Abstract:

It is a key point of high-precision numerical simulation in fractured reservoir to transfer grid unit with both stress field simulation and reservoir numerical simulation.This article holds up two methods of transfer of grid unit, which are vertex corresponding way and section center corresponding way,and analyses their advantages and disadvantages.Vertex corresponding way that have high calculated precision and the simple calculated method,it has aneffect on some functions of stress field simulation and is fit for more calculations to grid unit.Section center corresponding way is in favor of  some especial function of stress field simulation,its calculated method is complex, but its calculated precision infer to vertex corresponding way,so it is fit for less calculation to grid unit.Sha-3 member in the Shi-100 area is a pool with fractured sandstone reservoir.Based on identifying fissures,quantitative relation between stress and fissure parameter was established.Using the vertex corresponding way,80,000 grid units with numerical simulation result were converted to finite element grid units,and then paleostructure stress field which was formed at fissure developing phase was simulated and its result was shown.At last, reservoir parameters of low permeability sandstone,such as porosity and permeability, were got by using the present ground stress simulation, this method will make base for this type of reservoir numerical simulation.

Key words: grid unit, reservoir numerical simulation, stress field, fractured reservoir