等离子体模型碰撞项的比较

本文在两种碰撞模型(BGK模型和LB模型)下,计算了碰撞对等离子体色散方程的影响。碰撞的主要作用是使色散函数Z(ξ)变为广义色散函数W(ξ,ν)。分析比较了两种模型下广义色散函数的性质。讨论了碰撞对低频漂移波(局域模)和离声波稳定性的影响。分析表明,LB模型不仅在物理上更为合理,而且在计算及表达形式上也比BGK模型更为简明。 关键词：

COMPARISION OF TWO COLLISION MODELS IN PLASMA

In this paper, the effects of collision on the dispersion equation of plasma are discussed under two kinds of collision models (BGK model and LB model). Analysis shows that the main effect of collision is to change the usual dispersion function Z(ξ) into a generalized one W(ξ,ν). The properties of W function have been analysed and compared for two models. The effects of collision on low frequeny drift wave (local mode) and ion-acoustic wave have been discussed. It is shown that LB model is not only more reasonable physically than BGK model, but also more simple in calculation and expression.