Near-wellbore three-dimensional non-planar fracture propagation model

To address the computational challenges of 3D non-planar fracture propagation near the wellbore during hydraulic fracturing, a hybrid numerical model based on the Displacement Discontinuity/Fictitious Stress Method (DDM/FSM) and Finite Volume/Finite Element Method (FVM/FEM) was developed, incorporating a dynamic mesh tracking technique for the fracture front. This 3D non-planar model, constrained by wellbore boundary conditions, was validated for accuracy and reliability, and subsequently used to analyze fracture morphology under stress shadow effects and its key controlling factors. The results indicate that fracture propagation is jointly governed by far-field stress and wellbore-fracture induced stress. Specifically, wellbore-induced stress dominates initiation and reorientation of fractures within three times the wellbore radius, while far-field stress dictates the propagation direction beyond this range. Furthermore, initial fracture dip and fracture number significantly influence morphology: a larger angle between the fracture and the minimum principal stress increases the reorientation distance, whereas a higher number of initial fractures intensify differential propagation and localized reorientation behavior.