Bulk densities and flowability of mono-sized, binary mixtures and particle size distributions of glass spheres

The angle of repose, angle of tilting, and Hausner ratio are frequently used to estimate the flowability of a particulate material. Also, the free and tapped densities are commonly used for design and operating of particulate solids handling systems. In this study, these properties were determined for mono-sized, binary mixtures and particle size distributions of spherical glass. It was found, as in previous studies that the mono-sized properties can be described as simple functions of Archimedes number. The binary mixture tests enabled to develop empirical models to describe the properties as functions of the small particles weight ratio. They also clearly revealed that segregation was a major concern for the angle of repose experiments. By using a logistic function for the particle size distribution tests and normalizing properties by their values for mono-sized particles at the median size, a common equation describing the behavior of all the investigated properties as a function of the distribution parameter was obtained.