Final design of the JT-60SA pellet launching system for simultaneous density and ELM control
Final design of the JT-60SA pellet launching system for simultaneous density and ELM control
复制标题
用于同步密度和 ELM 控制的 JT-60SA 颗粒发射系统的最终设计
DOI：
10.1016/j.fusengdes.2018.11.041
复制
发表时间：
2019
影响因子：
1.7
通讯作者：
W. Treuterer
中科院分区：
文献类型：
--
作者：
P. Lang;T. Nakano;S. Davis;G. Matsunaga;B. Pégourié;B. Ploeckl;W. Treuterer
新型托卡马克JT-60SA的主要任务是针对ITER进行开发，并解决DEMO的关键物理和工程问题。它的弹丸发射系统是根据需求设计的，为密度分布和ELM频率的控制提供了强大而灵活的工具。建模表明，为了实现高燃料效率，必须进行板内发射，通过分析所有相关等离子体场景中潜在的颗粒燃料影响，详细阐述了满足所有任务要求的优化颗粒参数集。因此，系统布局必须适应通过导管从容器内侧注入颗粒。目前，正在努力制定最合适的解决方案，使颗粒转移损失最小化，最大转移速度，同时与正在建造的船舶施加的边界条件兼容。研究了机械离心机作为球团加速装置的可行性。这种方法将保证所需的精确颗粒发射速度，以实现对引导管传输能力的最佳适应，并精确控制到达等离子体的颗粒频率和颗粒通量。虽然离心机原理的适当性已经被几个设备证明，但拟议的版本具有采用几个加速臂的新颖设计。这样，可以实现以更高的速率和更精确地调整颗粒通量和频率的操作。此外，它允许容纳多个源，提供不同的颗粒，并同时驱动它们。适当的控制单元设计用于合并来自不同来源的颗粒，形成一个序列，以同时控制不同的基本等离子体参数，例如密度和ELM频率。这种灵活性还可以包括其他应用，如同位素分数控制或使用复合颗粒的辐射功率排放。目前，各主要部件的详细工程正在进行中，最终旨在提供规格并准备采购流程。
The key mission of the new tokamak JT-60SA is to conduct exploitations in view of ITER and to resolve key physics and engineering issues for DEMO. Its pellet launching system was designed to cover according requirements by providing a powerful and flexible tool for the control of density profile and ELM frequency. Modelling showed inboard launch is mandatory in order to achieve high fuelling efficiency, by analysing the potential pellet fuelling impact in all relevant plasma scenarios the optimized set of pellet parameters for fulfilling all the tasks requirements was elaborated. Accordingly, the systems layout had to be adapted for pellet injection via a guiding tube from the vessel inboard side. Currently, efforts are under way in order to elaborate the most appropriate solution yielding minimised pellet transfer losses and a maximum transfer speed yet compatible with boundary conditions imposed by the vessel already under construction. The feasibility of a mechanical centrifuge as pellet acceleration unit was studied. This approach would guarantee the precise pellet launch speed as needed to enable the best adaptation to the guiding tube transfer capabilities and accurate control of pellet frequency and particle flux as arriving in the plasma. While the appropriateness of the centrifuge principle has been already proven by several devices, the proposed version possesses a novel design employing several accelerator arms. Such, operation at heighten rates and with a more refined adjustment of pellet flux and frequency could be achieved. Moreover, it allows hosting several sources delivering different pellets and their simultaneous actuation. The appropriate control unit is designed to merge pellets from different sources to form a sequence for the simultaneous control of different basic plasma parameters as e.g. density and ELM frequency. This flexibility can also allow including additional applications, like isotope fraction control or radiative power exhaust by using compound pellets. At present, the detailed engineering of all major components is in progress, finally aiming to provide specifications and get ready to prepare the procurement process.