基于流管法的普通稠油水驱波及系数计算方法

根据普通稠油油田面积注水开发的特点，为了解决注水平面矛盾的问题，基于流管法得到了注采单元面积波及系数、时间和含水率的计算公式，并成功运用到反九点井网，从数学理论上初步解决了两相驱替条件下面积波及系数的计算问题。研究结果表明，稠油油藏油井见水后，含水率迅速升高，面积波及系数增速减小；反九点井网边井和角井的见水时间和面积波及系数不同，需要采用不同的工作制度使水驱更加均匀；理论计算结果与数值模型计算结果一致。该方法为后续面积波及系数理论研究的开展提供理论基础。

Calculation of sweep efficiency for water flooding development of conventional heavy oil using the stream-tube method

In terms of the characteristics of pattern flooding of conventional heavy oil reservoirs, to eliminate the problems related to water-flooding plane, stream-tube method has been used to develop equations for calculation of sweep efficiency, timing and watercut on unit area of flooding operations. These newly developed equations have been applied successfully in inverse 9-point pattern successfully for the first time to calculate areal sweep efficiency under two-phase flooding theoretically. Research results show producers for heavy oil development may have quickly increasing watercut and rapidly decreasing areal sweep efficiency after water breakthrough. Since wells on the boundary or corners of the inverse 9-point pattern may have different water breakthrough time and areal sweep efficiencies, different flooding systems shall be deployed to achieve more evenly distributed water-flooding performances. Theoretical calculation results are consistent with numerical simulation conclusions. The innovative calculation methods may provide reliable theoretical foundation for future studies for areal sweep efficiency.