Numerical study of bidisperse cohesive particle blends—Bulk properties and critical thresholds

We present a numerical study of bulk properties of binary particle blends via DEM. Properties of settled particle bulks, such as packing fraction, are computed. We investigated the effects of components size ratio, their relative mass fraction and the cohesion of smaller particles on bulk properties. Below a critical value of the mass fraction, bulk properties are independent of small particle properties. This value is connected with the particle contact network and is inversely proportional to the size ratio. Two critical thresholds in the Bond number exist, determining the dependence of bulk properties on relative mass fraction. For Bond numbers below unity, the effect of cohesion can be neglected. Above it, bulk properties reverse their dependency on small particles’ mass fraction proportionally to the cohesion strength. Finally, bulk properties measured become independent of small particles’ relative concentration when their cohesion strength is large enough to sustain a large particle.