Fundumantal Research for Dynamic Engalic Dovertas

动态 Engalic Dovertas 的基础研究

基本信息

批准号：
09308018
负责人：
TAKAMURA Shuichi
金额：
$ 20.29万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A).
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 2000
项目状态：
已结题

项目摘要

1. Hydrogen recycling in long-pulse tokamak dischargeBy applying the static or rotating helical magnetic field, the surface area contacting with the plasma was found to increase so that the fresh wall surface enhances the wall pumping.2. Magnetic island formation due to rotating helical magnetic perturbationWhen the relative poloidal velocity between the tokamak plasma and the rotating helical field is relatively small, the growth of tearing-mode by magnetic reconnection produces finally the formation of magnetic island. It deforms the equilibrium magnetic flux surface so that the plasma current may be modulated in radial and poloidal directions. Such a modulation has been detected through an amplification of perturbed radial magnetic field. The redistribution of plasma current due to magnetic island development has been clearly observed at the main resonance layer of magnetic helicity.3. Enhanced attenuation of penetrating perturbed magnetic fieldWhen the relative poloidal velocity me … More ntioned in the previous section is large and the electron temperature at the resonance layer is relatively high, the screening current flows at this resonance layer so that a strong attenuation of penetrating external magnetic perturbation has been observed. The magnetic perturbation with a fixed frequency produces either a magnetic island formation or an attenuation of helical field, depending on the direction of field rotation. Such an attenuation has been thought not only by a main resonance at m/n=6/1 but also by some contributions from the side-band modes of m/n=7/1, 8/1 generated by the toroidal effect, which has been investigated numerical modelling.4. Temporal modulation of electron temperature profileThe deformation of magnetic flux surface due to island formation generates temporal modulation of the radial profile of electron temperature. The effect with and without magnetic island formation may produces different behaviors, which has been investigated now.5. Excitation of shear Alfven waves and other phenomenaThe shear Alfven resonance is located at very close to the magnetic resonance layer. The magnetic field enhancement due to Alfven resonance has been tried to be detected by observing the radial component of perturbed magnetic field at a toroidal section without local helical winding. There have been observed some enhancement close to the Alfven resonance layer. The phase information on the 2-D poloidal cross-section has been investigated to make clear the contribution of Alfven resonance. Less

1. 长脉冲托卡马克放电中的氢气回收通过施加静态或旋转螺旋磁场，发现与等离子体接触的表面积增加，从而使新鲜的壁表面增强了壁泵浦。2．磁扰动当托卡马克等离子体与旋转螺旋场之间的相对极向速度较小时，磁重联导致的撕裂模式的增长最终导致磁岛的形成。使平衡磁通量表面变形，从而可以在径向和极向方向上调制等离子体电流。通过放大扰动径向磁场，可以清楚地观察到由于磁岛形成而导致的等离子体电流的重新分布。磁螺旋性的主共振层。3．当相对极向速度较大且电子时，穿透扰动磁场的增强衰减。由于谐振层的温度相对较高，屏蔽电流在该谐振层流动，因此可以观察到穿透性外部磁扰动的强烈衰减。具有固定频率的磁扰动会产生磁岛形成或螺旋场的衰减。，取决于场旋转的方向，这种衰减不仅由 m/n=6/1 处的主谐振引起，而且还由 m/n=7/1, 8 的边带模式的一些贡献引起。 /1 生成4．电子温度分布的时间调制由于岛的形成而产生的磁通量表面的变形产生了电子温度的径向分布的时间调制，有或没有磁岛形成的效应都可能产生。 5.剪切阿尔文波的激发和其他现象剪切阿尔文共振位于非常接近磁共振层的地方，已经尝试了由阿尔文共振引起的磁场增强。通过观察没有局部螺旋缠绕的环形截面处的扰动磁场的径向分量可以检测到靠近阿尔文共振层的一些增强。已经研究了二维极向截面上的相位信息。清除阿尔文共振的贡献。