Anomalous tungsten transport driven by ion temperature gradient turbulence
Anomalous tungsten transport driven by ion temperature gradient turbulence
复制标题
离子温度梯度湍流驱动的异常钨输运
DOI：
10.1088/1741-4326/ac4557
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发表时间：
2021
期刊：
影响因子：
3.3
通讯作者：
T. Watanabe
中科院分区：
文献类型：
--
作者：
Shaokang Xu;S. Maeyama;T. Watanabe
本研究表明，基于非线性回旋模拟的反常钨粒子输运与线性回旋研究有一些相似之处，但也存在一些显着差异。特别是，线性稳定模式的非线性激发在异常钨粒子输运中起着不可忽视的作用。突出的结果是零钨粒子输运的临界密度梯度的下移和向外钨粒子输运的极向剖面的修改，这两者都与小尺度湍流波动有关。前一种是由于线性稳定模产生的向外粒子对流。后者是由线性稳定模式和具有有限膨胀角的大尺度涡流共同带来的，它使粒子扩散的极向轮廓变平，并进一步将最强的向外粒子传输的峰值位置移动到高极向角区域。
The present study reveals that the anomalous tungsten particle transport based on the nonlinear gyrokinetic simulations shares some similarities with that of the linear gyrokinetic study, meanwhile there exists some significant differences. In particular, nonlinear excitation of the linearly stable modes plays a non-negligible role in the anomalous tungsten particle transport. The highlighted results are the downshift of the critical density gradient for zero tungsten particle transport and the modification of the poloidal profile of the outward tungsten particle transport, which are both related to the small scale turbulent fluctuations. The former one is due to the outward particle convection produced by the linearly stable modes. The later one is brought by both the linearly stable modes and the large-scale eddies with finite ballooning angle, which flatten the poloidal profile of the particle diffusion and further shift the peak positions of the strongest outward particle transport to the high poloidal angle regions.