Plasma-Wall-Interaction Diagnostics for Steady-State Fusion Plasmas

稳态聚变等离子体的等离子体壁相互作用诊断

• 批准号: 410415657
• 负责人: Dr. Sebastijan Brezinsek
• 金额: --
• 依托单位: IEK-4: Plasmaphysik
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2019
• 资助国家: 德国
• 起止时间: 2018-12-31 至 2021-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/410415657?language=en
• 关键词: Plasma; Wall; Interaction; Diagnostics; Steady

Plasma-Wall Interactions (PWI) in fusion devices, especially for future reactors with high performance and steady-state plasma operations such as ITER and CFETR, will determine the life time of Plasma-Facing Components (PFCs), impact the performance of plasmas, and govern the tritium cycle by retention. Therefore, diagnosis and understanding of the PWI processes such as material erosion, transport, and deposition as well as fuel retention by implantation and co-deposition, is crucial in order to control these processes for a safe operation of a reactor at high availability. In order to predict from the PWI in present day devices such as the EAST tokamak (Hefei, China) and the W7-X stellarator (Greifswald, Germany) to future devices numerical simulations are mandatory. Measurements in present-day experiments must be used to verify the codes and the underlying physics of PWI in order to gain confidence in the predictions. Moreover, optimized or novel diagnostics are required to be applicable for in-situ PWI analysis in long-pulse devices to permit access to crucial quantities like the fuel inventory for safety reasons.The present proposal covers the development of in-situ diagnostics systems such as Quartz-Micro Balances (QMBs) and laser-based methods inducing particle ablation (LIBS, LIAS) and testing in laboratory set-ups in China and Germany (ASIPP/Hefei, DUT/Dalian, FZJ/Jülich and HHU/Düsseldorf). QMBs measure in-situ local erosion and deposition by recording the change in the mass-sensitive resonance frequency of the quartz crystal which acts as detector. Optimization concerning thermal stability, sensitivity and calibration is required. Laser-Induced Ablation/Breakdown spectroscopy (LIAS/LIBS) can be performed in-situ and at long detection distance to monitor the hydrogen retention and impurities deposition compositions on the first wall during and between discharges. Optimization concerning the laser-material interaction time, the laser-plasma production process, and calibration is required; all must be accompanied by modelling. Optimized systems will then be integrated in the suite of diagnostics in the metallic long-pulse device EAST, such as the midplane manipulator (MAPES) and visible spectroscopic systems, and dedicated PWI experiments will be carried in the framework of this proposal. A major emphasis will be in the characterization of tungsten (W) PFCs as present in the upper divertor , where spectroscopy combined with LASER-applications and QMBs will be used to determine the major PWI processes covering W, D and seeding gases. Numerical simulations of the plasma edge with the 2D plasma fluid code SOLPS-ITER and the PWI with the 3D Monte-Carlo code ERO are performed jointly and will be applied to support the interpretation of experimental findings. Finally, the optimized and qualified diagnostics and a subset of codes will be adapted in future to the conditions of W7-X, currently operationg with graphite, and the metallic CFETR.

聚变装置中的等离子体-壁相互作用 (PWI)，特别是对于具有高性能和稳态等离子体操作的未来反应堆，例如 ITER 和 CFETR，将决定面向等离子体的组件 (PFC) 的使用寿命，影响等离子体的性能，并通过保留来控制氚循环。因此，对 PWI 过程（例如材料侵蚀、传输和沉积以及通过注入和共沉积实现的燃料保留）的诊断和理解对于控制这些过程以确保反应堆在高可用性下安全运行至关重要。为了从 EAST 托卡马克（中国合肥）和 W7-X 仿星器（德国格赖夫斯瓦尔德）等当前设备的 PWI 到未来设备的 PWI 进行预测，必须进行数值模拟。必须使用当今实验中的测量来验证 PWI 的代码和基础物理原理，以便获得对预测的信心。此外，需要优化或新颖的诊断方法适用于长脉冲设备中的原位 PWI 分析，以便出于安全原因获取燃料库存等关键量。目前的提案涵盖了原位诊断系统的开发，例如石英微量天平 (QMB) 和基于激光的粒子消融方法（LIBS、LIAS）以及在中国和德国的实验室设置中进行的测试 （ASIPP/合肥、DUT/大连、FZJ/于利希和 HHU/杜塞尔多夫）。 QMB 通过记录充当探测器的石英晶体的质量敏感共振频率的变化来测量原位局部侵蚀和沉积。需要对热稳定性、灵敏度和校准进行优化。激光诱导烧蚀/击穿光谱（LIAS/LIBS）可以在长检测距离原位进行，以监测放电期间和放电之间第一壁上的氢保留和杂质沉积成分。需要对激光-材料相互作用时间、激光-等离子体产生过程和校准进行优化；一切都必须伴随着造型。然后，优化的系统将集成到金属长脉冲设备 EAST 的诊断套件中，例如中平面操纵器 (MAPES) 和可见光谱系统，并且将在该提案的框架内进行专门的 PWI 实验。主要重点是上部偏滤器中存在的钨 (W) PFC 的表征，其中光谱学与激光应用和 QMB 相结合将用于确定涵盖 W、D 和种子气体的主要 PWI 过程。使用 2D 等离子体流体代码 SOLPS-ITER 的等离子体边缘数值模拟和使用 3D 蒙特卡罗代码 ERO 的 PWI 联合进行，并将用于支持实验结果的解释。最后，优化且合格的诊断和代码子集将在未来适应 W7-X（目前使用石墨和金属 CFETR 运行）的条件。