An experimental investigation of convective instabilities in fluidized beds
Hudson, Joe Louis
Master of Science
This work outlines the construction and operation of a water fluidized bed in which convective instabilities can be studied quantitatively. The apparatus is made in such a way that bed width, distributor thickness and distributor pressure drop can be varied independently. The apparatus is rectangular with one dimension being narrow enough to suppress any instabilities in that direction. Thus, the fluidized bed is two-dimensional with respect to convective instabilities. The majority of experimentation was qualitative with experiments being designed to confirm a reproducible method of operation. Qualitatively, it was observed that the intensity of convection in an unstable bed depends upon the values of certain bed parameters. Also, the appearance of instabilities is very sensitive to the bead packing in the near vicinity of the support screen. A small amount of quantitative experimentation was done, comparing the experimental results to the predictions of a mathematical stability analysis. The preliminary experimental results were in good agreement with the general trends of the stability analysis..