Study on multi-fracture propagation based on the uniform coefficient of fracture propagation

Abstract

Multi-cluster fracturing is one of the most critical technologies for the efficient exploitation of unconventional reservoirs, and fracture uniform propagation during synchronous multi-fracture propagation is the goal of hydraulic fracturing. Most of the current studies on the simultaneous propagation of multiple fractures characterize the degree of uniform fracture propagation by the difference in fracture length or width, while the uniformity of multiple fractures is affected by multiple fracture parameters simultaneously, which makes such a characterization method biased. In this article, the stress interference of multiple fractures, fluid flow in fractures, flow distribution, and fracturing fluid filtration are comprehensively considered to establish the synchronous propagation model of multiple fractures in horizontal wells, and the fracture propagation patterns are simulated for different parameters. Then, the propagation uniformity coefficient of multiple fractures is proposed to represent the propagation uniformity of multiple fractures. The fracture uniformity coefficient is the result of the combination of fracture length, fracture width, inlet volume and fracture deflection angle, which can more comprehensively represent the uniformity of fracture propagation. Based on the uniformity coefficient of multi-fracture propagation, the law of multi-fracture interference is studied, and the parameters of multi-fracture propagation are optimized combining with an engineering background.