COMPREHENSIVE STUDY OF TOROIDAL FUSION SYSTEM

本研究计划为期三年，主要围绕以下四个方面开展工作：（1）基于回旋动力学粒子模型的磁约束等离子体模拟程序的开发。(2)为国家聚变科学研究所正在建造的大型螺旋装置（LHD）开发微波反射计。(3)根据NIFS的JIPP T-IIU和UCLA的CCT的实验结果，对LHD进行约束改进的方案。(4)基于螺旋系统的聚变堆概念设计。(1)NIFS和UCLA物理系合作开发了一个三维回旋运动粒子程序。结果表明，该模拟程序可用于研究与MHD模式有关的等离子体运动。它成为可能与此代码来模拟稳定的内部扭结模式，以及destabiliz 关于我们 阿尔芬波的高能离子的存在。当轴上的安全值q小于1时，该程序可以解释磁场重联引起的磁岛的生长和磁轴上等离子体的损失。(2)微波反射计是测量等离子体中电子密度分布和密度起伏的有力手段。使用X模式的反射计的优点是能够测量低密度区域，例如分界线的外部，这被认为与H模式转变和离子回旋加速器加热实验有很强的联系。讨论了该方法在美国加州大学洛杉矶分校电气工程系和美国通用原子公司DIII-D托卡马克装置运行中的适用性和相关问题。(3)美国加州大学洛杉矶分校开发并转移到NIFS的渗硼方法已应用于JIPP T-IIU和CHS的真空室内表面处理。边缘等离子体和表面等离子体相互作用的控制被发现有希望的应用这种方法来LHD等离子体约束改善。(4)美国加州大学洛杉矶分校等离子体与聚变研究中心进行了基于托卡马克系统的核聚变反应堆概念设计。通过与UCLA相关科学家的讨论，推进了基于螺旋系统的反应器设计。少

The 3-year program has been carried out on the following four subjects which are urgently important for the nuclear fusion research : (1) Development of simulation codes based on the gyro-kinetic particle model, for the purpose of investigating the behavior of a magnetically confined plasma. (2) Development of microwave reflectometer for Large Helical Device (LHD) which is under construction at the National Institute for Fusion Science (NIFS). (3) Scenarios for confinement improvement on LHD, based on the experimental results of JIPP T-IIU at NIFS and CCT at UCLA. (4) Conceptual design of a fusion reactor based on helical system.(1) A three dimensional gyro-kinetic particle code has been developed by the collaborative work between NIFS and Physics Department of UCLA. It has been proved that this simulation code is applicable to the study of plasma motions related with MHD modes. It becomes possible with this code to simulate the stabilization of internal kink mode as well as destabiliz … More ation of Alfven waves by the presence of high energy ions. The code can explain the growth of magnetic islands by magnetic field reconnection and the related loss of plasma on the magnetic axis when the safety value q on the axis is made lower than 1.(2) The microwave reflectometer is a powerful means to measure the electron density profile as well as density fluctuations in a plasma. The use of X-mode for the reflectometer has an advantage of being able to measure the low density region such as outside of a separatrix, which is believed to have a strong connection with H-mode transition and ion cyclotron heating experiments. The applicability and related problems are discussed at Electric Engineering Department of UCLA and General Atomics where the DIII-D tokamak is under operation.(3) The boronization method which has been developed at UCLA and transferred to NIFS has been applied to the inner surface treatment of vacuum chambers of JIPP T-IIU and CHS at NIFS. The control of edge plasma and surface plasma interaction is found promising to the application of this method to LHD plasma confinement improvement.(4) A conceptual design of nuclear fusion reactor based on the tokamak system has been carried out at Plasma and Fusion Research Center of UCLA. The reactor design based on the helical system has been promoted by the discussion with related scientists at UCLA. Less