等离子体环境非偏置固体表面带电研究

Unbiased solid surface charging research in plasma environment

航天器与等离子体环境中的电子、离子相互作用,表面将出现充放电效应,对航天器产生负面影响.表面充电电位对充放电影响至关重要.综合考虑等离子体中粒子质量、温度及密度,二次电子效应及非偏置固体的运动速度等因素,基于气体动理论,利用粒子的麦克斯韦速度分布函数理论推导得出等离子体环境中非偏置固体表面充电电位一般表达式.分析了等离子体以及非偏置固体特殊状态下的表达式及一般状态下的表达式,总结出不同等离子环境、不同运动状态下的表面充电规律.

Within the plasma environment of spacecraft, the interaction between electrons and ions may cause surface charging and discharg- ing and may degrade the performance of spacecraft. The charging potential is a key factor for discharging process. By considering the comprehensive effects of particle mass, temperature, density of plasma, secondary electrons and the velocity of unbiased solid, a general equation of surface charging potential of unbiased solid has been derived using Maxwell velocity distribution function. The expressions under some special and general conditions have been also analyzed. The surface charging and discharging properties are summarized under different plasma environment and motion states of unbiased solid.