DISTRIBUTION OF NEAREST NEIGHBORS IN DILUTE SUSPENSIONS OF MONODISPERSE SPHERES
A model is proposed to describe the distribution of distances between nearest neighbors in random-packed low-density assemblies of equal-sized spheres. The model is based on the probability of not finding any sphere center in an arbitrary volume of a given size. This probability contains a limiting packing density, <I>φ<SUB>m</SUB></I>, as a fitting parameter. The physical meaning of <I>φ<SUB>m</SUB></I> is the solids concentration above which every particle in the suspension is in contact with at least one of its neighbors. It means that at solids concentration <I>φ</I> = <I>φ<SUB>m</SUB></I> the fraction of particles whose motions are constrained by the presence of any other contacting particles becomes unity. The value of <I>φ<SUB>m</SUB></I> is evaluated from nearest neighbor distributions in random assemblies of spheres obtained by computer simulation. The closeness of the resulting value, <I>φ<SUB>m</SUB></I> = 0.52, to that reported by Probstein <I>et al.</I> (1994) from viscosity measurements leads to the possibility of interpreting the empirical viscosity correlations in terms of the local arrangement of particles in the suspension.
- Journal of chemical engineering of Japan
Journal of chemical engineering of Japan 29(3), 416-420, 1996-06-30
The Society of Chemical Engineers, Japan