Laboratory experimental research on waterflooding sweep efficiency of large-scale and two-dimensional inter-layer heterogeneous physical model

In order to recognize the dynamic sweep process of heterogeneous reservoir in water injection development, a large-scale, two-dimensional heterogeneous physical model was made for the first time on the basis of Zhongyuan Oil Field. Through the three-dimensional physical simulation experiment in laboratory, the quantitative research on the variation characteristics of oil saturation and sweep efficiency of the geological model of positive rhythm and high water-cut reservoir under different injection volume and displacement pressure was made. The results showed that there were obvious differences among the three layers’ producing degree of the heterogeneity model and there was a positive correlation between producing degree and reservoir permeability. When the injection volume was raised from 0.10 HCPV to 1.15 HCPV, the sweep efficiency increased from 36.73% to 100% in high permeability layer, from 24.49% to 76.60% in middle permeability layer, and from 14.24% to 44.90% in low permeability layer. When the displacement pressure difference was raised, the recovery percentage of low permeability layer was significantly higher than that of high permeability. Through hierarchical ordering measures, the recovery percentage of middle permeability layer and low permeability layer can be increased, and the interlayer adjustment is an effective measure for improving the development result of heterogeneous reservoir.