提高油藏数值模拟历史拟合精度的方法

油藏数值模拟中,通常应用达西定律根据地层系数对流量进行劈分,未考虑低渗透层启动压力梯度的影响,因而其劈分的小层流量与实际生产情况不符,导致历史拟合精度较低.注入、产出剖面是确定小层流量的最佳资料,利用注入、产出剖面测井资料进行小层硫量劈分,拟合效果理应有所改善.给出了利用注入、产出剖面进行流量劈分的方法,对于没有生产测井资料的井,可根据启动压力梯度与渗透率的相关关系采用考虑启动压力的流量劈分模型.以大庆油田杏十～十一区试验区块为例,将注入、产出剖面测井资料及考虑启动压力的流量劈分模型用于油藏数值模拟,历史拟合精度明显提高,区块综合含水符合率提高约7%,单井含水符合率提高约10%.图5表2参15

Method for improving history matching precision of reservoir numerical simulation

During reservoir numerical simulation, Darcy's law is usually used for splitting the flow based on formation capacity, without considering the effects of threshold pressure gradient of low-permeability. So the flow rate of the split layer is not consistent with the actual production, which results in poor history matching precision. Injection and production profiles are best information for determining the flow rate of individual layers. The matching is improved by flow split utilizing injection and production logs. To those wells without production logging, the flow split model is to be adopted according to the relationship of start pressure gradient and permeability. The application in the Unit 10-11 of Daqing Oilfield indicates that the history matching precision of reservoir numerical simulation was obviously improved, the coincidence rate of composite water cut of the whole area and that of single wells were increased by about 7% and 10% respectively.