Numerical modelling of non-Newtonian slurry in a mechanical flotation cell

This paper investigates the formation of a cavern around the impeller of a mechanical flotation cell agitating a highly non-Newtonian mineral slurry. Caverns consist of yielded fluid surrounded by stagnant fluid and are known to form in non-Newtonian yield-stress fluids. Two single phase non-Newtonian fluids were modelled with rheologies equal to experimentally determined mineral slurries, using the Herschel-Bulkley non-Newtonian model. Findings showed a cavern forms around the stator, with its size depending on slurry yield stress, and that the Shear-Stress Transport (SST) k − ω turbulence model predicted the cavern most accurately.

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