Simulation of particle settling in rotating and non-rotating flows of non-Newtonian fluids

Finite element solutions are presented for the flow of Newtonian and non-Newtonian fluids around a sphere falling along the centreline of a cylindrical tube. Both rotating and stationary tube scenarios are considered. Calculations are reported for three different inelastic constitutive models that manifest shear-thinning, extension-thickening and their combination. The influence of inertia and these various forms of viscous response are examined for their influence upon the drag on the settling particle and the structure of the flow. Simulations are performed by employing a semi-implicit time marching Taylor-Galerkin/pressure-correction finite element algorithm, a fractional-staged scheme of second-order-accuracy. (C) 1998 John Wiley & Sons, Ltd.