JET internal transport barriers: experiment vs theory
JET internal transport barriers: experiment vs theory
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JET 内部运输障碍：实验与理论
DOI：
10.1088/0741-3335/45/6/307
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发表时间：
2003
影响因子：
2.2
通讯作者：
K. Zastrow
中科院分区：
文献类型：
--
作者：
B. Esposito;F. Crisanti;V. Parail;P. Maget;Y. Baranov;A. Becoulet;C. Castaldo;C. Challis;R. Angelis;X. Garbet;C. Giroud;N. Hawkes;E. Joffrin;X. Litaudon;D. Mazon;M. Riva;K. Zastrow
为了确定表征屏障处湍流稳定性的主要特征，我们对多种带有内部传输屏障 (ITB) 的 JET 放电进行了分析。研究发现，势垒位置与E×B流剪切速率超过离子温度梯度模式不稳定性（γηi）线性增长率的区域有很好的相关性。一个关键点是 γηi 对磁剪切的依赖性：在该数据库的放电中，与非常低或零磁剪切相关的 γηi 的减少有利于 ITB 的形成。 ITB形成后，发生正反馈，其中E×B流剪切机制起主导作用，势垒的位置可能不再与低剪切区域相关。
A large variety of JET discharges with internal transport barriers (ITBs) has been analysed in order to determine the main features which characterize turbulence stabilization at the barrier. It is found that the location of barriers is well correlated with regions where the E×B flow shearing rate exceeds the linear growth rate of the ion temperature gradient mode instability (γηi). A key point is the dependence of γηi on the magnetic shear: in the discharges of this database the reduction of γηi associated to very low or null magnetic shear favours the formation of an ITB. After the ITB formation a positive feedback occurs in which the E×B flow shear mechanism has the leading role and the position of the barrier may be no longer linked to the low shear region.