【摘要】 利用近场动力学方法便于处理多裂纹萌生、扩展和分叉的优点,将其应用于页岩水力压裂过程的数值模拟.结合页岩水力压裂机理提出在近场动力学中由破坏度跟踪裂纹扩展路径,并通过在新生成裂纹面法线方向施加水压载荷的裂纹追踪方法,成功模拟单射孔横剖面开裂水压实验以及单射孔和多射孔水平井纵剖面的水力压裂过程,得到压裂导致的裂纹缝网结构.数值结果还表明初始射孔裂纹会显著影响后续的水力压裂过程.更多还原

【Abstract】 Due to the advantages of peridynamics method in dealing with the initiation,propagation and branching of multiple cracks,it is introduced into the numerical simulation on the hydraulic facture process of shale. Combining with the hydraulic fracture mechanism,a method for tracing crack path according to damage degree in peridynamics is proposed in which the hydraulic pressure is applied in the normal direction of the newly generated crack surface. The cracking pressure of single horizontal well in cross section and the hydraulic fracture of the horizontal well with single and multiple perforations in longitudinal section are successfully simulated by the method. The crack net due to fracturing is obtained. The numerical results also show that the initial perforations have significant effect in the subsequent hydraulic fracture process.更多还原