卫星介质深层充电的两类计算模型对比分析

计算模拟是评估航天器介质深层充电危害的重要研究方法之一. 通过粒子输运 模拟, 可以得到特定空间辐射环境下介质中的电荷沉积分布, 进而根据电位/电 场计算模型, 得到深层充电结果. 前期研究多是围绕RIC (辐射诱导电导率)模 型及其改进模型展开的, 而目前通常采用基于电流守恒定律的简单计算模型. 为了研究二者关系, 给出其各自求解方法, 并采用已发表数据对计算结果进行 验证; 从理论上阐述了后者是RIC模型的进一步简化, 只要二者考虑相同的介 质电导率, 则对应计算结果就是一致的; 结合GEO恶劣电子辐射环境下平板介 质模型在三类边界条件下的充电情况, 进行了充分的仿真验证. 相关结论为介 质深层充电效应评估提供了有益参考.

Comparative Analysis of Two Representative Computation Models for Deep Dielectric Charging

It is of great importance to analyze the deep dielectric charging for spacecraft using computer simulation. The general methodology is as follows. The first step is to get the charge deposition in dielectric through particle transport simulation, and then to compute the charged electric potential and electric fields according to the potential computation model. In the preliminary stage, researchers usually employed the RIC model or its improved versions for analysis, whereas the simplified model based on current conservation law has played the dominant role in recent years. In order to study the equivalence between these two classical models, the computation method for each model is presented with verification by comparing the results of a benchmark model with the published results. Then, theoretical analysis is made that the simplified model is a further simplified version of the RIC model, and they can lead to the same charging outcome providing the same total conductivity is used. Finally, through computing the charging process of a dielectric panel with three different grounding conditions under GEO severe electron radiation, sufficient simulation verifications are provided. The obtained conclusions can make beneficial reference for the evaluation of satellite deep dielectric charging.