Protecting Spacecraft Fragments from Exposure to Small Debris

Nauka i Obrazovanie

V. V. Zelentsov¹ 

[1] Bauman Moscow State Technical University;

关键词: debris;    shield;    honeycomb;    foam;    ballistic fabric;    Kevlar;    sandwich panels;    carbon fiber;    mesh;    composite materials;   

DOI  :  10.7463/0615.0778339

来源: DOAJ

【 摘 要 】

Since the launch of the first artificial Earth satellite a large amount of space debris has been accumulated in near-earth space. This debris comprises the exhausted spacecrafts, final stages of rocket-carriers and boosters, technological space junk, consisting of the structure elements, which are separated when deploying the solar arrays, antennas etc., as well as when undocking a booster and a spacecraft. All the debris is divided into observable one of over 100 mm in size and unobservable debris. In case of possible collision with the observed debris an avoidance manoeuvre is provided. The situation with unobservable debris is worse, its dimensions ranging from 100 mm to several microns. This debris is formed as a result of explosions of dead space objects and at collisions of destroyed spacecraft fragments against each other. This debris moves along arbitrary trajectories at different speeds.

At collision of a spacecraft with fragments of small-size space debris, various consequences are possible: the device can immediately fail, suffer damages, which will have effect later and damages, which break no bones to the aircraft. Anyway, the spacecraft collision with small-size debris particles is undesirable. The protective shields are used to protect the aircraft from damage. Development of shield construction is complicated because the high cost of launch makes it impossible to conduct field tests of shields in space. All the work is carried out in the laboratory, with particles having co-impact speeds up to 10 km/s (possible speeds are up to 20 km/s) and spherically shaped particles of 0.8 ... 3 mm in diameter.

Various materials are used to manufacture shields. These are aluminum sheet, sandwich panels, metal mesh, metal foam, and woven materials (ballistic fabric). The paper considers single-layer (from sheet metal sandwich materials) and multilayer shield designs. As experimental studies show, a single-layer shield protects colliding at speeds less than 4 ... 5 km/s, at higher speeds particles breaks through them. As a result, a cloud is formed. It consists of fragments, destroying particle, and debris split-off from the obstacle. For reliable protection the sandwich panels are used. Shield design comprises two panels: the first panel being multi-layer and the second one being single-layer. The task of the first panel is to provide the maximum fragmented particle and reduce its speed. The second panel protects the structure from the cloud fragments resulting from breakdown of the first panel. The European module "Columbus” that is part of the ISS and transport vehicle ATV have the protective shield of the similar construction. The shield consists of "aluminum sheet with 2 mm thickness; filler - Kevlar + Nextel + epoxy resin, thermal insulation; the second panel comprises aluminum sheet of 3 mm thickness.

Modeling and experiments show high efficiency of steel mesh as a protective shield. Spacecraft design consists, mainly, of aluminum alloys therefore space debris is from the same material. At collision with steel mesh a particle is decelerated and destroyed. Therefore, timeRushan ability of the particle significantly decreases. The second layer, opposing to the impact of high-speed particles, is foam metal (foam-Lumina). It is successfully used in the automotive engineering. Ballistic fabric (such as Kevlar) is capable to protect from the effect of the fragmentation cloud.

【 授权许可】

Unknown