Fine migration is recognised as a source of permeability reduction in early stages of water flooding and during production operation in consolidated and unconsolidated formations. It causes permeability reduction and reduces the production rate. It is important to recognise this process and the parameters that affect it; it has been the subject of many researches. In this study, a formation damage modelling is developed. For the first time, it considers the effects of changing capillary pressure and relative permeability during formation damage, multilayer retained particles, dispersion and non-Darcy flow simultaneously. A finite difference method is adapted and a new mathematical procedure is used for considering unsteady state particle transport while taking into account the multilayer deposition effect due to particle-particle interaction. Numerical results reveal the significance of the aforementioned effects on the migration, deposition of fines and consequently on the permeability impairment in porous media. Simulation results indicate that when capillary pressure and relative permeability effects are considered in the modelling, permeability reduction is decreased.
Keywords: formation damage, permeability impairment, non-Darcy flow; retain particles, multiphase flow