等离子体中的迁移系数

TRANSPORT COEFFICIENTS IN PLASMAS

从等离子体动力学方程出发,采用玻尔兹曼碰撞项,在粒子分布函数偏离麦克斯韦分布甚小的情况下,作三级矩近似得到了等离子体迁移方程组。迁移方程组中忽略时间微分项后,得出了电子-离子等离子体的张量形式迁移系数,以及与磁场方向成平行(∥)、垂直(⊥)和交叉方向的迁移系数。导出的结果和文献[1]采用朗道碰撞项得出的结果进行了比较。结果表明,迁移系数和等离子体参数的依赖关系是一致的,但对磁场B和离子电荷Z_i值取定时,个别迁移系数要差一倍。此外,导出的迁移系数形式比文献[1]的要简单些。

In this paper, plasma transport equations are derived under the condition that the collision term in the equation is taken as Boltzmann form and the distribution function is approximately Maxwellian.Neglecting the time derivative term , we get the formula of transport coefficients. Then we have compared our results with those in refferences [1] and [2]. It is shown that the dependence of transport coefficients on plasma parameters is almost the same, but the specific values of some coefficients are different from those in references [1] and [2].