Bulk densities and flowability of non-spherical particles with mono-sized and particle size distributions

The angle of repose, angle of tilting, and Hausner ratio are frequently used to estimate the flowability of particulate materials. In addition, free and tapped densities are commonly used for the design and operation of systems for handling particulate solids. In this study, these properties were determined for mono-sized and particle size distributions of three non-spherical particle materials. Based on previous and additional new measurements with new size fractions of mono-sized particles, it was found that mono-sized properties can be described as simple new functions (replacing the previous correlations) of the Archimedes number. Mixtures with wider size distributions were defined using logistic functions based on the median size and distribution parameter. Normalizing the measured property by the median size and assuming it to be mono-sized enabled finding a simple relation to the distribution parameter, equivalent to that found for spherical particles. Thus, the appropriate properties can be predicted based on the size distribution.