当油田开采进入特高含水后期,分层注水已经不能有效提高采收率,聚合物驱成为提高油田采收率最有效的方式之一,而油田分层注入聚合物驱精准调控成为了一个重要问题.为满足现场分层注入聚合物驱节流压降需要,利用仿真软件对 3 种结构的井下分层节流装置进行了数值模拟,得到流体的压力云图,分析了压力损失机理和规律,确定了节流压降规律与节流装置的管芯环数、环空距离的关系.分析结果表明:在相同的管芯环数和环空距离条件下,流线型节流装置的压降最大,压降调节能力最强,通过建立合适的管芯环数和环空距离可满足油田分层注入流量调节的需要;根据得到的节流压降规律,通过改变管芯伸入环数可实现现场分层注入聚合物驱实时精准调控目的.所得结论对现场分层注入聚合物驱流量精准调控具有指导意义.
As oilfield development progresses into the late stages with high water content,layered water injec-tion is no longer an effective method for increasing oil recovery.Polymer flooding has become one of the most effi-cient techniques for enhancing oil recovery,and precise control of layered polymer flooding is becoming a signifi-cant concern.To meet the requirements for throttling pressure drop during on-site layered polymer flooding,numer-ical simulations were conducted on three different types of downhole layered throttling devices using simulation soft-ware.In addition,the pressure cloud diagram of the fluid was obtained,the mechanisms and rules of pressure loss were analyzed,and the relationships between the pressure drop and the number of core rings and annular spacing of the throttling device were determined.The results show that,given the same number of core rings and annular spacing,the streamline throttling device exhibits the highest pressure drop and the most robust pressure regulation capability.By establishing an appropriate number of core rings and annular spacing,it is possible to meet the needs of adjusting the flow rate for layered polymer flooding in oilfield.Based on the pressure drop rules obtained,real-time and precise control of layered polymer flooding on site can be achieved by altering the number of core rings inserted.The conclusions obtained are of guiding significance for precisely controlling flow rate during layered polymer flooding.