单砂体内只注不采型注水井供液半径理论模型及应用

随着井网密度逐年加大,待钻井周围钻关注水井数量也相应增加。为了避免在钻井过程中发生事故,必然要对注水过程中不同井距、不同渗透率及不同注入时间等因素下单砂体内压力的分布规律进行研究,进而对钻关距离和钻关时间等方面进行调整。根据渗流力学理论,建立了常见的单砂体内只注不采情况下的注水井供液半径和地层压力预测数学模型,绘制了供液半径和泄压半径理论图版。对单砂体内压力分布影响因素进行了详细分析,单砂体的渗透率对地层压力系数的影响较小;不同注水时间单砂体内地层压力系数差值较大,尤其是单砂体的半径较小时差值更大;单砂体的半径对地层压力系数的影响较大,尤其是单砂体的半径较小时影响更大。

The establishment and application of the feed liquid radius model about the injection well for injection and no production type in single sand

With the well spacing density increasing year by year,the amount of drilling and shut-in wells around the impending drilling wells increase accordingly.In order to avoid the accident in the process of drilling well,we should study the pressure distribution law under the different well spacing,different permeability and different injection time and other factors in single sand.And then we can adjust the distance of drilled-shut well,the time of drilled-shut well and other aspects.According to the theory of the fluid mechanics,we establish the common mathematical model of the feed liquid radius and formation pressure prediction about the injection well under the condition of injection and no production in singe sand.And then we draw the chart of the feed liquid radius and pressure release radius.At last,the pressure distribution factors are analyzed in detail.We conclude: the permeability of the single sand body affects the formation pressure coefficient less;the difference of the formation pressure coefficient is bigger under the condition of different water injection time,especially the radius is smaller,the influence is bigger in singe sand;the radius of the single affects the formation pressure coefficient bigger,especially the radius is smaller,the influence is bigger.