致密油起伏水平井多段裂缝非均匀流入规律研究  

Research on non-uniform inflow pattern of multistage fractured undulating horizontal wells in tight oil reservoirs

作　　者：魏杰 李小雪 崔旭瑶 王倩[1] 孙渡 李欣 WEI Jie;LI Xiaoxue;CUI Xuyao;WANG Qian;SUN Du;LI Xin(Western Development Office,Research Institute of Petroleum Exploration and Development of Sinopec Group Shengli Oilfield Company,Shandong Dongying 257100,China)

机构地区：[1]中国石化胜利油田分公司勘探开发研究院西部开发室,山东东营257100

出　　处：《非常规油气》2024年第4期97-105,共9页Unconventional Oil & Gas

基　　金：国家自然基金青年基金项目“致密油储层压裂后渗吸动用程度微观控制机理研究”(52204059)。

摘　　要：裂缝走向和水平井轨迹对致密油产能影响较大。为揭示井眼轨迹起伏和水力裂缝形态对致密油产能的影响机理,建立了1套考虑水平段起伏压裂的水平井产能模型。分别建立起伏井眼轨迹多段井模型和致密油藏非达西渗流模型,通过MRST顺序隐式耦合框架实现了井筒流动与储层渗流的耦合,采用Newton-Raphson方法迭代求解产能的计算。基于该模型,开展了起伏水平井非均匀流入规律研究,结果表明:1)非对称裂缝的渗流阶段越早进入径向流,改造区内的流体流动越不充分;2)裂缝偏转时,流体渗流阶段转换差异随偏转角度增大而增加,尤其当偏转角度增大至75°~90°时,早期径向流会逐渐消失;3)当井的曲率小于井长时,井产能较大,而当曲率半径大于4倍的井弦长时,产能显著减少。以上针对起伏水平井非均匀流入规律的成果认识对致密油开采过程中的井轨迹设计以及压裂设计具有重要的指导意义。The influence of fracture orientation and horizontal well trajectory on productivity is significant.To deeply understand the impact of wellbore trajectory undulations and the varied morphology of artificial fractures on the productivity of fractured horizontal wells in tight oil reservoirs,a set of productivity prediction models for multi-fractured undulating horizontal wells in tight oil reservoirs was established.Models for multi-segment wells with undulating trajectories and non-Darcy flow in tight oil reservoirs were constructed,respectively.The coupling of wellbore flow and reservoir seepage was realized through the MRST sequential implicit coupling framework,and the productivity calculations were iteratively solved using the Newton-Raphson method.Based on this model,studies on the uneven inflow patterns of undulating horizontal wells were conducted,showing that:1)The earlier the non-symmetrical fractures enter the radial flow stage,the less sufficient the fluid flow within the reformed area;2)As the fracture deviation angle increases,the difference in the phase transition of fluid seepage increases,especially when the deviation angle increases to between 75°and 90°,the early radial flow gradually disappears;3)When the well’s curvature is less than its length,the well’s productivity is higher,and when the radius of curvature is greater than four times the chord length of the well,productivity significantly decreases.The findings on the uneven inflow patterns of undulating horizontal wells have important implications for well trajectory design and fracturing design in the extraction of tight oil.

关 键 词：起伏井筒 致密油藏 多段压裂 产能模拟 

分 类 号：TE355[石油与天然气工程—油气田开发工程]