ENERGY FLUX INTO A FLUIDIZED GRANULAR MEDIUM AT A VIBRATING WALL

We study the power input of a vibrating wall into a fluidized granular medium, using event-driven simulations of a model granular system. Th e system consists of inelastic hard disks contained between a stationa ry and a vibrating elastic wall, in the absence of gravity. Two Scalin g relations for the power input are found, both involving the pressure . The transition between the two occurs when waves generated at the mo ving wall can propagate across the system. Choosing an appropriate wav e form for the vibrating wall removes one of these scalings and render s the second very simple.