Numerical simulations of suspensions of rigid spheres in shear-thinning viscoelastic fluids

In multiphase flows, accurately modeling the interaction between the liquid phase of complex fluids and a porous medium of solid spheres poses a fundamental challenge. The dynamics of moderately dense non-colloidal suspensions constituted by static random arrays of mono-disperse spherical particles in non-linear viscoelastic fluids is studied numerically. This numerical study consists of about 9000 different systems, in which the volume fraction phi (0.04 < phi < 0.2) of the dispersed solid phase, the Reynolds number Re (5 < Re < 50), the solvent viscosity ratio beta (0.05 <= beta <= 0.9), the Weissenberg number Wi (0.5 <= Wi <= 4), and the mobility parameter of the Giesekus model alpha (0.1 <= alpha <= 0.5) were varied to understand the particle's interactions with the viscoelastic suspending fluid. We aim to investigate the relationship between the volume fraction of the dispersed solid phase and the non-linear rheology of shear-thinning viscoelastic fluids with the normalized average drag force < F >. In addition, by assessing the flow patterns predicted numerically, we were able to provide a characterization of the velocity and stress fields as a function of the simulation parameters.