Characterizing the intrinsic properties of powder – A combined discrete element analysis and Hall flowmeter testing study

Abstract

Discrete element modelling (DEM) and experimental characterization were carried out for Hall flowmeter tests, in which Inconel718 powders were poured down through a funnel into a density cup to form a heap. By measuring the flow rate, angle of repose and packing fraction from the experiments, and combining with DEM simulations, we were able to extract the coefficients of friction for the powder-powder and powder-wall interactions. We further studied the effect of powder-powder adhesion and found that the adhesion could greatly affect the flow rate and flow pattern. In particular, by increasing the adhesion, we observed a transition from a continuous to discontinuous discharging flow, and revealed an underlying mechanism for the transition. We also studied the effects of powder size and density cup diameter, and found that at their application size scale, the influences of these parameters on the measured results are negligible. The present work presents a simple approach to study the intrinsic properties of powders, and their influences on flowability and packing property.