hypervelocity impact, hypervelocity projectile, film structure, large space structure, space debris, fragment, railgun, spacecraft construction material, damage assessment, impact damage
その他のタイトル(英)
Experimental study on hyper-velocity impact on film structure
Tokai University
Tokai University
Tokai University
Japan Aerospace Exploration Agency Institute of Space and Astronautical Science
Japan Aerospace Exploration Agency Institute of Space and Astronautical Science
出版者
宇宙航空研究開発機構宇宙科学研究本部
出版者(英)
Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency (JAXA/ISAS)
雑誌名
第24回宇宙エネルギーシンポジウム 平成16年度
雑誌名(英)
The Twenty-fourth Space Energy Symposium March 7, 2005
ページ
62 - 66
発行年
2005-06
抄録(英)
For large scale space structures such as large antennas and solar power satellites in the future, light-weight film structures will be widely used. Since there are a lot of meteoroids and debris in orbit, the hyper-velocity impact to the structure cannot be avoided especially in the near earth orbit. We have performed a series of hyper-velocity impact experiments to study the impact phenomena using the thin film structures. The experiments have been conducted using the rail-gun at the Institute of Space and Astronautical Science/JAXA. The film target in vacuum chamber was set at 3.3 m in front of the rail-gun exit. We used two sizes of film targets, 50 mm square and 100 mm square with 25 micrometer and 125 micrometer in thickness. They were supported at the upper edge or at all edges to study the effect of the boundary condition. A Styrofoam block is placed at 100 mm behind the film target to catch the fragments from film target. The size of the block is 200 mm x 200 mm x 100 mm with a hole at the center (50 mm or 60 mm in diameter) to let the projectile pass through the hole without impact to the block. In the experiment, we found three types of damage in the hyper-velocity impact on the styrofoam. A lot of small holes distributed around the center hole were always observed in the experiments. Two types of melting damage, in circular or rectangular area, were observed in many cases. We found that the circular melting was generated by the plasma injected from the rail-gun. When the speed of the projectile was less than 5 km/s, the surface of the Styrofoam was not melt by the impact. But, when the velocity of the projectile exceeded 5 km/s, the Styrofoam was melt asymmetrically in a large area. The experimental results suggested that the size of the fragments was smaller when the velocity of the projectile was relatively higher. The scattering angle of the fragments was almost constant when the velocity of the projectile was less than 5 km/s, but the angle got larger when the velocity was faster than 5 km/s. When the velocity of the projectile was smaller than 5 km/s, the film target broke up into fragments which spread within 0.5 rad. When the velocity was faster than 5 km/s, the film target broke up into fragments and hot gas which spread in an angle larger than 0.5 rad. The damage by the gas was observed only near the surface of the Styrofoam, but the fragments were penetrated into the Styrofoam, giving deeper damage.