水力射孔参数对油水井压裂影响的数值试验

利用RFPA(Rock Fracture Process Analysis)软件,数值计算了不同水力射孔参数及地应力等条件下的孔眼直径、射孔深度、射孔孔眼轴线与最大水平应力夹角、压裂液加载速度、模型尺寸、地层起裂压力以及裂缝二维扩展情况,计算过程中模拟的岩样物性基本保持不变。计算结果发现,增加射孔直径、深度可以显著降低起裂压力;沿最大水平应力方向射孔起裂压力最低;存在一个最优的压裂液加载速度。这些计算结果可为油水井的压裂设计提供参考。

Numerical test to the influence of hydraulic perforation parameter on fracture in oil and water wells

The perforation diameter, its depth, perforation axial line and the included angle of maximum horizontal stress, the loading speed of fracturing fluid, model size, initiation formation pressure and 2 dimensional fracture extension are numerically calculated by using software of rock fracture process analysis (RFPA) under the conditions of different hydraulic perforation parameters and in situ stress. During the calculation the simulated physical properties of rock samples basically remain constant. The result indicates that the initiation fracture pressure can be obviously reduced by raising the perforation diameter and depth; while the initiation perforation pressure is the lowest along the direction of maximum horizontal stress. In addition there exists an optimal loading speed of fracture fluid. The results are used to provide reference for oil and water well design.