Optimization method of fracture parameters in multistage fracturing of horizontal wells

Analyzing the simultaneous propagation of multiple fractures in horizontal wells is a challenging task. Although many fracture propagation models exist, the primary controlling factors are unclear. A fast and relatively accurate optimization method is urgently needed. In this study, a semi-analytical model of fracture propagation is established that couples stress interaction with fracture propagation using the energy balance principle, which can run a complete simulation process within 10 seconds. The simulation results show that the pumping rate, perforation cluster number, and fracturing fluid viscosity are the primary factors controlling fracture propagation. For two areas with different elastic modulus, the process of parameter optimization is analyzed. The reservoir with an elastic modulus of 10 MPa has an optimal perforation cluster number of 5, while the reservoir with an elastic modulus of 35 MPa has an optimal perforation cluster number of 8. The results show that the area with larger elastic modulus need to set a larger number of clusters, while the area with smaller elastic modulus have a smaller number of perforation clusters. This work aims to provide a practical and simple workflow for optimizing the fracture design of fractured horizontal wells.