Computer Simulation of Plasma-Surface Interactions in Fusion Devices

聚变装置中等离子体-表面相互作用的计算机模拟

• 批准号: 09680494
• 负责人: OHYA Kaoru
• 金额: $ 1.6万
• 依托单位: The University of Tokushima
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09680494/
• 关键词: Nuclear Fusion; Plasma-Surface Interaction; Computer Simulation; Sputtering; Erosion; Impurity Release; Secondary Electron Emission; Ion Reflection; 計算機シュミレーション; スバッタリング

A computer simulation code which treats plasma-surface interactions for divertor plates in magnetic confine-went fusion devices. The simulation code allows simultaneous incidence of different ion species as well as a Maxwellian velocity distribution and different charge states of the ions. The dynamic composition change of the surface layer due to ion implantation and redeposition of released impurities due to their ionization and gyromotion in an edge plasma.Particle release from a W test limiter exposed to deuterium edge plasma, containing impurities C and O, in the tokamak TEXTOR-94 is studied by using this simulation code. The release of W impurities from the limiter is strongly suppressed by prompt redeposition, whereas low Z impurities (C and O) are much less influenced. Expert- mentally observed radial distributions of WI and CII line intensities in front of the limiter can be explained by physical sputtering of W and deposited C, in addition to high-energy reflection of impurit … More y C ions. On the other hand, the CII line emission observed in front of graphite as a limiter is attributed to many low-energy atoms due to chemical sputtering by impact of D ions, which is strongly suppressed by deposition of high-Z impurities, such as W.Erosion of boron out of a thin film exposed to deuterium edge plasmas and the simultaneous carbon deposition in TEXTOR-94 is studied by simulation. The implantation of carbon impurities strangly changes the effective boron sputtering yield of the film, which results into a lowering of the film erosion and a formation of thick carbon deposits. A strong decrease in the experimentally observed Bill line emission around a surface location far from the plasma edge can be explained by a carbon deposition on the film. The cauculated carbon depth proflies in die film are in resonable agreement with measurements by AES.A combined Monte Carlo simulation of secondary electron emission from solids and transport of secondary electrons in a plasma sheath is performed for analyzing a relationship between the secondary electron yield and sheath voltage formed on the wall in magnetic fusion devices. Less

磁约束聚变装置偏滤器板等离子体-表面相互作用的计算机模拟程序。模拟代码允许同时入射不同的离子种类以及麦克斯韦速度分布和不同的离子电荷状态。用该程序研究了在TEXTOR-94装置中，含C和O杂质的氘边缘等离子体中，W试验限制器表面层离子注入后的动态成分变化以及释放杂质在边缘等离子体中电离和回旋运动后的再沉积。从限制器的W杂质的释放强烈抑制迅速再沉积，而低Z杂质（C和O）的影响要小得多。专家观察到的WI和CII线强度在限制器前的径向分布，除了杂质的高能反射外，还可以用W和沉积C的物理溅射来解释。 ...更多信息 y C离子。另一方面，在石墨作为限制器的前面观察到的CII线发射归因于许多低能量的原子，由于化学溅射的D离子的影响，这是强烈抑制沉积的高Z杂质，如W.侵蚀的硼暴露于氘边缘等离子体的薄膜和同时在TEXTOR-94中的碳沉积的模拟研究。碳杂质的注入奇异地改变了薄膜的有效硼溅射产率，这导致薄膜侵蚀的降低和厚的碳沉积物的形成。实验观察到的比尔线发射周围的表面位置远离等离子体边缘的强烈减少可以解释由碳沉积在膜上。利用Monte Carlo方法模拟了磁聚变装置中固体的二次电子发射和二次电子在等离子体鞘层中的输运过程，分析了二次电子产额与鞘层电压之间的关系。少

项目成果

大宅 薫: "スパッタリングと2次電子放出" プラズマ・核融合学会誌. Vol.75,No.4. (1999)

Kaoru Oya：“溅射和二次电子发射”等离子体与聚变科学学会杂志，第 75 卷，第 4 期（1999 年）。

K.Ohya, J.Kawata, A.Harada: "Dynamic simulation of sputtering of tungsten irradiated by plasmas in an oblique magnetic field" Radiation effects and Defects in Solids. Vo1.142. 401-413 (1997)

K.Ohya、J.Kawata、A.Harada：“斜磁场中等离子体辐照钨溅射的动态模拟”辐射效应和固体缺陷。

K.Ohya,J.Kawata,T.Tanabe,M.Wada,T.Ohgo,et al.: "Particle emission from a tungsten test limiter in TEXTOR-94 : a comparison between experimental and Monte Carlo simulated results" Journal of Nuclear Materials. (in press). (1999)

K.Ohya,J.Kawata,T.Tanabe,M.Wada,T.Ohgo,et al.：“TEXTOR-94 中钨测试限制器的粒子发射：实验结果与蒙特卡罗模拟结果之间的比较”核杂志

K.Ohya,J.Kawata,J.Wienhold,P.Karduck,et al.: "Boron erosion and carbon deposition due to simultaneous bombardment with deuterium and carbon ion in plasmas" Nuclear Instruments and Methods in Physics Research B. (in press). (1999)

K.Ohya,J.Kawata,J.Wienhold,P.Karduck,et al.：“由于等离子体中氘和碳离子同时轰击而导致的硼侵蚀和碳沉积”核物理研究中的仪器和方法 B.（出版中）

N.Saji, K.Ohya: "Influence of impurity deposition on ion reflection and sputtering from low Z and high Z materials" Bulletin of Faculty of Engineering, The University of Tokushima. No.44, (in press). (1999)

N.Saji、K.Ohya：“杂质沉积对低 Z 和高 Z 材料的离子反射和溅射的影响”德岛大学工程学院通报。