Three-dimensional microscale simulation of colloidal particle transport and deposition in model porous media with converging/diverging geometries

摘要

The microscale simulation of colloidal particle transport and deposition in porous media was achieved with a novel colloidal particle tracking model, called 3D-PTPO (Three-Dimensional Particle Tracking model by Python (R) and OpenFOAM (R)), using a Lagrangian method. Simulations were performed by considering the elementary pore structure as a capillary tube with converging/diverging geometries (tapered pipe and venturi tube). The particles are considered as a mass point during transport in the flow and their volume is reconstructed when they are deposited. The main feature of this novel model is to renew the flow field by reconstructing the pore structure by taking the volume of the deposited particles into account. The influence of the particle Peclet number (Pe) and the pore shape on the particle deposition therein is investigated. The results are analyzed in terms of deposition probability and dimensionless surface coverage as a function of the number of injected particles for a vast range of Peclet numbers thus allowing distinguishing the behavior in diffusion dominant and advection dominant regimes. Finally, the maximum dimensionless surface coverage Gfinal/GRSA is studied as a function of Pe. The declining trend observed for high Pe is in good agreement with experimental and simulation results found in the literature.