Numerical simulation of formation damage by drilling fluid in low permeability sandstone reservoirs

Abstract Understanding the formation damage surrounding well during drilling operation is key to predict degree and protect in oil/gas reserviors. Based on core drainage results, we obtained an empirical relationship between invasion volume of fluid permeability reduction formation. Furthermore, equation incorporated into a commercial reservior numerical simulation simulator characterize behaviors process. The results show that, although depth low reservoirs short with range 1.7–2.5 m, effect recovery factor significant due narrow seepage area near fracture region. When considering damage, pressure near-fracture region drops sharply, leading three-stage shape distribution curve. In addition, found that high viscosity density oil-based slurry shorter soaking period are conducive decrease operation. This work reveals fundamental mechanisms reservoirs, which theoretical basis formulation fluids optimization parameters.