In order to improve the accuracy of numerical simulation in Weizhou A low-per-meability reservoirs,this paper conducted in-depth research on oil-water relative permeabil-ity relationship of low-permeability reservoirs based on digital core experiment,improved the numerical simulation software,and formed a remaining oil prediction method considering nonlinear seepage laws.The results show,in the nonlinear seepage stage,the oil-water rela-tive permeability is a function of water saturation and displacement pressure gradient.The farther away from the injection and production well,the lower the displacement pressure gra-dient,and the greater the residual oil saturation in the relative permeability relationship.The median pressure of oil reservoirs in the Weizhou area has significantly increased in low-per-meability reservoirs,indicating that nonlinear flow characteristics are mainly existing in low-permeability reservoirs.Summarize the distribution laws of remaining oil in low-permeability reservoirs under different well networks predicted by numerical simulation,that is,on the main permeability channel of injection and production wells,the displacement pressure gra-dient is high,the remaining oil is not enriched,and away from the main permeability chan-nel,the displacement pressure gradient gradually decreases,which is the main area of re-maining oil enrichment.This method is phased and solves the problem of low remaining oil prediction accuracy caused by traditional methods not considering the nonlinear flow charac-teristics of low-permeability reservoirs.It provides an important foundation for improving re-covery in low-permeability reservoirs.
维普
万方数据