Comparison of lattice and pseudo 3D numerical simulation of tip screen out operation

Abstract

Hydraulic fracturing (HF) is a commonly used technique to stimulate low permeability formations such as shale plays and tight formations. However, this method of well stimulation has also been used in high permeable unconsolidated sandstone formations to bypass near-wellbore formation damage and prevent sand production at some distance apart from the wellbore wall. The treatment is called frac-pack completion, where a short length but wide width fracture is formed by injecting aggressive concentrations of proppant into the fracture plane. This operation is known as tip screen-out (TSO). Detailed design of fluid and proppant, including an optimal pump schedule, is required to achieve satisfactory TSO. In this study, we first assess the lattice-based numerical method's capabilities for simulating hydraulic fracturing propagation in elastoplastic formation. The results will be compared with the same case simulation results using a pseudo 3D (P3D) model and analytical model. Second, we explore the Nolte (1986) design for frac-pack and TSO treatment using lattice-based software and the P3D model. The results showed that both models could simulate the hydraulic fracturing propagation in soft formation and TSO operation, while some differences were observed in generated geometry, the tip screenout time and net pressure profiles. The results are presented. It was noted that fracture propagation regime (viscosity/toughness), nonlocality and nonlinearity had an influence on the different geometries. The advantages of each model will be discussed.

Keywords

• Frac-pack
• Tip screen-out
• Lattice
• Pseudo 3D
• Proppant
• Pump schedule