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arXiv · 1608.08946

Length scale of density waves in the gravitational flow of fine grains in pipes

Erick de Moraes Franklin·Carlos Azael Alvarez Zambrano
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Abstract

Gravitational flow of grains in pipes is frequently encountered in industry. When the grains and pipes are size-constrained, granular flow may result in density waves consisting of alternate high- and low-compactness regions. This paper discusses the length scale of density waves that appear when fine grains fall vertically in pipes. A one-dimensional model and a linear stability analysis of the model are presented. The analysis suggests the presence of long-wavelength instability for the most unstable mode, moreover, a cut-off wavenumber from which the length scale is estimated. Finally, the model results are compared to experimental data.

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Erick de Moraes Franklin, Carlos Azael Alvarez Zambrano. 2016-08-31. Length scale of density waves in the gravitational flow of fine grains in pipes. https://doi.org/10.1007/s40430-014-0291-3

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