Optimization of Helical Magnetic Configuration

为了在该项目下进行富有成效的国际合作，我们设置了两个子项目：（1）在螺旋轴构型中使用ECCD方法开发用于电流控制的ECH和ECE分析工具，（2）开发用于抑制螺旋轴构型中等离子体波动的等离子体波动数据库。我们与CIEMAT合作开发了一个射线追踪程序（TRECE），用于分析三维磁场中ECH微波的能量吸收。利用该程序和部分支持的ECE辐射计，对Heliotron J的热输运进行了研究。在子项目（2）中，对Heliotron J、TJ-II和U-3 M三台不同结构的装置进行了协同实验，主要研究了边缘等离子体湍流，并采用了一种通用的诊断方法。这项合作发现了边缘等离子体湍流特性的一些相似性和差异性。同时指出了边缘等离子体湍流的一个共同特征--间歇性，即Levy指数对边缘等离子体湍流的分类是有效的。新的诊断方法和/或波动研究的分析技术已被提出，并与一些这样的方法进行了试点研究。

In order to make fruitful international collaborations under this project, we set two sub-projects: (1) Development of tools for ECH and ECE analyses for current control by using the ECCD method in helical-axis configurations, (2) Development of plasma fluctuation database for suppression of plasma fluctuation in helical-axis configurations.Under the sub-project (1), we have developed a ray-tracing code (TRECE) under the collaboration with CIEMAT to analyze ECH power absorption of ECH microwaves in three-dimensional magnetic fields configuration. By using this code and ECE radiometer equipped through a partial support from this project, the study of heat transport in Heliotron J has been progressed. The code has been improved to analyze ECCD experiments in Heliotron J.Under the sub-project (2), Collaborative experiments among three devices with different configurations (Heliotron J, TJ-II and U-3M) have been performed mainly focused on the edge plasma turbulence, where a common diagnostic method has been used. This collaboration has found out some similarities and differences in the characteristics of edge plasma turbulence. It is also pointed out the effectiveness of Levy Index to classify the edge plasma turbulence with intermittent nature, which is one of common features in the edge plasma turbulence. New diagnostic methods and/or analyzing technique for the fluctuation study have been proposed and pilot studies with some of such methods have been performed.