Characterization of artificial spherical particles for DEM validation studies

This paper describes a study in which advanced particle-scale characterization was carried out on spherical particles that can be used in experimental tests to validate discrete element method (DEM) simulations. Two types of particle, alkaline and borosilicate glass beads, made from two different materials, were considered. The particle shape, stiffness, contact friction properties and surface roughness were measured. The influences of hardness and roughness on the mechanical response of the particles were carefully considered. Compared to the alkaline beads, the borosilicate beads were more spherical and more uniform in size, and they exhibited mechanical characteristics closer to natural quartz sand. While only two material types were studied, the work has the broader implication as a methodology for selecting particles suitable for use in DEM studies and the key parameters that should be considered in the selection process are highlighted.

Silhouettes of alkaline glass beads generated by the QicPic.Figure optionsDownload as PowerPoint slideHighlights
► Particle scale tests were used to select materials for experimental validation of DEM codes.
► Borosilicate beads were found more spherical than alkalines and with mechanic response closer to sand.
► The role of hardness and roughness on the response of the particles was analyzed within a mechanical model.