Hydro-mechanical modeling of hydraulic fracture propagation based on embedded discrete fracture model and extended finite element method

In this study, an efficient hydro-mechanical model of hydraulic fracture propagation is proposed using the embedded discrete fracture model in conjunction with the extended finite element method. Fracture is embedded into a common computational grid for both stress and pressure fields. A hybrid scheme of fixed stress split and Picard iterative method is presented to deal with the hydro-mechanical coupling and fracture propagation. The model is verified against other numerical solution of hydro-mechanical coupling problem and analytical solution of fracture propagation available from literature. Numerical results show that as matrix permeability increases, more fracturing fluid is required to get a desired length of fracture. The effect of Biot's coefficient is similar to that of matrix permeability. Finally, the model is extended to simulate simultaneous propagation of multiple hydraulic fractures. It's interesting to find that the effect of stress shadowing could be weakened by the poroelastic stress when accounting for hydro-mechanical coupling. The study indicates that the hydro-mechanical coupling could have significant influence on hydraulic fracturing, especially for multi-cluster fracturing of horizontal wells.