权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Theoretical and experimental studies on internal charging/discharging phenomena occurring spacecraft material

航天器材料内部充放电现象的理论与实验研究

基本信息

批准号：
14205140
负责人：
TOMITA Nobuyuki
金额：
$ 20.88万
依托单位：
Musashi Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14205140/
关键词：
Internal charging Monte-Carlo method Electron beam Dielectric material モンテカルロ法

项目摘要

In order to simulate the space radiation environment, the high vacuum chamber (2002) and the electron gun (2003) were installed. Electron irradiation tests on several dielectric materials such as Kapton and Teflon were carried out and the charge distributions inside the materials were obtained using the measurement technique previously developed by the present research group. Tests on glass material used for the cover glass on solar panels were also carried out. The results indicate that there exists a peak of charge density inside the dielectric material and high electric field and electric potential are induced due to the electron irradiation. The penetration depth of the charge becomes deeper as the incident electron energy increases. The charge density profiles inside glass materials vary according to the composition, but clear relationship between the profile and the component has not been revealed. The internal charging database is going to be organized using the data obtained. As for theoretical point of view, the physical model for collision between incoming electrons and atoms consisting the dielectric material was constructed based on consideration of the quantum theory. Numerical simulations based on the model were carried out using the Monte-Carlo methodology. Each electron injected onto the material surface is tracked based on the statistical estimations, and the trapped electrons are counted to construct charge density distribution. A PC-based parallel computer was installed in 2002 to execute this calculation because this type of simulation requires huge memories and high CPU performance. The simulation results show the electron accumulation process, but quantitative agreement of charge profile compared to that obtained by the experiments were not obtained. The detailed investigation clarified that the excessive ionization occurred among the collision processes and thus the positive charge near the irradiated surface were observed.

为了模拟空间辐射环境，安装了高真空室（2002）和电子枪（2003）。对Kapton和Teflon等几种介电材料进行了电子辐照测试，并使用本研究小组先前开发的测量技术获得了材料内部的电荷分布。还对用于太阳能电池板盖板玻璃的玻璃材料进行了测试。结果表明，介电材料内部存在电荷密度峰值，并且由于电子辐照而感应出高电场和电势。随着入射电子能量的增加，电荷的穿透深度变得更深。玻璃材料内部的电荷密度分布随成分的不同而变化，但分布与成分之间的明确关系尚未揭示。将使用获得的数据来组织内部收费数据库。就理论角度而言，基于量子理论的考虑，构建了入射电子与构成介电材料的原子之间碰撞的物理模型。使用蒙特卡罗方法进行基于该模型的数值模拟。根据统计估计跟踪注入到材料表面的每个电子，并对捕获的电子进行计数以构建电荷密度分布。 2002 年安装了一台基于 PC 的并行计算机来执行这种计算，因为这种类型的模拟需要巨大的内存和较高的 CPU 性能。模拟结果显示了电子积累过程，但与实验获得的电荷分布相比并未获得定量一致性。详细调查表明，碰撞过程中发生了过度电离，因此在照射表面附近观察到了正电荷。