*corresponding author
Abstract: In this study, a Schulze Ring Shear Tester and the
Discrete Element Method (DEM) are employed to investigate the effect of
polydispersity on the binary shear flows. Both experimental results and
DEM simulations show that the pre-shear stresses are greater for binary
blends than for monodispersed particles. The flowability of these
mixtures is strongly affected by the solid fraction, with minimal flow
function values correlating to maximum packing fraction. However,
minimum flow function values are not observed at the same packing
fractions where the maximum pre-shear stress occurs. The powder friction
has a slightly higher contribution to powder strength than powder
adhesion, and the frictional component follows the same trend as shear
stress with mixture composition. Using DEM, it is demonstrated that the
addition of small adhesive particles reduces the averaged angular
velocity of the larger particles, which makes a contribution to the
larger shear stress for binary blends.
Keywords: Binary shear flows; Ring shear test; Discrete Element
Method