chapter  8
28 Pages

Fundamental Forces in Powder Flow

WithN. Stevens, S. Tedeschi, M. Djomlija, B. Moudgil

This chapter reviews the fundamental theory of powder flow and its characterization, the underlying forces relevant to particle cohesion, their relationship to bulk properties, and state-of-the-art research to understand and control powder behavior. The topic of powder flow behavior has been a subject of interest for many centuries. Early research on powder properties dates back to Reynolds, Prandlt, Coulomb, and Mohr. Powder flow properties have significant influence on many unit operations in modern industry including filtration, grinding, mixing, and agglomeration. Powder flow properties have significant influence on many unit operations in modern industry including filtration, grinding, mixing, and agglomeration. Powders are neither solid, liquid, nor gas; however, they have traits of each associated with them. Powders are not a solid, although they have strength and can withstand some deformation. There are a number of different direct shear testers that have been developed to characterize powder flow.