Model of Sand Transport by Consecutive Particle Collisions with Wind Interaction
Résumé
We study successive collisions of incident energetic beads with granular packing in the context of Aeolian saltation transport. We investigate the collision process for the case where the incident bead and those from the packing have identicalmechanical properties.We analyze the features of the consecutive collision processes. We used a molecular dynamics method known as DEM (soft Discrete Element Method) with an initial static packing of 20;000 2D particles. The packing is created randomly in a box of dimension 250 60 disk diameters. The incident disks are launched at a given p velocity ranging between 25 and 100 (normalized by g:d) and an angle of 15ı with random position on top of the flowing zone. Few disks are launched to initiate the dilation of the upper surface. This situation due to the previous collisions is responsible for a need of less input energy for maintaining the flow by ejecting new disks from the static bed. This new behavior is obtained by the presence of the wind which can accelerates the flowing disks during their ballistic trajectories.