(85d) Descent of Intruders in Vibrated Gas Fluidized Beds

We investigated the descent of intruder particles in pseudo-2D vibrated gas fluidized beds. Intruders descended with an oscillating velocity with the descent velocity varying with vertical position in the fluidized bed. We attribute the varying descent velocity to varying particle packing fraction at different locations in the fluidized bed. We also found that the intruder descent velocity decreases dramatically as the intruder is moved closer to a side wall. We also investigated the interaction of two intruders finding high levels of interaction, including a phenomenon similar to drafting-kissing-tumbling observed in Newtonian fluids.