托卡马克等离子体的热平衡特性与脱栏现象

本文利用欧姆加热条件下简化的能量平衡方程研究了热传导与杂质辐射的综合效应。首先指出边缘辐射带的建立与随半径增大而增大的K=nx模型紧密相关(x为电子热传导系数,n为等离子体密度),然后利用删削层中能量平衡关系确定边界温度,自洽地求解了能量平衡方程,得出的脱栏等离子体形成条件能较好地解释有关实验观察到的多种现象。

THERMAL TOKAMAK EQUILIBRIA AND DETACHED-PLASMA PHENOMENA

The combined effects of the electron thermal conductivity and the impurity radiation on ohmic heating of tokamak plasmas are studied by using a set of simplified energy balance equations. It is shown that the establishment of a radiation mantle where the total radiation power is comparable to the ohmic heating power is closely connected with a plasma thermal diffusivity increasing toward the edge. The energy balance condition in the scrape-off layer is also used to determine the electron boundary temperature T. In this way, the necessary condition for forming a detached plasma can be consistently obtained by solving the whole set of equations, and it agrees quite well with many experimental observations.