Dissolved Gas Reservoir Fracturing Wells Dynamic Simulation Of Three-dimensional Three-phase Study

Hydraulic fracturing, which has been being widely used in low permeability oil & gas field all over the world, is an important stimulation technique for the reservoir exploration and exploitation and it is necessary to predict the post-frac production performance for the design optimization prior to the fracturing. In recent years, with the increasing applications in kinds of reservoirs, to correctly predict the post-frac production performance of the dissolved-gas pool is exigent and need to be further studied. Aiming at this subjected, the author particularly lucubrated in this paper based on the numerical simulation and following achievements are obtained:(1) Based on the fluid percolation mechanism, Darcy's Law and material balance principle, a mathematic model of 3-D and 3-phase percolation for the fractured well of dissolved-gas pool, with all things considered, is established. It is of great applicability and offers a theoretical basis for the prediction of post-frac production performance.(2) Being the numerical theory of the 3-D and 3-phase prediction model, corresponding calculation model is deyeloped. With the alternating implicit method, it is of good convergence and stability.(3) With the introduction of non-Darcy factor, a universal flow equation integrating the non-Darcy flow in fracture with the Darcy flow in reservoir and a new numerical calculation method for non-Darcy factor is put forward. Differing from the constant in the traditional, non-Darcy factors on different positions can be determined along the fracture length, making the performance prediction much more exact and more authentic.(4) Regarding the fracture and the reservoir as an integrated system as well as considering the time-varying effect of fracture conductivity, the grid partition upon matching is studied and it makes the performance computation still more accurate and more reasonable.(5) With Visual Basic 6.0, numerical simulator for the performance prediction model, which is the calculation tool and the most important achievement in this paper, is also developed.(6) Based on the numerical simulator programmed in this paper, the effects of such factors as fracture length and conductivity, in-place permeability, original water saturation, porosity and bottom hole flowing pressure, non-Darcy effect as well as different boundary conditions on production performance including daily production of oil, water and gas is systematically analyzed. As the results suggest, different impacts...