The isotope effect on ion temperature gradient mode in CFQS

doi:10.16568/j.0254-6086.202403017

Abstract

Abstract: Based on Chinese First Quasi-axisymmetric Stellarator (CFQS), we carry out the study of isotope effect on ion temperature gradient (ITG) mode in quasi-axisymmetric stellarator by using the gyrokinetic Vlasov simulation code GKV. The simulation results show that there is an obvious isotope effect on ITG in CFQS. The growth rate of ITG decreases significantly with the increase of the mass of hydrogen isotope. To scan the plasma parameters in CFQS, such as the content of the heavier hydrogen isotope in the mixed plasma, density gradient, and ion-to-electron temperature ratio, we study impact of these parameters on isotope effect. Otherwise, we also study the isotope effect of ITG in different toroidal angles and different radial positions of CFQS, and the results reveal the isotope effect of ITG is universal in CFQS.

Key words: Isotope effect, Ion temperature gradient mode, Quasi-axisymmetric stellarator, CFQS

摘要： 基于中国首台准环对称仿星器(CFQS)，利用回旋动理学弗拉索夫代码 GKV 率先开展准环对称仿星器中离子温度梯度模(ITG)的同位素效应研究。模拟结果表明，CFQS 中存在明显的 ITG 同位素效应，随着氢同位素质量的增加，ITG 的增长率显著下降。通过扫描等离子参数，如不同氢同位素混合的比例、密度梯度以及离子与电子温度比，研究了这些等离子体参数下 CFQS 中同位素效应的变化。此外，在不同的环向或径向位置处研究了 CFQS 的三维磁场位形对 ITG 同位素的影响，发现 ITG 的同位素效应在不同的环向和径向位置均普遍存在。

关键词: 同位素效应；离子温度梯度模；准环对称仿星器；CFQS

CLC Number:

TL61+ 2

QIN Cheng, HUANG Jie, LI Mo-shan . The isotope effect on ion temperature gradient mode in CFQS[J]. Nuclear Fusion and Plasma Physics, 2024, 44(3): 359-366.

覃程, 黄捷, 李沫杉. CFQS 中离子温度梯度模的同位素效应研究 [J]. 核工业西南物理研究院, 2024, 44(3): 359-366.

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