Numerical simulation and measurement of liquid hold-up in biporous media containing discrete stagnant zones

We have studied hydrodynamic dispersion in single-phase incompressible liquid flow through a fixed bed made of spherical, permeable (porous) particles. The observed behaviour was contrasted with the corresponding fluid dynamics in a random packingof impermeable (non-porous) spheres with an interparticle void fraction of 0.37.Experimental data were obtained in the laminar flow regime by pulsed - eld gradient nuclear magnetic resonance and were complemented by numerical simulations employing a hierarchical transport model with a discrete (lattice Boltzmann) interparticle flow field. Finite-size effects in the simulation associated with the spatialdiscretization of support particles or dimension and boundaries of the bed were minimized and the simulation results are in reasonable agreement with experiment.