Research On Predominant Flow Field And Residual Oil Distribution Considering Gravity Effect

The basic idea of streamline numerical simulation technique is to decompose the 3D problem into a series of 1D problem along streamlines. Fluids move along the natural streamline grids. Meanwhile, simulation accuracy is increased by maintaining the sharp flood fronts from the displacement processes and reducing grids orientation effect. On the basis of small black oil model, the two phase oil/water streamline model with gravity and capillarity effect is established and solved numerically. Through optimization of streamline generation and solution methods, an integrated kit of streamline-based numerical simulation software is developed. The reliability and accuracy of the software is tested through comparison with conventional numerical simulation software.On the basis of this software kit, the paper establishes theory of reservoir flow field, analyzes performance and static factors that affect reservoir flow field distribution, chooses water crossing multiple, flow velocity and water cut as performance factors, adopts analytical hierarchy process and fuzzy mathematics to get a performance appraisement target of flow field, establishes the grade scale of flow field and shows it in 3D visual module. Additionally, through field data in Dagang Oilfield, the reliability and accuracy are tested again. According to the result of simulation, most static factors are statistically analyzed and overall appraisement target is achieved. Lastly, research on the relationship between predominant flow field and residual oil distribution from horizontal, vertical and 3D perspectives is done. Meanwhile, some suggestions about residual oil production are promoted.