A tangential fast visible camera has been set up in EAST tokamak for the study of edge MHD instabilities such as ELM. To determine the 3-D information from CCD images, Tsai＇s two-stage technique was utilized to calib...A tangential fast visible camera has been set up in EAST tokamak for the study of edge MHD instabilities such as ELM. To determine the 3-D information from CCD images, Tsai＇s two-stage technique was utilized to calibrate the high-speed camera imaging system for ELM study. By applying tiles of the passive stabilizers in the tokamak device as the calibration pattern, transformation parameters for transforming from a 3-D world coordinate system to a 2-D image coordinate system were obtained, including the rotation matrix, the translation vector, the focal length and the lens distortion. The calibration errors were estimated and the results indicate the reliability of the method used for the camera imaging system. Through the calibration, some information about ELM filaments, such as positions and velocities were obtained from images of H-mode CCD videos.展开更多
在共振磁场扰动(resonant magnetic perturbation,RMP)控制边界局域模(edge localized modes,ELMs)的试验中,在ELMs被缓解的条件下,研究了RMP对电子热输运的影响。结果表明,RMP对等离子体的输运增强集中在边界位置。从电子回旋辐射诊断...在共振磁场扰动(resonant magnetic perturbation,RMP)控制边界局域模(edge localized modes,ELMs)的试验中,在ELMs被缓解的条件下,研究了RMP对电子热输运的影响。结果表明,RMP对等离子体的输运增强集中在边界位置。从电子回旋辐射诊断给出的电子温度中观察到,ELMs的每次爆发均会引起边界电子温度的崩塌且崩塌沿等离子体径向向内传播,传播速度不受RMP影响。通过指数函数拟合方法,对电子温度崩塌后的恢复过程进行分析,得到了恢复特征时间,并用该恢复特征时间近似表征输运特征时间。在RMP投入期间,边界位置处的恢复特征时间变短,电子热输运增强。输运的增强因子沿径向向外增大,在边界处达到3.5。展开更多
基金supported by National Natural Science Foundation of China(No.11275047)the National Magnetic Confinement Fusion Science Program of China(No.2013GB102000)
文摘A tangential fast visible camera has been set up in EAST tokamak for the study of edge MHD instabilities such as ELM. To determine the 3-D information from CCD images, Tsai＇s two-stage technique was utilized to calibrate the high-speed camera imaging system for ELM study. By applying tiles of the passive stabilizers in the tokamak device as the calibration pattern, transformation parameters for transforming from a 3-D world coordinate system to a 2-D image coordinate system were obtained, including the rotation matrix, the translation vector, the focal length and the lens distortion. The calibration errors were estimated and the results indicate the reliability of the method used for the camera imaging system. Through the calibration, some information about ELM filaments, such as positions and velocities were obtained from images of H-mode CCD videos.
文摘在共振磁场扰动(resonant magnetic perturbation,RMP)控制边界局域模(edge localized modes,ELMs)的试验中,在ELMs被缓解的条件下,研究了RMP对电子热输运的影响。结果表明,RMP对等离子体的输运增强集中在边界位置。从电子回旋辐射诊断给出的电子温度中观察到,ELMs的每次爆发均会引起边界电子温度的崩塌且崩塌沿等离子体径向向内传播,传播速度不受RMP影响。通过指数函数拟合方法,对电子温度崩塌后的恢复过程进行分析,得到了恢复特征时间,并用该恢复特征时间近似表征输运特征时间。在RMP投入期间,边界位置处的恢复特征时间变短,电子热输运增强。输运的增强因子沿径向向外增大,在边界处达到3.5。
