Recycling and wall pumping in long duration discharges on TRIAM-1M
Recycling and wall pumping in long duration discharges on TRIAM-1M
复制标题
TRIAM-1M 上长时间放电的回收和壁泵
DOI：
10.1088/0029-5515/42/2/307
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发表时间：
2002
期刊：
影响因子：
3.3
通讯作者：
H. Nakashima
中科院分区：
文献类型：
--
作者：
M. Sakamoto;S. Itoh;K. Nakamura;H. Zushi;K. Hanada;E. Jotaki;Y. Pan;S. Kawasaki;H. Nakashima
对低（?1018?）M-3)和高(?1019？m-3)密度长持续等离子体在TRIAM-1M。各等离子体的循环系数随时间增加。循环系数的时间演化存在两个时间常数。一个是几秒，另一个是30秒左右。计算出低密度和高密度等离子体的壁抽运速率为？1.5?1016？原子m - 2 ?S-1和？4?1017？原子m - 2 ?s - 1。这种差异可能是由扩散离子总数和能量小于0.7 keV的电荷交换中性通量引起的。在超长放电(70？Min)时，循环系数变为1或更大，然后再次降至1以下，即墙体重复饱和刷新过程。在高功率和高密度实验中，观察到壁饱和现象。受壁饱和度限制的放电持续时间随密度的增加而减小。
Recycling and wall pumping have been studied comparing low (?1018?m-3) and high (?1019?m-3) density long duration plasmas in TRIAM-1M. The recycling coefficient of each plasma increases with time. There exist two time constants in the temporal evolution of the recycling coefficient. One is a few seconds and the other is about 30?s. The wall pumping rates of low and high density plasmas are evaluated to be ?1.5?1016?atoms m-2?s-1 and ?4?1017?atoms m-2?s-1, respectively. The difference may be caused by the total number of diffused ions and the charge exchange neutral flux with an energy of less than 0.7?keV. In an ultra-long discharge (?70?min), the recycling coefficient becomes 1 or more before again decreasing below 1, i.e. the wall repeats the process of being saturated and refreshed. In high power and high density experiments, wall saturation phenomena have been observed. The discharge duration limited by wall saturation decreases with an increase in density.