Granular instability in fluidized beds: A small-over-large instabilityFor different particle diameters arranged in a gas fluidized bed, a new gravitational instability is predicted. The first order stability analysis yields conditions for growth of the most unstable wavenumber both as a function of particle diameter and dimensionless Bond number. Gravity acts to distribute the greater fluid mass associated with smaller particles, while surface tension stabilizes the entire bed against accelerations. The phenomenon, called the 'Small-over-Large' (SL) instability, evolves somewhat akin to a Rayleigh-Taylor mechanism and in addition to fundamental interest, carries implications for predicting solute redistribution and gravitational alignments in particle beds and chemical separation columns.
Document ID
19940005780
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Noever, David A. (NASA Marshall Space Flight Center Huntsville, AL, United States)
Date Acquired
September 6, 2013
Publication Date
August 1, 1992
Publication Information
Publication: ESA, Proceedings of the 8th European Symposium on Materials and Fluid Sciences in Microgravity, Volume 2