Hydraulic fracture simulation with hydro-mechanical coupled discretized virtual internal bond

Abstract The discrete virtual internal bond (DVIB) is a newly developed lattice model, which considers material to consist of bond cells. Through DVIB, both the 3D continuous seepage and mechanical process are reduced to the 1D discrete bond problem. The micro bond functions as both the fluid channel and the mechanical connection between particles. With the calibrated micro hydro-mechanical parameters, the DVIB can simulate the seepage and mechanical behaviors accurately based on a common set of lattice. To model the fractured medium, a fracture is allowed to run through a bond cell, which makes it possible to embed massive fracture into the background meshing scheme. To consider the hydro-mechanical coupling process, the coupling equations are built up, with which the hydro-mechanical coupling process can be well simulated. This method unifies the hydraulic and mechanical process on the micro bond level, providing a micro-macro hydraulic fracture simulation method for the complex reservoir.