Phase-Field Modeling of Hydraulic Fracturing Under Heterogeneities And/Or Layering of Rock Properties and In-Situ Stress

摘要: ABSTRACT Hydraulic fracturing is a process of creating artificial fractures to enhance the hydraulic conductivity of nearly impermeable rock masses, enabling an economic development of many subsurface energy systems. Due to heterogeneities and layering of rock properties and in-situ stress, hydraulic fracture propagation commonly involves highly complex patterns. To investigate the effects of material heterogeneities and layered rock structure on hydraulic fracturing, numerical modeling usually plays a central role. Most existing numerical methods, however, face a formidable challenge in handling fracture propagation with complex geometries, which can potentially occur in heterogeneous and layered rock formations. A remedy for this challenge is to use the phase-field method. Basically, the phase-field method models the fracture propagation as evolution of a diffusely distributed damage variable …