Calculation Method for Equivalent Geometric Characteristics of Hydraulic Fractures in Heterogeneous Rock Based on PHF-LSM Method

The permeability-based hydraulic fracture-level set method (PHF-LSM) is a smeared fracture model based on Biot consolidation theory. The model simulates the fracture development process by weakening the fracture and rock material properties in the damaged area, so the geometric characteristics of hydraulic fractures cannot be given in the solution process. According to the average effective stress field distribution during hydraulic fracture propagation, the equivalent path and equivalent height of hydraulic fracture by PHF-LSM method are established in this paper. According to the displacement field around the equivalent propagation path, the equivalent opening of hydraulic fractures is calculated, and the effectiveness of the proposed method is verified by comparing with KGD theoretical model. At the same time, the dynamic development characteristics of equivalent geometric characteristics for fractures in both homogeneous and heterogeneous rock are calculated. The results demonstrate that the established equivalent calculation method compensates for the deficiency of PHF-LSM by allowing for the determination of geometric characteristics of hydraulic fractures.