Peridynamic Modeling of Hydraulic Fracture in Poroelastic Media with Leak-Off
摘要
Hydraulic fracturing is widely employed in engineering practice such as shale gas exploration and enhanced geothermal systems, where the porous solid is fractured by fluid injection. The leak-off, which refers to the loss of fracturing fluid into the surrounding porous solid, is known to affect the fracking efficiency. This work introduces a new peridynamics-based computational approach to model hydraulic fracturing in porous media. The model integrates a semi-Lagrangian peridynamics (PD) formulation for simulating free-flowing fluids and a poroelastic PD formulation to capture the deformation and fracturing of porous solids with porous flow. The fluid-solid interaction (FSI) is modeled by coupling the two PD formulations, accounting for hydraulic forces on fracture surfaces and fluid leak-off into the porous medium. The model is benchmarked with 1D consolidation problem, demonstrating its ability to capture pore pressure dissipation under external load. Simulation for hydraulic fracturing in porous media with comparison to the analytical solution of the Kristianovich-Geertsma-de Klerk (KGD) model is presented, to demonstrate the potential of the proposed method in predicting hydraulic fracture propagation in porous media.