Multiphysics Coupled Numerical Method for Fluid-Solid-Phase Interaction and Hydraulic Fracturing Simulation

Abstract:

Based on a unified fracture phase-field theory， a fluid-solid-phase multiphysics coupling numerical method is developed and applied to investigate the influence of in-situ stress and natural fractures on hydraulic fracturing and fracture morphology. Numerical simulation studies demonstrate that the fluid-solid-phase coupling numerical method can accurately predict fracture morphologies under tension， shear， and combined tension-shear hydraulic fracturing. The pressure head required to initiate fractures is positively correlated with the in-situ stress level， while the fracture morphology is significantly influenced by the lateral pressure coefficient. Natural fractures alter the distribution of pore pressure， which in turn affects the branching and intersection of hydraulic fractures， leading to diverse fracture morphologies.