From MHD regime to quiescent non-inductive discharges in Tore Supra: experimental observations and MHD modelling
From MHD regime to quiescent non-inductive discharges in Tore Supra: experimental observations and MHD modelling
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DOI：
10.1088/0741-3335/51/6/065005
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发表时间：
2009-06
影响因子：
2.2
通讯作者：
P. Maget;G. Huysmans;H. Lütjens;M. Ottaviani;P. Moreau;J. Ségui
中科院分区：
文献类型：
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作者：
P. Maget;G. Huysmans;H. Lütjens;M. Ottaviani;P. Moreau;J. Ségui
在 Tore Supra 上运行非感应等离子体放电的尝试有时会失败，因为会触发磁流体动力学 (MHD) 不稳定性，这种不稳定性会大幅饱和，从而产生约束退化和波驱动快速电子的损失（所谓的 MHD 状态（Maget 等人 2005 Nucl. Fusion 45 69–80））。在本文中，我们从实验观察中研究了向这种软（非破坏性）MHD 极限的转变，并将其与非线性代码预测进行比较。这样的比较表明，具有周期性松弛或饱和的不同非线性状态可以被正确理解。然而，如果在计算中使用实际传输系数，则无法再现 q = 2 处没有可检测磁岛的成功非感应放电。额外的物理学似乎必须解释这些放电，例如抗磁效应，这也可以证明突然过渡到 MHD 状态的情况是合理的。
Attempts to run non-inductive plasma discharges on Tore Supra sometimes fail due to the triggering of magneto-hydro-dynamic (MHD) instabilities that saturate at a large amplitude, producing degraded confinement and loss of wave driven fast electrons (the so-called MHD regime (Maget et al 2005 Nucl. Fusion 45 69–80)). In this paper we investigate the transition to this soft (in the sense of non-disruptive) MHD limit from experimental observations, and compare it with non-linear code predictions. Such a comparison suggests that different non-linear regimes, with periodic relaxations or saturation, are correctly understood. However, successful non-inductive discharges without detectable magnetic island at q = 2 cannot be reproduced if realistic transport coefficients are used in the computation. Additional physics seems mandatory for explaining these discharges, such as diamagnetic effects, that could also justify cases of abrupt transition to the MHD regime.