Abstract:

Projectile impact and penetration in a 2D granular bed under the acceleration due to gravity was been studied by fast video photograph and acceleration sensors. The distribution of displacement of the granular bed after impact can be clearly observed by highspeed video photograph. Granular jet formation and the penetration regime of the projectile shown in the experiment,  reflect the properties of energy dissipation of granular mediums. The acceleration sensor can directly measure drag forces of the projectile in the movement, and  these forces compare with hydrostatic drag forces during penetration. Experimental data obtained by comparison showed that considerable drag forces act on the projectile and these forces are related to velocity.

Key words: particulate matter; impact; flow