Modeling of the control of the driven current profile in ICRF MCCD on EAST plasma
Modeling of the control of the driven current profile in ICRF MCCD on EAST plasma
复制标题
EAST 等离子体上 ICRF MCCD 驱动电流分布控制的建模
作者：
尹岚;C. Yang;龚学余;路兴强;曹锦佳
在先进的托卡马克装置中，电流分布的控制是改善约束和抑制不稳定性的关键问题。利用先进超导托卡马克实验装置的典型放电数据，采用全波方法和Ehst-Karney效率公式，对离子回旋频率范围内的模式转换电流驱动（MCCD）中的驱动电流分布控制进行了数值模拟。结果表明，移动模式转换层可以有效地改变MCCD中的驱动电流分布。通过改变射频频率和少数离子浓度，可以将驱动电流的峰值定位在归一化的小半径范围内（−0.60≤r/a≤0）的目标位置。通过优化，离轴MCCD的效率可以达到233 kA/MW，模式转换离子回旋波在这种情况下起着重要的作用。研究了电子温度和等离子体密度对驱动电流分布的影响，电流分布的控制对于改善先进托克马克运行中的约束和抑制不稳定性至关重要。利用先进超导托卡马克实验装置的典型放电数据，采用全波方法和Ehst-Karney效率公式，对离子回旋频率范围内的模式转换电流驱动（MCCD）中的驱动电流分布控制进行了数值模拟。结果表明，移动模式转换层可以有效地改变MCCD中的驱动电流分布。通过改变射频频率和少数离子浓度，可以将驱动电流的峰值定位在归一化的小半径范围内（−0.60≤r/a≤0）的目标位置。通过优化，离轴MCCD的效率可以达到233 kA/MW，模式转换离子回旋波在这种情况下起着重要的作用。研究了电子温度和等离子体密度对驱动电流分布的影响。
Control of the current profile is a crucial issue for improved confinement and the inhibition of instability in advanced tokamak operation. Using typical discharge data for the Experimental Advanced Superconducting Tokamak, numerical simulations of driven-current profile control in mode conversion current drive (MCCD) in the ion cyclotron range of frequencies were performed employing a full-wave method and Ehst–Karney efficiency formula. Results indicate that the driven current profile in MCCD can be effectively modified by shifting the mode conversion layer. The peak of the driven current can be located at an aimed position in the normalized minor radius range (−0.60≤r/a≤0) by changing the radiofrequency and the minority-ion concentration. The efficiency of the off-axis MCCD can reach 233 kA/MW through optimization, and the mode converted ion cyclotron wave plays an important role in such scenarios. The effects of electron temperature and plasma density on the driven current profile are also investigated.Control of the current profile is a crucial issue for improved confinement and the inhibition of instability in advanced tokamak operation. Using typical discharge data for the Experimental Advanced Superconducting Tokamak, numerical simulations of driven-current profile control in mode conversion current drive (MCCD) in the ion cyclotron range of frequencies were performed employing a full-wave method and Ehst–Karney efficiency formula. Results indicate that the driven current profile in MCCD can be effectively modified by shifting the mode conversion layer. The peak of the driven current can be located at an aimed position in the normalized minor radius range (−0.60≤r/a≤0) by changing the radiofrequency and the minority-ion concentration. The efficiency of the off-axis MCCD can reach 233 kA/MW through optimization, and the mode converted ion cyclotron wave plays an important role in such scenarios. The effects of electron temperature and plasma density on the driven current profile are also investigated.