聚合物驱双层油藏试井分析方法

考虑了在地层中聚合物溶液存在剪切、扩散、对流等物化参数作用,建立了双层油藏聚合物驱试井解释模型。采用有限差分算法进行了数值求解,研制了典型曲线图版。研究表明:典型曲线存在4个流动段;当两个层的表皮系数同时增大时,压力导数曲线在径流段重合;当某一个层的表皮系数固定不变,另外一个层的表皮系数增加时,压力导数曲线在径向流段不再重合。随着注入聚合物溶液浓度增大,过渡段的"驼峰"越大,径向流段上翘幅度越大。实例应用表明该模型能准确确定不同地层的渗透率、表皮等参数。

Well Test Analysis Method of Two Layers Reservoir With Polymer Flooding

Considering the polymer solution in the presence of shear, diffusion and convection, well test models of multi-layered reservoirs by polymer flooding was established, and finite difference method was employed to solve the mathematical model for typical curve. It shows that the type curve have four flow sections. With increasing of skin factors of two layers, the pressure derivative curve coincide in radial flow section; when the one of skin factors of a layer is constant, while the other one is increasing, the pressure derivative curve no longer coincide in radial flow section. With increasing of the initial concentration of polymer solution, along with decreasing of the index, the pressure derivative curve move upward obviously. The field-test application indicates this model can accurately evaluate the different formation permeability, skin and other parameters.