Investigation of phase modulation and propagation-route effect from unmatched large-scale structures for Doppler reflectometry measurement through 2D full-wave modeling

To interpret the common symmetric peaks caused by the large-scale structure in the complex S(f) spectrum from the heterodyne Doppler reflectometry(DR) measurement in EAST, a 2D circular-shaped O-mode full-wave model based on the finite-difference time-domain method is built. The scattering characteristics and the influences on the DR signal from various scales are investigated. When the structure is located around the cutoff layer, a moving radial or poloidal large-scale structure k_θ■...     

EAST中性束注入下快离子输运行为的研究

利用等离子体输运分析程序TRANSP和粒子导心轨道模拟程序ORBIT,结合聚变中子和等离子体储能诊断数据,对EAST(Experimental Advanced Superconducting Tokamak)托卡马克中性束注入加热时不同等离子体电流和纵场强度下的快离子输运行为进行了研究。实验和模拟结果表明:中性束反向束注入时的快离子初始轨道损失功率大于中性束同向束;中性束4条束线产生快离子初始轨道损失区域主要集中在装置中平面以下第一壁以及偏滤器区域;在EAST目前的运行参数范围内,提高等离子体电流和纵场强度,可以使等离子体中快离子的漂移轨道宽度和拉莫尔回旋半径缩小,更有利于快离子的约束,从而提高中性束的加热效率,增加聚变中子产额和等离子体储能。