友朋友圈 QQ好友复制链接

本刊更多论文

在 T-10 托卡马克欧姆放电中使用锂毛细管结构

摘要介绍了在 T-10 托卡马克使用锂毛细管多孔结构的实验结果。实验结果表明，在石墨隔膜条件下进行锂溅射可以显著减少氘的回收和等离子体中的杂质含量。同时，在实验日开始后的 5 次放电中，氘的回收量会明显增加，而降低杂质含量的效果会持续 150-300 次放电。报告介绍了在 T-10 配置中使用填充锂的毛细管多孔结构作为活动轨道隔膜和钨主隔膜的结果。将锂隔膜引入 SOL 区域可以减少循环，并获得有效等离子电荷接近于一的放电。在这种情况下，随着腔室中溅射的锂的积累，效果也会增加。实验表明，填充锂的毛细管多孔结构可用作主隔膜，纵向等离子体热通量可达 3.6 MW/m2。然而，一个必要条件是多孔结构完全浸渍锂，并防止流向隔膜的电流与环形磁场相互作用而将锂挤出到放电中。实验表明，要获得掺杂少量锂的放电，需要注入大量氘或杂质气体，以降低等离子体外围的温度，并将隔膜有效冷却到 450°C 以下。否则，隔膜会转入高锂流的强蒸发模式，导致等离子体中的锂浓度显著增加。强蒸发可减少热量流入并稳定隔膜温度。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文去求助

来源期刊

Plasma Physics Reports 物理-物理：流体与等离子体

CiteScore

1.90

自引率

36.40%

发文量

104

审稿时长

4-8 weeks

期刊介绍： Plasma Physics Reports is a peer reviewed journal devoted to plasma physics. The journal covers the following topics: high-temperature plasma physics related to the problem of controlled nuclear fusion based on magnetic and inertial confinement; physics of cosmic plasma, including magnetosphere plasma, sun and stellar plasma, etc.; gas discharge plasma and plasma generated by laser and particle beams. The journal also publishes papers on such related topics as plasma electronics, generation of radiation in plasma, and plasma diagnostics. As well as other original communications, the journal publishes topical reviews and conference proceedings.