Measurement of electron particle transport coefficients in different operational modes of DIII-D
Measurement of electron particle transport coefficients in different operational modes of DIII-D
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DOI：
10.1088/0029-5515/38/4/301
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发表时间：
1998-04
期刊：
影响因子：
3.3
通讯作者：
D. Baker;M. Wade;G. Jackson;R. Maingi;R. Stockdale;J. Degrassie;R. Groebner;C. Forest;G. Porter;DIII-D Team
中科院分区：
文献类型：
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作者：
D. Baker;M. Wade;G. Jackson;R. Maingi;R. Stockdale;J. Degrassie;R. Groebner;C. Forest;G. Porter;DIII-D Team
在DIII-D托卡马克装置上得到了不同工作模式下的电子输运系数。操作模式为：双零转向（DND）低约束（L模）、无边缘局域模（ELM-free）的DND高约束（H模）、单零转向（SND）ELM-free H模和泵浦SND ELMing H模。研究了血浆电流和安全系数（q）曲线的各种值。对于L模式和ELMing H模式，通过在边缘处调制氘气的喷流获得系数。对于ELM自由模式，通过分析L-H跃迁后电子密度分布的时间演化得到的系数。结果清楚地表明，电子扩散系数的径向分布取决于DIII-D的操作模式。不同托卡马克操作模式之间的输运系数的径向依赖性的差异是显着的。在L模式和ELMing H模式下，扩散系数随半径增大而增大。在ELMing H模式下，扩散系数随着q的边缘值而增加。L模式的边缘处的值约为ELMing H模式的两倍。在ELM自由H模式下，扩散系数在约0.8的归一化半径之外迅速减小。在无ELM H模式的（相对大的）误差条内，DND和SND等离子体之间的扩散系数没有可测量的差异。
Electron transport coefficients have been obtained for different operational modes on the DIII-D tokamak. The operational modes are: double null diverted (DND) low confinement (L mode), DND high confinement (H mode) without edge localized modes (ELM-free), single null diverted (SND) ELM-free H mode and pumped SND ELMing H mode. Various values of plasma current and safety factor (q) profiles were investigated. For the L mode and ELMing H mode, the coefficients were obtained by a modulated puff of deuterium gas at the edge. For the ELM-free modes, the coefficients were obtained by analysing the temporal evolution of the electron density profile immediately after the L-H transition. The results show clearly that the radial profile of the electron diffusion coefficient depends on the operational mode of DIII-D. The difference in the radial dependences of the transport coefficients between the different tokamak operational modes is significant. In the L mode and the ELMing H mode, the diffusion coefficient increases with radius. In ELMing H mode, the diffusion coefficient increases with the edge value of q. The value at the edge for L mode is about twice that for ELMing H mode. In ELM-free H mode, the diffusion coefficient decreases rapidly outside a normalized radius of about 0.8. Within the (relatively large) error bars for ELM-free H mode, there is no measurable difference in diffusion coefficient between the DND and SND plasmas.