Coupled Simulation of Fracture Propagation and Lagrangian Proppant Transport

The distribution of proppant within hydraulic fractures significantly influences fracture conductivity, thus playing an essential role in oil and gas production. Currently, small-scale and static fracture problems have been successfully simulated with high accuracy using Lagrangian proppant transport models. Field-scale problems are often simulated with the mixture model, the accuracy of which still requires improvement. In this work, a novel model that couples fracture propagation and proppant transport using an Eulerian-Lagrangian framework is proposed. The displacement discontinuity method (DDM), the extended Poiseuille’s equation, and the multiphase particle-in-cell (MP-PIC) method are used for fracture deformation and propagation, fluid flow, and proppant transport simulations, respectively. The fluid flow is fully coupled with the fracture equations and then coupled with the Lagrangian proppant model using a two-way coupling strategy. The proposed model is carefully validated against published numerical and experimental results. Then, we use the model to investigate the fracturing process in a layered reservoir. The impacts of fluid leakoff and proppant injection order are discussed. Special phenomena such as proppant bridging and tip screenout are captured. This study provides a novel and reliable way for simulating proppant transport in practical problems, which is of great importance to fracturing designs.