Modeling hydraulic fractures propagation considering changing in the primary energy loss mechanism

Accurate modeling of the hydraulic fracturing treatment is important to design a successful treatment and prevent screenout. An innovative numerical method is presented, here, for modeling fluid-driven fractures propagation considering changing in the primary energy loss mechanism during propagation. The proposed method is based on the extended finite element methods with modifications to incorporate variable stress singularity at the crack tips for the transition between toughness-dominated and viscosity-dominated regimes. Moreover, a consistent enriched function is introduced for fluid pressure calculations close to the fracture tips to catch its singularity. The numerical results were validated against the analytical solutions for two extreme hydraulic fracture propagation regimes. Mesh independency and convergence rate of the proposed method are verified. Comparison between fracture volumes assuming changing in the primary energy loss mechanism and constant primary energy loss mechanism during hydraulic fracture propagation is provided.