Fluidized Bed -Top-1

Low Reynolds Number Fluidized Bed - Top.
This is a closeup of the top section of a fluidized bed. The cell is 30cm tall, by 8cm wide, by 0.8cm deep. The particles are monodisperse glass beads of diameter 309 microns, at an average volume fraction of 10%. The liquid (glycerol/water) is pumped upwards at the base of the cell through the particles to achieve fluidization. Fluidization results in a steady state system where the particles are perpetually sedimenting, and the average particle velocity is zero. The viscosity is high enough here that the Reynolds number is smaller than 1. What can be seen here are the swirling motions due to particle velocity fluctuations that spontaneously arise. The top particle/fluid interface is very sharp, and the fluctuation magnitudes approach zero at the interface

Category:

Howto & Style

Tags:

• Fluidized
• fluid
• instability
• sedimentation
• physics

[koshy2000]

very cool