Numerical study on competitive propagation of multi-perforation fractures considering full hydro-mechanical coupling in fracture-pore dual systems

Abstract

Hydraulic fractures initialized from different perforations have different contributions to well production. Therefore, it is essential to study the competitive propagation of hydraulic fractures among multiple perforations. In this study, a fracture-pore flow model coupled with wellbore flow was developed and implemented in a three-dimensional numerical model to simulate multi-perforating hydraulic fracture propagation. The hydro-mechanical coupling effects in fractures and porous media were fully considered. The effectiveness of the model in simulating hydraulic fracture propagation, fracture reorientation and transient fluid leak-off was verified. Finally, a field hydraulic fracturing operation with multi-perforations in a tight reservoir was simulated. The sensitivities to the reservoir heterogeneity, fluid leak-off, layer inclination, well deviation and perforation friction were investigated in detail. This study revealed the following: 1) layered heterogeneities can cause strong competitive propagation of multi-cluster fractures; 2) flow rate in each perforation is controlled by perforation friction and stress shadow; 3) reservoir heterogeneity, layer inclination, and well deviation are major factors of the asymmetric fracture propagation; 4) the well deviation toward the direction of the minimum horizontal stress causes an asymmetric stress shadow and reduces the effective spacing of the perforations.