Numerical approach to hydraulic fracturing in heterogeneous and permeable rocks

Abstract

Circular samples with borehole are numerically loaded under internal hydraulic pressure rising at a constant rate under zero confining pressure to investigate the hydraulic fracture initiation, propagation and breakdown. Both heterogeneity and permeability of the rocks are taken into account in the studies. The simulations are conducted with a flow-coupled Rock Failure Process Analysis code (F-RFPA2D). The modeling results suggest that the fracture initiation and propagation, the roughness of fracture path and the breakdown pressure are influenced considerably by the heterogeneity of the rock. The borehole diameter elongation and the stress field evolution around the fracture tip during the fracture propagation are also found to be informative in interpreting the hydraulic fracturing behavior.