BUMPER EFFICACY AGAINST HYPERVELOCITY IMPACT OF PROJECTILES IN A SHOT LINE WITH TEMPORAL SPACING AT HIGH OBLIQUITY

摘要

A bumper is an effective shield to protect main structure against hypervelocity impact of a projectile. Its efficacy is mostly investigated for single impact, but inadequately pursued for multiple impacts despite its significance. This may be due to limitations on methodical experimentation. The paper proposes an experimental arrangement for controlled sequential impacts in a shot line for two spherical projectiles (0 6 mm) of steel. Impact velocity was around 3 km/s and obliquity was 70°, 75° and 80°. Behind 1 mm thick steel bumper, a stainless steel plate of 1.2 mm thick was kept at a distance of 10 mm as witness. Experiments are simulated in an Eulerian hydro code SPEED and the simulation results are analyzed to investigate effect of temporal spacing on damage to bumper and witness. Projectiles in contact could not perforate witness plate (80°), whereas temporally spaced projectiles could perforate witness plate.