Variation of focusing patterns of laterally migrating particles in a square-tube flow due to non-Newtonian elastic force

Pressure-driven flow experiments demonstrate that spherical particles in dilute polymer solutions are focused on the midline and/or the diagonal in the channel cross-section, with details set by the polymer concentration. Numerical simulations based on the FENE-P constitutive model are then used to understand the variation of the focusing position as a function of the Weissenberg number.