摘要
以低渗透油藏中可能存在的裂缝网络为研究背景,基于广义达西定理和分形理论研究了Bingham流体在"点到圆"形树状分叉网络的启动压力梯度.研究得到不包含任何经验常数的启动压力梯度表达式,该表达式显示启动压力梯度不仅与屈服应力有关,而且还与分叉比、分叉角度、母管直径和总级数等分叉网络的微结构参数有关;渗透率只与网络微结构参数有关,与屈服应力无关.研究结果还表明启动压力梯度随着直径比和渗透率的增大而减小,随着长度比的增加而增加.研究结果将会为石油开采等实际应用提供一定的理论指导.
In this paper, based on the generalized Darcy law and fractal theory and the fact that the fractured network may exist in the oil deposit, the starting pressure gradient for Bingham fluids in the fractal disk-shaped branched networks is investigated. The results show that the starting pressure gradient for Bingham fluids is a function of the yield stress and network microstructural parameters such as the branching ratio, the branching angle and the branching number. The function is an analytical formula, which contains no empirical constant. The permeability for Bingham fluids is only dependent on network microstructural parameters and independent of the yield stress. The results also show that the starting pressure gradient decreases with the increase of the diameter ratio and the permeability and increases with the increase of the length ratio. The results have potential applications in petroleum recovering.
出处
《华中师范大学学报(自然科学版)》
CAS
北大核心
2013年第2期195-199,共5页
Journal of Central China Normal University:Natural Sciences
基金
油气藏地质及开发工程国家重点实验室(西南石油大学)资助项目(PLN1205)
关键词
裂缝网络
分形理论
渗透率
启动压力梯度
the fractured network
fractal theory
permeability
the starting pressure gradient