Numerical simulation study on three-dimensional fracture propagation of synchronous fracturing

A new three-dimensional fluid-solid coupling fracture propagation model of synchronous fracturing was established to study the dynamic propagation process of simultaneous hydraulic fracturing. In this paper, we used an improved three-dimensional boundary element method and a finite difference method, respectively, for calculating the deformation of the reservoir rock and the flow of the fracturing fluid during the fracturing process. The interaction between hydraulic fractures and nature fractures was also considered. Sensitivity analysis showed that during synchronous fracturing, the fractures between the wells attracted each other and injected with more fluid due to interference between the fractures. Affected by natural fractures, the trajectory of hydraulic fractures was more tortuous. Besides, the width and height of hydraulic fractures captured by natural fractures were reduced. In order to reduce the difference in length between individual fractures, smaller well spacing and larger cluster spacing should be used.