EXPERIMENT STUDY ON HETEROGENEITY LINEAR MODEL OF WATER DRIVING OIL

In order to determine the impact of different combined core mode,percolation matter,permeability,heterogeneity on water flooding efficiency and distribution of remaining oil,and to do further research,this dissertation firstly selects different natural cores,uses combined core technique,and establishes different heterogeneous models.Then with the help of combined physical simulation technique and constant flow rate method,water driving oil experiment is done.From the experiment,the following findings are acquired:as series connection model is one-way percolating,water flooding efficiency at inlet is obviously higher than that at outlet,saturation of remaining oil at outlet is obviously higher than that at inlet,and water flooding efficiency and saturation of remaining oil has nothing to do with the value of permeability;the distribution of remaining oil is even in the low-medium-high model,whereas it is centralized in the low permeability core in the high-medium-low model;the water flooding efficiency of the combined model has connection with the equivalent permeability and heterogeneity.As vertical heterogeneous model is water flooding,the remaining oil is centralized in the least permeability core.Finally,it is concluded that in the formation characterized by obvious horizontal heterogeneity character,the project of water flooding in high permeability zone and oil extraction at low permeability zone can be adopted to improve the recovery ratio. And in the formation characterized by obvious vertical heterogeneity character, the projects of chemical water plugging by profile control,plugging the high permeability formation,improving water entry profile,or separate water injection can be adopted to improve the recovery ratio.