DEM Study on the effect of particle‐size distribution on jamming in a 3D conical hopper

Abstract

Despite the advancement on the understanding on the unwelcome phenomenon of hopper jamming, the influence of the particle‐size distribution (PSD) width of the ubiquitous continuous PSDs remains unknown. Accordingly, this study investigated using discrete element method a range of PSD widths (10%≤σ/μ≤50%) of lognormal PSDs with a constant mean particle diameter of 10 mm in a three‐dimensional hopper. Results indicate that, although the monodisperse particles of 10 mm diameters do not jam, the wider PSDs (σ/μ≥30%) jam. The flatter arches and higher mass‐averaged force that are linked to the denser packing of wider PSDs underlie the propensity to jam. To reduce the jamming probability, the friction coefficient and initial fill height can be reduced, but not changes in particle density. The results here highlight that the mean particle diameter alone is an insufficient parameter to predict jamming and the impact of PSD width is non‐negligible. © 2018 American Institute of Chemical Engineers AIChE J, 65: 512–519, 2019