低渗透油藏非达西渗流面积井网产油量计算方法

根据低渗透油藏注水开发的特点,应用室内实验得到的低速非达西渗流基本公式以及流线积分方法和单元分析方法,推导出了四点法、五点法和反九点法面积井网的产量计算公式,称为ND-Ⅰ法。利用大庆低渗透油田生产数据,建立了启动压力梯度和渗透率的关系式,证实了非达西渗流存在的普遍性。提出了启动角和启动系数的概念,用于定量表征不同井网条件下储层的动用程度,为低渗透储层的油藏评价和开发设计提供了理论依据。

Oil production calculation for areal well pattern of low-permeability reservoir with non-Darcy seepage flow

Based on the exploitation characteristics of low-permeability reservoirs and the basic formula of non-Darcy flow with low velocity obtained from laboratory experiment, the yield formula for calculating the 4-spot, 5-spot and invert 9-spot areal well patterns were deduced by using the flow line integral method and element analysis method named as ND-1 method. Based on the production data of low-permeability reservoirs in Daqing Oilfield, the relationship between startup pressure gradient and permeability was established. The existence universality of the non-Darcy seepage flow was verified. The concept of startup coefficient was put forward to characterize the employing degree of reserve in different well pattern and to provide theoretical foundation for reservoir evaluation and development design of low-permeability reservoirs.