  We study the transport of inertial particles in water flow in porous media.
Our interest lies in understanding the accumulation of particles including the
possibility of clogging. We propose that accumulation can be a result of
hydrodynamic effects: the tortuous paths of the porous medium generate regions
of dominating strain/vorticity, which favour the accumulation/dispersion of the
inertial particles. Numerical simulations show that essentially two
accumulation regimes are identified: for low and for high flow velocities. When
particles accumulate in high-velocity regions, at the entrance of a pore
throat, a clog is formed. The formation of a clog significantly modifies the
flow, as the partial blockage of the pore causes a local redistribution of
pressure. This redistribution can divert the upstream water flow into
neighbouring pores. Moreover, we show that accumulation in high velocity
regions occurs in heterogeneous media, but not in homogeneous media, where we
refer to homogeneity with respect to the distribution of the pore throat
diameters.
