航天器迎风面不同位置原子氧掏蚀效应的数值模拟研究

Kapton作为基底的热控涂层被广泛应用于航天器的外表层设计中。近地轨道航天器的飞行方向与航天器表面法线之间的夹角(在本文中简称为ANI)对原子氧掏蚀效应有较大的影响。文章利用Monte Carlo方法研究了航天器迎风面(即0°≤ANI≤90°处)上ANI与掏蚀效应之间的关系。结果表明,束流和撞击能量不变时,ANI的增加会引起原子氧掏蚀空腔发生同向倾斜,空腔的深度不断减小,而宽度将急剧增加;当保护层厚度一定时,ANI的增加还会引起缺陷处入射的原子氧的反应率降低。

Numerical simulation of atomic oxygen undercutting on the front surface of spacecraft

Kapton is usually used on the surface of spacecraft as a base material of thermal control coatings. Undercutting is considered to be the major form of atomic oxygen damage to protective Kapton in LEO space according to flight experiments carried out by NASA, and the angle of attack relative to normal incidence (ANI) has a great influence on undercutting effect of atomic oxygen. In this paper, Monte Carlo method is used to study the relation between ANI and undercutting effect of atomic oxygen on the surface of spacecraft when ANI ranges from zero to ninety degrees. Results indicate that with fixed fluence and energy of atomic oxygen, the undercut cavity tilts and the depth of the cavity decrease with the increase of ANI, the width of the cavity increases sharply and the amount of the atomic oxygen entering the cavity falls off with increase of ANI when the thickness of protective coatings is kept unchanged.