变形三重介质低渗透油藏产能分析

摘要

A numerical simulation program has been developed based on the seepage model of low permeability reservoirs with deformed triple medium to predict reservoir productivity by taking account of the influences of threshold pressure gradient, pressure -sensitive effect and skin effect. The variation curves of productivity versus time are plotted by using actual reservoir development parameters , and the effects of various parameters on oil well productivity are analyzed. The results indicate that threshold pressure gradient has substantial negative effect on oil well productivity, while pressure - sensitive effect has little influence; and skin effect can create a pressure buffer zone near wellbore, which can improve productivity without affecting the duration of oil well production at constant pressure. The variation of oil well productivity distinctively features triple medium.%综合考虑启动压力梯度、压敏效应和表皮效应的影响,根据变形三重介质低渗透油藏的渗流模型,开发设计了三重介质油藏产能预测的数值模拟程序；并结合油田开发中油藏参数的实际数据,绘制了产能随时间的变化曲线,分析了各参数对油井产能的影响.分析结果表明:启动压力梯度对油井产能产生较大的负面影响,而压敏效应影响较小；表皮效应会在井筒附近产生一个压力缓冲区,提高产能,但不影响油井定压生产持续的时间；油井产能变化具有鲜明的“三重介质”特点.