鄂尔多斯盆地致密油储层体积压裂改造后,单井产能较常规压裂有了大幅度的提高,但由于地层压力系数小,仅靠天然能量开发效果并不理想,因此,探索体积压裂井的注水补充能量方式有重要意义。基于体积压裂复杂缝网形态的特点,建立了缝网数值模拟模型,对直井体积压裂缝网渗流特征进行了分析;以体积压裂矩形井网为例,研究了注采形式下体积压裂井的增产机理,并结合并网对缝网适配性进行了探索。研究结果表明,缝网系统增加了储层垂向动用程度,提高了主裂缝壁面方向的水驱波及体积,改善了注采井间的水驱动用效果。由于缝网系统存在"最短渗流距离",体积压裂井见水后含水上升较快。通过长庆某典型致密油储层直井体积压裂实例分析,对后期可行的井网形式进行了优化设计和论证。
The single well productivity of network fractured well can increase tremendously than that of conventional fractured well in tight oil reservoirs in Ordos Basin.However,due to the low pressure coefficient,the development efficiency depending on natural energy is not very good.Therefore,exploration on water flooding network fractured well is of significance.Based on the characteristics of complex fracture network,the fracture network numerical simulation model is established to analyze the fluid flow features in vertical network fractured well.Taking rectangular well pattern as example,stimulation mechanism for vertical network fractured well is studied on the condition of water flooding well pattern,and the water flooding suitability is explored.Results demonstrate that fracture network increases the degree of producing reserves,enlarges the sweep volume on the side of vertical wall of fractures and improves the sweep efficiency between injection and production well.Due to the "shortest flowing distance",production well’s water cut increasing rate in fracture network increases fast after water breakthrough.Case analysis is made on the vertical network fractured well in typical tight oil reservoir of Changqing oilfield.Furthermore,the optimized well pattern for network fractured water flooding is designed and discussed.