低杂波电流驱动的密度极限分析

DENSITY LIMIT ANALYSIS FOR LOWER HYBRID CURRENT DRIVE

用低杂波的可近性条件、参量不稳定性条件和功率耦合谱分析了低杂波电流驱动（ＬＨＣＤ）。由于波的可近性条件限制耦合谱中平行相速度较大的波进入等离子体中心，参量不稳定性使平行相速度较低的波与离子相互作用，随着等离子体密度的增加，这些作用越来越明显。最终导致低杂波不能在中心与电子相互作用，驱动电流消失，这就是所谓密度极限。在本文建立的模型基础上的计算结果与实验结果符合较好。

The conditions of wave accessibility and parameter decay instability are used to analyse the density limit in LHCD. The proposed mechanism is based on the combination between accessibility, which increasingly limits N from the lower end of LHW power spectrum, and the onset of parameter decay to the ion quasi-mode, which limits N from the upper end of LHW power spectrum. Comparisons with experimental results are made.