Numerical simulation of liquid transfer between particles

Liquid transfer between particles plays a central role in the operation of a variety of particle processing equipment, including flotation, spray-coating, flocculation, granulation, and drying. In each of these applications, the local liquid concentration within the bed dramatically affects the flow behavior of the system and can strongly impact performance. In this work, we introduce a dynamic liquid transfer model for use in discrete element modeling (DEM) of heterogeneous particle systems. We explicitly track moisture levels on individual particles and utilize an experimentally validated rule-set for liquid transfer upon forming/breaking contacts. As a test of this new model we present results from the simulation of a rotary drum spray-coating system, but expect that this liquid transfer-modified DEM is general and would be applicable to wide range of processing operations.

Graphical abstractHere we describe and test a model for liquid transfer in heterogenous particle systems. Our model relies on two plausible assumptions: the “harvest area” for liquid contribution to a specific bridge is givenby the surface of a spherical cap near the contact spot; and the liquid bridge ruptures at its thinnest portion of the profile, thus redistributing the two “halves” of the bridge upon rupture.Figure optionsDownload full-size imageDownload as PowerPoint slide