采用流体模型研究了外加斜磁场作用下的碰撞电负性等离子体鞘层的玻姆判据,讨论了负离子和磁场对鞘层玻姆判据的影响.研究结果表明:在电负性鞘层中,正离子更容易进入鞘层,负离子的存在只能影响离子马赫数取值的下限;而外加磁场可以使离子马赫数的取值范围整体发生移动.
The Bohm criterion for a collisinal electronegative plasma sheath in an oblique magnetic field is investigated with a fluid model. The effects of negative ions and magnetic field on the Bohm criterion are discussed.It is shown that the parameters of the negative ions affect only the lower limit for Bohm criterion,and the external magnetic field can affect the whole range of the ion Mach number values.