Pseudo-coupled hydraulic fracturing analysis with displacement discontinuity and finite element methods

Hydraulic fracturing is a widely employed technique in geoengineering. It is the most common stimulation technique to enhance reservoir permeability. Mathematical modeling of hydraulic fracturing must include several coupled processes, leading to complex and computationally expensive solutions, especially in 3D models. This complexity has led researchers to develop computational tools aiming at accuracy and acceptable computational costs. Several coupled and pseudo-coupled hydromechanical schemes have been proposed in association with the Finite Element (FEM) and Boundary Element Methods (BEM). On the other hand, semi-analytical methods apply to specific simple cases and provide approximations to more complex situa-tions. This work proposes using the Displacement Discontinuity Method (DDM) associated with the Finite Element Method to model the hydraulic fracturing process. An explicit two-way pseudo-coupled scheme is developed where the DDM method solves the rock fracturing pro-cess. The FEM simulates fluid migration inside the fracture and the porous media. The results of the KGD problem considering impermeable and permeable conditions show good agreement with the proposed methodology. Finally, the accuracy of 2-D analyses while reducing the computa-tional time suggests extending the FEM-DDM method to three-dimensional problems as a promising alternative to more complex fracture analyses.

Automated summary

Hydraulic fracturing is a commonly used technique for enhancing reservoir permeability. Mathematical modeling of this process can be complex and computationally expensive, especially in 3D models. Researchers have developed computational tools to ensure accuracy and reduce costs. This study proposes a method using the Displacement Discontinuity Method and Finite Element Method to model hydraulic fracturing, and it shows promising results when applied to different conditions. The method's accuracy and reduced computational time make it a potential alternative for more complex fracture analyses.