Role of core radiation during slow oscillations in LHD
Role of core radiation during slow oscillations in LHD
复制标题
LHD 缓慢振荡过程中核心辐射的作用
DOI：
10.1088/0029-5515/41/5/305
复制
发表时间：
2001
期刊：
影响因子：
3.3
通讯作者：
O. Motojima
中科院分区：
文献类型：
--
作者：
B. Peterson;Y. Nakamura;K. Yamazaki;N. Noda;J. Rice;Y. Takeiri;M. Goto;K. Narihara;K. Tanaka;Kuninori Sato;S. Masuzaki;S. Sakakibara;K. Ida;H. Funaba;M. Shoji;M. Osakabe;M. Sato;Y. Xu;T. Kobuchi;N. Ashikawa;P. Vries;M. Emoto;H. Idei;K. Ikeda;S. Inagaki;N. Inoue;M. Isobe;S. Kado;K. Khlopenkov;S. Kubo;R. Kumazawa;T. Minami;J. Miyazawa;T. Morisaki;S. Murakami;S. Muto;T. Mutoh;Y. Nagayama;H. Nakanishi;K. Nishimura;T. Notake;Y. Liang;S. Ohdachi;Y. Oka;T. Ozaki;R. Pavlichenko;A. Sagara;K. Saito;R. Sakamoto;H. Sasao;M. Sasao;T. Seki;T. Shimozuma;H. Suzuki;M. Takechi;N. Tamura;K. Toi;T. Tokuzawa;Y. Torii;K. Tsumori;I. Yamada;S. Yamaguchi;S. Yamamoto;M. Yokoyama;Y. Yoshimura;K. Watanabe;T. Watari;K. Kawahata;O. Kaneko;N. Ohyabu;H. Yamada;A. Komori;S. Sudo;O. Motojima
在使用不锈钢导流板的LHD实验中，在NBI加热的长脉冲放电过程中，观察到等离子体参数缓慢（~1 s）的循环振荡，称为“呼吸”等离子体。利用平均离子、电晕平衡模型计算铁杂质冷却速率，根据LHD放电的电子温度、密度分布和辐射分布数据，计算出在0.0 <ρ<0.8时的铁杂质密度分布。计算出的铁密度与电子密度相振荡，在ρ = 0.4附近达到峰值，电子密度的变化系数为4。这与铁的光谱测量结果在定性上是一致的，后者显示出类似的振荡。铁杂质浓度与电子温度变化以及辐射与束流沉积之间的局部功率平衡的相关性表明，当铁杂质的辐射主导局部功率平衡时，核心等离子体被冷却。当导流板电子温度超过溅射阈值时，振荡阶段计算铁密度的增加表明不锈钢导流板的溅射可能是铁杂质的来源。改变输运的证据表明，需要更仔细地研究杂质输运在这种振荡中的作用。
During experiments in LHD using stainless steel divertor plates, a slow (~1 s) cyclic oscillation in the plasma parameters known as `breathing' plasma was observed during NBI heated long pulse discharges. Using an average ion, corona equilibrium model for the iron impurity cooling rate, the iron impurity density profile is calculated for 0.0 <ρ<0.8 from the measured electron temperature and density profiles and radiation profile data for these discharges in LHD. This calculated iron density oscillates out of phase with the electron density and peaks near ρ = 0.4 at a fraction of the electron density that varies by a factor of 4. This is in qualitative agreement with spectroscopic measurements of iron that show a similar oscillation. The correlation of the iron impurity concentration with the change in electron temperature and with the local power balance between radiation and beam deposition indicates that when radiation from the iron impurity dominates the local power balance the core plasma is cooled. The increase in the calculated iron density during the phase of the oscillation when the divertor electron temperature exceeds the sputtering threshold suggests that sputtering of the stainless steel divertor plate may be the source of the iron impurity. Evidence of changing transport points to the need for a closer examination of the role of impurity transport in this oscillation.
S. Sudo、Y. Nagayama、M. Emoto、M. Goto、Y. Hamada、K. Ida、T. Ido、H. Iguchi、S. Inagaki、M. Isobe、K. Kawahata、K. KMopenkov、S.
DOI：
--
发表时间：
--
期刊：
影响因子：
--
作者：
通讯作者：
--