Lattice Boltzmann simulation of shear viscosity of suspensions containing porous particles

We present three-dimensional lattice Boltzmann simulations of dilute suspensions containing porous particles. The fluid flow around and inside a porous particle is described by the volume-averaged macroscopic equations in terms of intrinsic phase average. The energy dissipation of the suspended particle in a Couette flow is calculated to obtain the relative viscosity of the suspension. Results show that the relative viscosity of the suspension increases linearly with the particle volume fraction. A correlation equation is obtained for the intrinsic viscosity as a function of Darcy number. It is found that when the suspension is at the inertial flow regime, its intrinsic viscosity increases linearly with Reynolds number, and the increasing rate depends on Darcy number.