Shear-induced particle migration in three-dimensional bifurcation channel

• CFD simulations of particle migration in 3D bifurcation channels were performed.
• Diffusive flux model was used for the shear induced particle migration.
• Velocity, concentration and wall shear stress fields were analyzed.
• Effect of bifurcation angle, and bulk inlet concentration were studied.

Flow of concentrated suspension through bifurcation channels are commonly encountered in industrial and biological applications. Shear-induced particle migration in simple and unidirectional geometries like straight channels and tubes have received wide attention but there are very few studies on complex geometries and channels with bifurcations. In this work we report numerical simulation of shear-induced particle migration during low Reynolds number transport of concentrated suspension through Y-shaped three-dimensional bifurcation channel. The effect of bifurcation angle and bulk particle concentration on the velocity, concentration profiles and wall shear stress in the upstream and downstream of bifurcation was studied. It was observed that the velocity profile in the case of concentrated suspension differs significantly from that of Newtonian fluid of same effective viscosity. Near the junction the velocity profile for suspension flow is blunted and the degree of bluntness increases with increase in particle concentration and bifurcation angle. The velocity and concentration profiles in the lateral and span-wise directions of the inlet branch remains symmetric but significant asymmetry was observed in the daughter branches. The locations of the peak velocity and concentration in the inlet and side branch were found to be strongly influenced by the bulk particle concentration and angle of bifurcation. Wall shear stress level was found to be the highest near the bifurcation region.