四注平-直联合开发井网压裂水平井开发规律研究

Research on fractured horizontal well development law of four injection well horizontal-vertical well pattern

为深入研究平-直联合开发井网压裂水平井的开发指标计算与开发规律,结合点源函数建立平-直联合开发压裂水平井的地层压力解公式,追踪生成流线划分流管,基于流管法实现压裂水平井的开发指标计算。给出了平-直联合开发压裂水平井的流线以及压力梯度场图,分析其流线特征以及渗流规律。结合某外围平-直联合开发区块实际情况,以四注井网为例计算了压裂水平井的开发指标,在此基础上分析其开发规律。模拟结果表明:该四注井网产量递减为指数类型,产液量主要分为低含水期下降、中含水期稳定和高含水期回升3个变化阶段,含水上升变化分为低及高含水期采出程度低、中含水期采出程度较高3个阶段。

In order to recognize the development index calculation and development rule of the fractured horizontal well ofhorizontal-vertical well pattern, Green function is used to build the fractured horizontal well formation pressure formula of horizontal-vertical well pattern, then, stream-tube is classified with the help of Euler method, and based on stream-tube method,the development index is calculated. The streamline and pressure gradient field for the fractured horizontal well of horizontalverticalwell pattern are put forward, and the characteristics and the seepage law of the fractured horizontal wells are analyzed.Considering an actual peripheral horizontal-vertical well pattern block, taking four injection well pattern as example, the developmentindex of the fractured horizontal well is calculated, and the development law is analyzed. The simulated results showthat the production decline of the four injection well pattern is of index type, liquid production is mainly divided into threestages which are decline at low water cut stage, being stable at medium water cut stage, and rise at high water cut stage, and the water cut rise is mainly divided into three stages which are low and high water cut stages with low reserve recover degree,and medium water cut stage with high reserve recover degree.