Optimization of Divertor

偏滤器优化

• 批准号: 11210205
• 负责人: OHYABU Nobuyoshi
• 金额: $ 10.94万
• 依托单位: National Institute for Fusion Science
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research on Priority Areas
• 财政年份: 1999
• 资助国家: 日本
• 起止时间: 1999 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-11210205/
• 关键词: Divertor pumping; Hydrogen superpermeation; Membrane; Ion sputtering; Impurity deposition; Helical Divertor; Heliotron Device; GradB drift; Uragan-3M; Bx∇Bドリフト; ダイバータ粒子束の非対称性; V属金属; 水素透過・吸蔵; ニオブ; バナジウム; トロイダB×▽Bドリフト; 高速イオンの直接損失; 水素排気; 超透

Particle control in divertor region is of great importance for production and confinement of high performance plasma in magnetic confinement device. In order to develop a new type of divertor pumping system with a "superpermeation", which is the interaction between V-group metal membranes and hydrogen atoms, we carried out plasma-membrane experiments on basic surface physics and proof-of-principle experiments on hydrogen pumping in divertor region in fusion devices. In the divertor region, high-energy ion sputtering and impurity (metal and carbon) deposition on the membrane surface can be usually seen for vacuum components. The influence of such events on hydrogen permeation performance of membrane is investigated in the basic plasma-membrane experiments. The degradation of hydrogen permeation rate is observed and the method to improve the permeation rate is also found in the experiments. On the other hand, hydrogen particle pumping with a Nb membrane has been first time in the world d … More emonstrated in the divertor plasma in the JFT-2M tokamak. This suggests that the membrane pumping system is available in the divertor region. As a result, we have a possibility in prospect to realize a membrane pumping system or a panel pumping system as a divertor pumping method.We have studied properties of divertor plasma in the Heliotron type, large and small devices (LHD, Uragan-3M). In the divertor configuration, the heat and particle flows eventually on to the divertor plates. We find that the heat deposition patterns on the divertor plates are not up-down symmetric. Degree of the asymmetry is higher for the smaller device (Uragan-3M) with higher RF power. The asymmetry is reversed with reversal of the magnetic field. These observations are explained by the direct (non-diffusive) loss (the Bx∇B drift) of the ion from the confinement volume. The density and potential fluctuations in the edge beyond the last closed surface are measured by the probes. The particle flux estimated by the fluctuation measurement is comparable to that evaluated from the particle balance. Furthermore more than 50 % of the particle loss due to the fluctuations take place during the burst phase. Less

转移区域中的粒子控制对于在磁性限制装置中高性能血浆的生产和限制至关重要。为了开发一种具有“超级耐药性”的新型分离泵系统，这是V基团金属膜和氢原子之间的相互作用，我们对融合设备中分离器区域的氢气泵的基本表面物理学和原始实验进行了等离子体 - 膜实验。在分离区域，通常可以在真空成分上看到高能离子溅射和杂质（金属和碳）沉积。在基本的等离子体膜实验中研究了此类事件对膜渗透性能的影响。观察到氢渗透率的降解，并且在实验中还发现了提高渗透率的方法。另一方面，在世界上首次使用NB膜泵送氢颗粒……在JFT-2M Tokamak的转移等离子体中更有证明。这表明膜抽水系统可在分流区域提供。结果，我们有可能实现膜抽水系统或面板抽水系统作为分离泵送方法。我们已经研究了Heliotron类型中移动等离子体的特性，大小的小型设备（LHD，Uragan-3M）。在分离构型中，热和粒子有时会流向分离板。我们发现，分流板上的热沉积模式不是对称的。对于具有较高RF功率的较小设备（Uragan-3M）的不对称程度较高。不对称以磁场的反向反转。这些观察结果是由离子的直接（非排除）损失（BX∇B漂移）中的。在最后一个封闭表面以外的边缘的密度和潜在波动是由问题测量的。通过波动测量估计的粒子通量与从粒子平衡中评估的磁通量相当。此外，由于波动造成的颗粒损失的50％以上是在爆发阶段发生的。较少的

项目成果

N. Ohyabu, et al.: "Active Control of Hydrogen Recycling by the Permeation and Absorption Techniques"Proc. of International Workshop on Hydrogen Recycling at Plasma Facing Materials. (to be published).

N. Ohyabu 等人：“通过渗透和吸收技术主动控制氢回收”Proc。

Hydrogen Release through Metallic Surface : the Role of Sputtering and Impurity Dynamics

通过金属表面释放氢：溅射和杂质动力学的作用

• 发表时间: 2004
• 期刊: Physica Scripta T108
• 作者: Nakajima;H.;et al.;A.I Livshits
• 通讯作者: A.I Livshits

E.L.Sorokovoy: "Density and potential fluctuations in the edge plasma of the Uragan-3M torsatron"Problems of Atomic Science and Technology, Series Plasma Physics. 5. 6 (2002)

E.L.Sorokovoy：“Uragan-3M 托萨管边缘等离子体的密度和电位波动”原子科学与技术问题，系列等离子体物理。

S.Masuzaki: "Review of initial experimental results of the PSI studies in the Large Helical Device"Journal of Nuclear Materials. 290-293巻. 12-16 (2001)

S.Masuzaki：“大型螺旋装置 PSI 研究的初步实验结果回顾”，核材料杂志，第 290-293 卷（2001 年）。

DIVERTOR FLOW AND PARTICLE LOSS BEHAVIORS IN SPONTANEOUS CHANGE OF CONFINEMENT STATE IN THE URAGAN-3M TORSATRON

URAGAN-3M TorSATRON 约束状态自发变化中的转向器流动和颗粒损失行为

• 发表时间: 2005
• 期刊: Problems of Atomic Science and Technology, Series : Plasma Physics (11),No.2
• 作者: V.V.Chechkin;et al.
• 通讯作者: et al.