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针对聚合物驱油两相渗流过程中的指进现象，建立了平面可视的渗流实验装置与实验方法和图像及数据处理方法。以驱替的波及面积为主要参数，建立了分维计算方法，并通过不同粘度的驱替液的驱油实验，确证油水两相的驱替渗流过程是分维的，同时得出了分维数是和聚合物驱替液粘度间的函数关系。由五点法井网注采模型上进行的实验现象表明，随着聚合物溶液浓度增加其粘度也增加，驱油时其前缘的推进也愈均匀。定量计算结果表明，随着聚合物溶液粘度增加，分维数也增大。如用不含聚合物的清水驱替时，分维数是１．５６３，当用１５００ｍｇ／Ｌ的聚合物溶液驱替时，分维数是１．７９１；当聚合物浓度为４０００ｍｇ／Ｌ时，分维数增加到１．９５６，且很接近于完全波及时的极限值２．０。这表明：用聚合物溶液驱油，驱替波及过的地方“破碎”程度减小，波及效果增加。这一实验和理论计算结果表明，用聚合物溶液驱油时，在扩大波及系数的同时，还可提高波及效果。从微观上讲，聚合物驱还可以降低残余油饱和度，提高洗油系数，其量和聚合物溶液粘度有关。
Aimed at the phenomenon of fingering in polymer flooding two-phase seepage flow, a plane seeable seepage experiment device, experimental method, image and data processing method are established. Taking the swept area of flooding as the main parameter, a fractal dimension calculation method was established. Through the oil displacement experiment of displacement fluid with different viscosities, it was confirmed that the displacement percolation process of oil-water two-phase was fractal dimension and fractal dimension The number is a function of the viscosity of the polymer flooding fluid. The experiment carried out by the five-point well pattern shows that the viscosity of the polymer solution increases with the concentration of the polymer solution and the propulsion of the leading edge is more uniform. Quantitative calculation results show that, as the viscosity of the polymer solution increases, the fractal dimension also increases. The fractal dimension was 1.563 when flooding with polymer-free water. The fractal dimension was 1.791 when flooding with 1500mg / L polymer solution. When the polymer concentration was 4000mg / L , The fractal dimension increased to 1.956, and it was close to the limit value of 2.0 when it completely spread. This shows that: polymer solution to drive oil, flooding over the place of “broken” to reduce the extent of the wave effect increased. The experimental and theoretical calculations show that polymer flooding, while expanding the sweep coefficient, but also can improve the wave effect. Microscopically, polymer flooding can also reduce residual oil saturation and increase oil wash efficiency, which is related to the viscosity of the polymer solution.