Modeling and Damage/Failure Control of Spacecraft Pressurized Structures Subject to Orbital Debris Impact

轨道碎片的危害是国际上对天基基础设施安全性和可靠性日益关切的问题-由于碰撞速度非常高，平均约为11公里/秒，即使是很小的粒子也可能损坏、降解或摧毁航天器。地球轨道上的人造物体数量稳步增加，由于2007-2009年发生的一系列事件，在过去四年中处理这个问题变得更加重要。今天，空间监视网络正在跟踪19，000多个直径约为10厘米或更大的物体。据估计，有超过300，000个直径大于1厘米的无法追踪的物体，还有数百万个直径小于1厘米的物体[2]。 对执行使命的航天器在空间碎片环境中进行防护是最传统的方法。从概念上讲，它包括一个缓冲器，放置在一个小的距离，从压力墙。屏蔽和加压壁穿孔的情况下，航天器故障的潜在可能性。 拟议的研究方案将侧重于屏蔽低压航天器加压舱的结构完整性，部分侧重于具有高内压的航天器机载系统的充气压力容器。 申请人将模拟多层防护系统的穿透过程以及与加固压力墙上的冲击损伤形成相关的开裂现象。 建议的模拟程序和软件将作为一种工具来预测结构的响应，并使设计师能够开发的“结构+屏蔽”的配置，提供“简单的穿孔”条件下，没有爆裂的情况下，屏蔽和加强容器壁穿孔。

The hazard from orbital debris is a growing international concern for the safety and reliability of space-based infrastructure - even small particles can damage, degrade, or destroy spacecraft due to the very high velocities involved in a collision, on the average about 11 km/sec . The number of man-made objects in Earth orbit has increased steadily, and it has become a lot more crucial to get a handle on the subject over the past four years because of the series of incidents happened in 2007-2009. Today the Space Surveillance Network is tracking more than 19,000 objects approximately 10 centimeters in diameter or larger. It is estimated that there are over 300,000 untrackable objects with a diameter larger than one centimeter, and millions smaller [2]. Shielding is a most traditional method of protection of spacecraft developed for a mission into space debris environment. Conceptually it consists of a bumper that is placed at a small distance away from the pressure wall. The case of both shield and pressurized wall perforation presents a potential for the spacecraft failure. The proposed research program will be focused on the structural integrity of the shielded low-pressure spacecraft pressurized modules and partially on the gas-filled pressure vessels for onboard spacecraft systems with high internal pressure. The applicant will simulate the process of penetration of the multi-layered protective system and cracking phenomena associated with the formation of the impact damage on the reinforced pressure wall. The proposed simulation procedure and software will serve as a tool to forecast the response of structure and enable the designer to develop the "structure+shield" configurations which provide "simple perforation" conditions without bursting in cases where the shield and reinforced vessel wall are perforated.