Impulse penetration into idealized granular beds: Behavior of cumulative surface kinetic energy

The propagation of δ function mechanical impulses in idealized three-dimensional hexagonal close packed lattices of monosized Hertz sphere was investigated using particle dynamics based simulation. The kinetic energy behavior of grains at cumulative surface of a granular bed after the generation of a normal impulse into the bed was also analyzed. It was found that the cumulative average kinetic energy per surface grain, κ, decreased with the penetration of the impulse into the bed. The results show that the minimum value of κ depends upon restitutional losses at the grain contacts.