Shear-induced migration of concentrated suspension through Y-shaped bifurcation channels

Abstract

ABSTRACTTransport of suspension through bifurcation channels has many scientific and engineering applications, particularly in industrial and biological processes. At moderate concentrations, the shear-induced migration of particles in pressure-driven channel flow causes nonuniform concentration profile. The velocity profile also shows significant deviation from the Newtonian fluid behavior. The phenomenon of shear-induced migration has been well studied for straight channels and tubes, but there are few studies on channels with bifurcations. We have used the diffusive flux model to study the particle migration during transport of concentrated suspension of neutrally buoyant particles in Y-shaped two-dimensional (2D) bifurcation channels. The governing equations of continuity, momentum, and particle transport were solved to obtain the velocity and particle concentration profiles in the channel. The effect of particle size, bifurcation angle, bulk concentration, and flow rate on the velocity and concentration profile was studied. The velocity profile in the case of concentrated suspension differs significantly from that of Newtonian fluid of the same effective viscosity. Near the bifurcation section, the velocity profile for suspension flow is blunted, and at larger bifurcation angles peak-valley-peak–shaped profile is observed. The velocity and concentration profile in the inlet section remains symmetric, but significant asymmetry is observed in the daughter branches due to shear-induced particle migration.