The Density Ratio Effects on the Motion of a Three-Dimensional Drop in Poiseuille Flow at Finite Reynolds Numbers

The density ratio effects on the motion of a three-dimensional drop in Poiseuille flow are examined at finite Reynolds numbers using a finite difference front tracking method. The elliptic pressure equation is solved by a multi-grid method. For deformable drops, the wall repulsion increases and this effect moves the equilibrium position closer to the centerline of the channel. Results show that all drops with deferent density ratios migrate to an equilibrium position about halfway between the centerline and the wall. The drops move to an equilibrium position closer to the wall with increasing the density ratio. The axial velocities of the drops increase with decreasing the density ratio, because the drop with smaller density ratio moves to a lower final position. Also, the deformation of the drops is the same after an initial transient period. During the initial transient period, the deformation increases as the density ratio increases.