COHESIVE ZONE FINITE ELEMENT-BASED MODELING OF HYDRAULIC FRACTURES

Hydraulic fracturing is a powerful technology used to stimulate fluid production from reservoirs.The fully 3-D numerical simulation of the hydraulic fracturing process is of great importance to the effcient application of this technology,but is also a great challenge because of the strong nonlinear coupling between the viscous flow of fluid and fracture propagation.By taking advantage of a cohesive zone method to simulate the fracture process,a finite element model based on the existing pore pressure cohesive finite elements has been established to investigate the propagation of a penny-shaped hydraulic fracture in an infinite elastic medium.The effect of cohesive material parameters and fluid viscosity on the hydraulic fracture behaviour has been investigated.Excellent agreement between the finite element results and analytical solutions for the limiting case where the fracture process is dominated by rock fracture toughness demonstrates the ability of the cohesive zone finite element model in simulating the hydraulic fracture growth for this case.