Numerical Simulations of the Hydraulic Fracture Propagation in Poroelastic Media Using the Coupled Hydro-Mechanical Field-Enriched Finite Element Method

In this paper, a coupled hydro-mechanical field-enriched finite element method (HM-FE-FEM) is proposed to simulate hydraulic fracture propagation in poroelastic media. The governing equations of fluid flow and displacement are established based on the field variable and Biot's poroelastic theory. The unified field variable is introduced to characterize cracks and seepage channels in the poroelastic media. The coupled hydro-mechanical problems are solved by the staggered iterative scheme based on the Newton–Raphson iterative algorithm. The proposed method can be used to predict fluid pressure, fracture opening distribution, as well as crack initiation and propagation in hydraulic fracturing engineering. The accuracy and correctness of the proposed method HM-FE-FEM are validated by four benchmark examples. Subsequently, two classical hydraulic fracturing cases are investigated to showcase the potential and versatility of the proposed method. Finally, the performance of the proposed method is demonstrated by simulating hydraulically induced crack propagation in different types of complex natural networks. All the numerical results demonstrate the capability of HM-FE-FEM to predict and handle complex intersection behaviors in hydraulic fracturing engineering.