排状交错水平井井网面积波及效率研究

根据低渗透油藏排状交错水平井井网注水开发特点，在流管模型和Beckley-Leverett 方程的基础上， 从理论上推导了考虑启动压力梯度的排状交错水平井井网面积波及效率和油井见水时间的计算公式，解 决了低速非达西渗流的面积及效率理论计算问题和生产井见水时间的确定问题。理论推导计算结果与油 田现场实际情况基本一致，表明该方法科学、合理，可用于定量表征排状交替水平井井网条件下储层的动 用程度，为低渗透油藏开发设计和评价提供理论依据。

Areal sweep efficiency of staggered well pattern of horizontal wells in low permeability reservoirs

By means of characteristics of the staggered well water flooding exploitation in low permeability reservoirs,and on the basis of stream tube model and the Beckley-Leverett equation,the areal sweep efficiency formula and water breakthrough time formula considering start-up pressure gradient were derived for the staggered well pattern of horizontal wells.This theory solved the problems of theoretical calculation of areal sweep efficiency and water breakthrough time on the state of non-Darcy flow.The case study shows that the theoretically calculated results are very close to the reservoir.So this method is scientific and reasonable,and it can be used to quantitatively characterize the reservoir produced degree in staggered well pattern and provide theory basis for development and evaluation of low permeability reservoirs.