抄録
In this paper an improved three-dimensional simulation model (FRACSIM-3D) is presented. It incorporates the mechanical rock-fluid interaction during hydraulic stimulation in more rigorous way than the existing two-dimensional model FRACSIM-2D and quantitatively predicts the 3D reservoir growth behavior. In this model the pre-existing fractures are generated stochastically. The fractal size distribution of the penny-shaped fractures with random orientation is assumed. The fluid flow through the discrete fracture network is simulated by mapping the connectivity of the fractured rock to a regular cubic grid under condition of constant injection pressure. The fluid flow is approximated by the Darcy law equation. Pressure distribution within the fractured rock is used for calculating the growth of the cracks apertures and shear displacements. This requires several iterations; solving the complete flow model simulating the fracture system anew each time and recalculating the shear displacement using the inner fracture pressure from the previous iteration. The results of this numerical solution for hydraulic stimulation are in good agreement with the existing field data collected at the Hijiori hot-dry-rock (HDR) reservoir.
