摘要
为揭示天然气水合物试采工程中储层物理参数演化规律,建立了耦合化学分解和气、水两相渗流物理场的数学模型,并采用有限单元法进行求解,对不同降压幅度、初始绝对渗透率和含水饱和度等影响下的储层物理参数的时空演化规律进行研究。结果表明:井筒开始降压后,井周迅速形成压降漏斗,压降辐射范围随时间逐渐增大,且水合物分解范围和压降范围呈现明显的一致性;井筒降压后短时间内产气速率达到峰值,该峰值随降压幅度和初始绝对渗透率的增大而增大,随初始含水饱和度的增大而减小;水合物分解速率和渗透率增大速率与降压幅度和初始绝对渗透率成正相关,与初始含水饱和度成负相关。
In order to reveal the evolution principle of reservoir physical parameters in natural gas hydrate test mining engineering,in this paper the effect of different depressurization gradients,initial absolute infiltration,and water saturation on the temporal and spatial evolution of reservoir physical parameters is studied.This is accomplished by establishing a mathematical model of coupled chemical decomposition and gas-water two-phase seepage physical field with adoption of finite element method.The results show that a pressure drop funnel is rapidly formed around the wellbore after its pressure begins to decrease.The pressure drop radiation range increases with time,and the hydrate decomposition range and pressure drop range show obvious consistency.Within a short time after the pressure drop,the gas production velocity reaches its peak,which increases with the increase of depressurization gradient and the initial absolute permeability,and decreases with the increase of the initial water saturation.The hydrate decomposition rate and the permeability increase rate are positively correlated with the depressurization gradient and the initial absolute permeability but are negatively correlated with the initial water saturation.
作者
梁伟
赵同彬
陈中伟
栾恒杰
程先振
张继成
LIANG Wei;ZHAO Tongbin;CHEN Zhongwei;LUAN Hengjie;CHENG Xianzhen;ZHANG Jicheng(State Key Laboratory of Mining Disaster Prevention and Control,Co-founded by Shandong Province and the Ministry of Science and Technology,Shandong University of Science and Technology,Qingdao,Shandong 266590,China;College of Mining and Safety Engineering,Shandong University of Science and Technology,Qingdao,Shandong 266590,China;School of Mechanical and Mining Engineering,University of Queensland,Brisbane,Queensland 4072,Australia)
出处
《山东科技大学学报（自然科学版）》
CAS
北大核心
2020年第2期53-60,68,共9页
Journal of Shandong University of Science and Technology(Natural Science)
基金
山东科技大学研究生创新基金项目(SDKDYC190235)
关键词
天然气水合物
分解
渗流
耦合
有限单元法
natural gas hydrate
decomposition
seepage
coupling
finite element method
