均质底水油藏水平井水淹特征研究

Study on Water Flooding Feature in Horizontal Well with Homogeneous Bottom Water Reservoir

利用三维可视化物理模拟装置模拟水平井在均质底水油藏中的水淹规律及水淹动态,并基于渗流力学理论推导了水平井开发见水模式。研究结果表明,在不考虑水平井井筒压降损失的情况下,裸眼或射孔完井水平井的临界见水点位置在水平段中间部位;水平井水淹动态模式为"均匀抬升—中部见水—两边扩展—全井水淹—两翼抬升";在高含水时期水平井通过关井压水锥,可以提高产油速度,降低含水率;相同水平段长度条件下,随生产压差的增大,水平井见水时间提前,产油速度变大,无水期采油量减少,含水上升速度变快。因此,在单井经济极限产量许可下,水平井开发底水油藏应尽量采用较小的生产压差。

By using the 3D visible physical simulation model,in-house physical simulation experiments of the water flooding rule and the water flooding pattern of the bottom water drive reservoir exploited by horizontal well was completed,as well as the breakthrough place of the horizontal well during development was deduced by percolation mechanics theory. Research indicates that in homogeneous bottom water reservoir,without consideration of the pressure drop in horizontal well bore,the critical breakthrough point is in the middle part of the horizontal well under the condition of open hole completion or perforation completion; the dynamic modeling of horizontal well water flooding in bottom water drive reservoir is ＂uniform rising — breakthrough in the middle — extention to both sides— full hole water flooding — double wing rising＂; when the well is high water cut,carrying out shutting the well to control the water coining can increase oil productivity and reduce water cut; under the same length of horizontal parts and accreting producing pressure drop,the breakthrough time is advanced,and the oil-producing velocity increases while the oil production decreases,the ascending velocity of water content is faster as well. In a conclusion,within the single well economic limit production,there should be as little producing pressure drop as possible.