Boundary Study of the F low of the Concentrated S uspensions

1. Boundary Study of the Flow of the Concentrated Suspensions P. Mirbod, J. Koplik, & J. Morris- City College of New York Abrasive wear induced by the slow flow of concentrated slurry is encountered in many industrial problems. In this work, using a combination of experiment and theory, the coupled issues of the rheology of a concentrated solids-laden liquid and the boundary wear generated as it flows in confined domain in the geometry of simple shear are demonstrated. An experiment is performed with different abrasive particles, specimen materials and under different test conditions such as abrasive concentration and angular velocity. Using the von Mises yield criterion the load at which the plastic yield begins and boundary wear becomes observable is determined. In order to reveal the morphology of the surface, scanning electron microscopy (SEM) were used. Schematic of the experimental device Morphology of the paraffin wax work-piece under abrasive particles, PMMA(200 μm diameter) in density matched fluid, ϕ=40% & γ=6 s-1,γ=12 s-1,γ=23 s-1, t=5 min. The scale bar indicates 300 microns. Acknowledgments: Supported by NSF PREM DMR # 0934206