Experimental and Numerical Investigations of the Shear Behavior of
Binary Particle Blends
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.