水平井泡沫酸化分流数值模拟

Numerical simulation on the foam acidizing diversion in horizontal wells

泡沫分流可以有效地解决不同渗透率储层的酸液分布问题。由于水平井具有较长的水平段长度,它可以钻遇储层性质不同的层段。根据泡沫具有的暂堵分流特性,利用泡沫进行酸化可以使得井筒周围得到均匀的酸化解堵。根据施工过程中酸液在水平井筒中的变质量流动,以及酸液自水平井筒流出后进入井筒周围储层,建立了水平井泡沫酸化分流数学模型,研究了沿井筒不同渗透率情况下泡沫酸流动渗流特征。结合井筒流动和井筒往周围地层的渗流,建立两种流动系统的耦合模型并进行求解,对水平井泡沫酸化分流进行了数值模拟,研究成果可为水平井泡沫酸化分流提供理论指导。

Foam diversion can effectively solve the problem of the acidizing fluid distribution in layers with different permeability.A horizontal well may encounter sections with different reservoir properties in drilling because of a longer horizontal-section length.In view of temporary block and diversion characters of foam,the vicinity of a wellbore can be evenly unblocked by foam acidizing.We established a mathematic model for the foam acidizing diversion according to the variable-quality flow of acidizing fluids along a horizontal wellbore as well as acidizing fluid behaviors in reservoir intervals adjacent to horizontal wellbores.Seepage characters of acidizing foam fluids along wellbores under different permeability conditions were also studied.A coupling model for two flow systems was established and solved by means of numerical simulation on the foam acidizing diversion in horizontal wells.These results can give theoretic guidance on the foam acidizing diversion in horizontal wells.