用数值方法研究面积井网系统的扫油效率

本文应用三维三相黑油模型对等厚均质水平地层在不同流度比下,不同注入速度下,对五点系统、七点系统、直线排状系统及交错排状系统的面积扫油效率进行了系统计算。计算结果表明,井网系统不同,同一流度比下,面积波及系数也不同。五点系统最高,依次为交错排状、直线系统和七点系统。在不利流度比下,驱替的不稳定过程对五点和七点系统的波及系数的影响小于对交错排状和直线排状系统。当流度比从0.2增加至10时,波及系数急剧下降。当流度比进一步增大时,其递减速度减缓。见水后继续注水,面积波及系数可继续增大,直至地层全部水浸。在同一流度比下,含水率小于50％时,随着含水率的上升,面积波及系数增加缓慢。但当含水率高于60％时,随着含水的上升而急剧地增加。文中根据计算结果得出了不同井网条件下,不同注入孔隙体积倍数(或不同含水)时,波及系数与流度比的关系曲线,由这些曲线构成的图版可以用来进行注水井网动态过程的计算和确定油藏采收率。

DETERMINATION OF AREAL SWEEP EFFICIENCY OF PATTERN FLOODING BY USE OF SIMULATOR

In this paper, the result of reservoir simulation in calculating the areal sweep efficiency is given for some well patterns, such as five-spot, seven-spot, direct line drive and staggered line drive. A full picture of water displacement is systematically evaluated and demonstrated in a series of figures that give the areal sweep efficiency for each well pattern in relation to mobility ratio, dimensionless water injection volume or water fraction of proportion. It has been proved that the value of Ea determined by simulator is more close to the real value in reservoir than thatdetermined by other methods. The result can be used to determine the production performance of oil reservoir with corresponding flooding pattern.