Image analysis of packed beds of spherical particles of different sizes

Two-dimensional simulations of packed beds composed of binary and ternary p article mixtures were made and image analysis of the bed structure was used to determine the bed porosity and tortuosity. Both the porosity and tortuo sity were found to be dependent upon the volume fraction of the large parti cles. However, the volume fraction alone does not totally determine either the porosity or the tortuosity. For a bed of two different sizes of particl es, its tortuosity may be considered a product of two quantities, the macro - and micro-tortuosity, each of which can be determined from the correspond ing monosized particle beds. (C) 1999 Published by Elsevier Science B.V. Al l rights reserved.