Tokamak中自举电流的剖面准直性

The alignment of bootstrap current in tokamak

利用Harris模型 ,通过求解等离子体平衡方程 ,计算俘获粒子份额 ,分别对常规剪切和中心负剪切下tokamak中的自举电流的大小和剖面准直性进行了计算和分析 .自举电流分布与等离子体平衡电流分布之间的剖面准直性可以通过调整等离子体的密度、温度和电流分布参数 ,以及描述等离子体形状的拉长度k和三角变形因子d来获得 .中心负剪切位形有利于自举电流产生 ,并有好的剖面准直性 .通过计算比较 ,分别在常规剪切位形下和中心负剪切位形下获得了一组优化的等离子体参数 ,在这组参数下 。

By calculating the trapped particle fraction, solving the Grand\|Shafranov equation describing plasma equilibrium, and using Harris model, the magnitude and alignment of the bootstrap current in tokamak are calculated and analysed under the conventional shear regimes and also the negative central shear regimes. The conclustion we obtained are: through adjusting the profile parameters of plasma density, temperature and current, and the elongation k and triangularity d which describe the plasma shape, the alignment of bootstrap current profile with the equilibrium current profile can be produced; the negative central shear regimes are advantage ous to produce bootstrap current, and the profile of bootstrap current is well\|aligned with the equilibrium current profile. By comparing our calculated results, the optimized parameters are obtained under the conventional shear and the negative central shear regimes.