空间微小碎片对低轨道航天器太阳电池表面撞击损伤研究

Investigation on the surface damage to solar cells by impacts of space micro-debris on low earth orbit

低轨道空间微小碎片密度相对较高,对太阳电池等大面积暴露材料的累积撞击损伤效应是航天器设计中应考虑的主要问题之一.以典型的太阳同步轨道为例分析和计算了太阳电池表面所遭遇的微小碎片通量,进行了微小碎片的撞击损伤模拟实验,并建立了撞击损伤方程.根据碎片通量分布及撞击损伤方程计算了微小碎片的超高速撞击所产生的太阳电池表面的面积损伤率,通过光学透射率的实验测试并结合理论模型,对碎片导致的太阳电池光学透射率衰减进行了计算和分析.结果表明,10a累积撞击导致的太阳电池表面的面积损伤率平均约为0.61%,严重时达到2.3%;光学透射率衰减平均为0.5%,严重时可达到1.5%.此外,针对典型实例就太阳电池表面损伤问题给出了一种模式计算和实验模拟相结合的评估方法.

Cumulative damage to the exposed spacecraft materials by the micro-debris on low earth orbit, where the debris is densely populated, is one of the crucial problems calling for due consideration in designing of spacecrafts. The flux of micro-debris encountered by a typical sun-synchronous vehicle was calculated, the associated hypervelocity impact simulation experiment was carried out, and the damage equation was established. Based on the flux result and the damage equation, the surface damage ratio of the solar call due to micro-impacts was calculated, and the associated optical transmittance decrease of the cell was evaluated according to optical measurement and theoretical model. The result showed that the surface damage ratio of solar cell after 10 a cumulative micro-impacts reaches 0.61% on average, and up to 2.3 % in the worst case. The optical transmittance decreases by 0.5% on average, and up to 1.5% in the worst case. In this paper, a quantitative method of evaluation for the issue of solar cell＇s surface damage due to micro-impacts was demonstrated through a concrete example.