A perspective on vibration-induced size segregation of granular materials

Abstract

Segregation of particulate mixtures is a problem of great consequence in industries involved with the handling and processing of granular materials in which homogeneity is generally required. While there are several factors that may be responsible for segregation in bulk solids, it is well accepted that nonuniformity in particle size is a fundamental contributor. When the granular material is exposed to vibrations, the question of whether or not convection is an essential ingredient for size segregation is addressed by distinguishing between the situation where vibrations are not sufficiently energetic to promote a mean flow of the bulk solid, and those cases where a convective flow does occur. Based on experimental and simulation results in the literature, as well as dynamical systems analysis of a recent model of a binary granular mixture, it is proposed that "void-filling" beneath large particles is a universal mechanism promoting segregation, while convection essentially provides a means of mixing enhancement.

The Fragmentation Energy-Fan Model in Quarry Blasts

“…However, this may not be too large compared with other errors in size measurement by image analysis, e.g. segregation and sifting (Rosato et al 1987(Rosato et al , 2002Möbius et al 2001;Liffman et al 2001;Metzger et al 2011), overlapped fragments (Thurley and Ng 2008;Andersson and Thurley 2008), capturing (Chavez et al 1996;Thurley 2002), segmentation disintegration and fusion (Eden and Franklin Fig. 3 Perfomance of online mass measurements; m R is the mass hauled by the trucks to the plant and m pp is the mass processed by the plant given by the belts scales Fig.…”

Experimental study of particle size segregation in 2D granular materials under vertical vibrations

“…"Segregation" is one of the interesting phenomena observed when a homogeneous bulk solid constituted from a variety of species or components evolves from an initially mixed state to a presumed non-uniform state owing to the relative movement within the materials [3,4]. This is an unwanted phenomenon often occurring in many industrial areas associated with the handling and processing of granular mixtures such as pharmaceuticals, food processing, geophysics, material sciences, and almost all engineering fields.…”

“…This is an unwanted phenomenon often occurring in many industrial areas associated with the handling and processing of granular mixtures such as pharmaceuticals, food processing, geophysics, material sciences, and almost all engineering fields. In fact, it must be realized that a complete particle mixing is the major purpose required in many industrial processes, rather than the unwanted segregation of the mixtures [3][4][5][6]. Although we have accepted for a long time that the segregation phenomena in granular media occurs from a difference of their physical properties (e.g.…”

“…size, density, shape, etc. ), a significant factor to control segregation in many industrial processes is the particle size [3,[5][6][7].…”

Discrete and continuum descriptions of shaken granular matter

“…Overall, a wide range of complex phenomena has been reported, presenting both similarities and fundamental divergences from regular fluids. For general overviews we refer the reader to available reviews that treat the subject [29,58,59].…”