尘埃等离子体鞘层的玻姆判据

采用流体方程和自洽电荷变化模型研究了尘埃等离子体鞘层的玻姆判据. 讨论了离子临界马赫数和尘埃粒子临界马赫数随尘埃密度变化的关系, 以及尘埃表面势随尘埃密度变化的趋势. 由于鞘边尘埃粒子的存在, 离子必需以大于声速的速度进入鞘层; 随尘埃密度的持续增加, 离子的临界马赫数增加到一个最大值后开始逐渐减小. 数值计算得到的结果满足Sagdeev势的定性分析. 关键词： 等离子体 鞘层 玻姆判据

The Bohm criterion for the dusty plasma sheath

The hydrodynamic-fluid model and the self-consistent dust charging model are used to investigate the Bohm criterion for the dusty plasma sheath. The variation of the ion critical Mach number and the dust Mach number with dust density are presented, and the relation between the dust surface potential and the dust density at the sheath edge is discussed. It is shown that the ion velocity entering the sheath would exceed the ion sound velocity due to the existence of dust particles. The ion critical Mach number began declining after a maximum with the incessant increase of the dust density. The numerical results satisfy the qualitative analysis of the Sagdeev potential.