On particle incipient motion from the sedimentation layer in shear flow

Abstract

Abstract This paper presents the results of numerical modelling for a laminar flow around a spherical particle located near a sedimentation layer. The particle being at the minimum distance from the rough layer is affected by a fluid shear flow with Reynolds numbers varying from 2 to 200. The considered fluids included Newtonian and power law ones. Depending on a shear Reynolds number, the critical Shields numbers have been determined to describe the particle’s incipient motion. The obtained parameters have been compared against those for a smooth surface to demonstrate that in some cases the differences in critical stress coefficients may reach up to 70%.