Microhydrodynamics of stirred media milling

Abstract The milling media dynamics on micro-scale is considered. It is assumed that the turbulence energy dissipates due to media–liquid viscous friction, lubrication and partially inelastic collisions of the milling beads with each other. Both the mean velocity of the milling media oscillations and their frequency are estimated. The numerical study of the milling bead dynamics in the mixing tank is performed. The media radial stratification due to the centrifugal force is estimated by a simple model based on equilibrium of the mass fluxes caused by the centrifugal force and the turbulent dispersion.

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