Notch Driven Hydraulic Fracturing in Open Hole Completions: Numerical Simulations of Lab Experiments

Hydraulic fracturing is the principal stimulation technique used to improve the oil and gas recovery and enhance production from unconventional resources. In open hole completion, the direction of the initiated hydraulic fracture around the wellbore is mostly influenced by existence of natural fractures or rock inhomogeneity. After passing the stress perturbed zone near wellbore, the fracture will propagate perpendicular to the minimum principal stress direction. The fracture turning and tortuosity around the wellbore significantly increases the pressure drop and difficulty in placement of proppant. The use of a notch, as a predefined crack in the preferred fracture propagation direction is commonly done in lab experimental studies to assist the fracture to initiate more easily and direct the fracture propagation near wellbore. The use of notch in field hydraulic fracturing applications has also been reported. In this study we numerically simulate the impact of the notch geometry on fracture initiation and propagation pressure and geometry. The XSite, a lattice based model was used to simulate some lab experimental data and the results showed the importance of notch length and its orientation on fracture propagation.