3D DEM Simulation on the Interference of Multiple Hydraulic Fractures in Horizontal Wells

摘要

In this study, a 3D DEM lattice simulator is utilized to model the simultaneous growth and mechanical interference among members of an array of hydraulic fractures along a horizontal well. The deformation and fracturing of the rock matrix are simulated by the lattice. Fluid flow is implemented within the fractures and fully coupled with the mechanical deformation. Simulation results demonstrate non-planar fracture propagation behaviors induced by the stress shadowing effect in a full 3D setting without restriction on the fracture trajectory. Indeed, the simulation shows one fracture can be dominant in growth due to local heterogeneity and take in most of the fluid flow. The simulation also captures complex fracture front segmentation and asymmetric growth both in length and height under the combined impact of stress shadowing effect and perforation/in-situ stress misalignment, which could not be explicitly considered in previous pseudo-3D or parallel-planar 3D models.