摘要
采用球-棍标准孔道和孔隙结构两种刻蚀模型开展水气分散体系驱替实验,观察微气泡形态变化和运动特点,并结合数值模拟方法对实验现象及驱油机理进行定量分析。实验中观察发现:微气泡群可以打破横向孔隙内流体的压力平衡状态,增强流体整体的流动性;气泡在渗流过程中呈现特有的膨胀-收缩的振动现象,该现象在水驱和气驱过程中几乎观察不到,气泡振动可加速油滴吸附、加快油滴膨胀和促进原油乳化,进而提高微观驱油效率。结合实验数据进行气泡振动作用的数值模拟分析发现:微气泡振动具有正弦函数特点,能量释放过程满足指数衰减规律;与气驱前缘界面相比较,微气泡表现出明显的“刚性”特点;微气泡振动所释放的能量改变渗流流场的稳定性,使流线显著变化;在驱油过程中,数量巨大的微气泡能充分发挥振动作用,促使剩余油运移,验证了水气分散体系提高微观驱油效率的机理。
Two etching models,the spherical-rod standard pore channel and the pore structure,were used to conduct displacement experiments in the water-gas dispersion system to observe the morphological changes and movement characteristics of microbubbles.Additionally,numerical simulation methods were employed for quantitative analysis of experimental phenomena and oil displacement mechanisms.In the experiment,it was observed that microbubble clusters can disrupt the pressure equilibrium state of fluids within the transverse pores,and enhancing the overall fluid flow;bubbles exhibit a unique expansion-contraction vibration phenomenon during the flow process,which is nearly unobservable in water flooding and gas flooding processes.Bubble vibration can accelerate the adsorption and expansion of oil droplets,and promote the emulsification of crude oil,thereby improving microscopic oil displacement efficiency.Combining experimental data with numerical simulation analysis of bubble vibration effects,it was found that microbubble vibrations exhibit characteristics of a sine function,and the energy release process follows an exponential decay pattern;compared to the gas drive front interface,microbubbles exhibit a significant“rigidity”characteristic;the energy released by microbubble vibrations alters the stability of the seepage flow field,resulting in significant changes to the flow lines;during the oil displacement process,the vast number of microbubbles can fully exert their vibrational effects,facilitating the migration of residual oil and validating the mechanism of the water-gas dispersion system enhancing microscopic oil displacement efficiency.
作者
张墨习
陈兴隆
吕伟峰
韩海水
ZHANG Moxi;CHEN Xinglong;LYU Weifeng;HAN Haishui(University of Chinese Academy of Sciences,Beijing 100190,China;Institute of Porous Flow and Fluid Mechanics,Chinese Academy of Sciences,Langfang 065007,China;CNPC Science and Technology Research Institute Co.,Ltd.,Beijing 100083,China)
出处
《石油勘探与开发》
EI
CAS
CSCD
北大核心
2024年第6期1363-1373,共11页
Petroleum Exploration and Development
基金
国家重点研发计划“利用大型油气藏埋存二氧化碳关键技术标准研究与应用”(2023YFF0614100)
中国石油天然气股份有限公司重大科研项目“多元气驱提高采收率技术研究”(2023ZZ0410)。
关键词
水气分散体系
微观刻蚀模型
微气泡振动
弹性能量
驱油机理
water-gas dispersion system
micro-etching model
microbubble vibration
elastic energy
oil displacement mechanism
