摘要
在对油气井进行水力压裂后产生的有限导流垂直裂缝进行研究时,特别是对于泄流面积比较狭长的储层,可采用复合流动模型求解得到接近于实际的近似结果.利用演绎一维流动数学模型,考察天然气渗流的非线性影响,并定义拟时间因子化简控制方程,利用Laplace变换求得无量纲解析解式,联立物质平衡方程后分析拟时间因子的变化规律及其对生产动态的影响.进而利用复合渗流模型分析垂直裂缝气井在定流量和定流压生产的2种典型制度下的动态表现特征,绘制相应的不稳态压力及产量曲线,并采用商业模拟器(Eclipse)对该解析解进行模型的对比验证.结果表明:天然气非线性渗流特点对拟稳态时期的产量及压力特征有较大影响.该研究结果有利于提高对天然气渗流规律的认识,为压裂气井的生产动态分析提供一定的理论参考.
In order to conduct research on finite conductivity vertical fracture of oil and gas wells formed by hydraulic fracturing,especially for the reservoir with relatively narrow drainage area,compound flow model could be used to get approximate results close to actual situation.Consequently,this paper interpreted the one-dimensional flow mathematical model by simplifying the governing equation of natural gas and investigating the non-linear impact of natural gas seepage.Meanwhile,the dimensionless analytical solutions were obtained by using the Laplace transform,then the variation of the pseudo-time factor and its impact on production could be calculated and analyzed according to material balance equation.Furthermore,compound flow model was used to analyze the dynamic characteristics of vertical fractures under constant flow rate or constant pressure conditions,and the Eclipse was applied to verify this model in this paper.The results showed that natural gas nonlinear seepage had a significant influence on the characteristics of pressure and production during the pseudo-steady state period.Also,the results could improve our understanding of seepage flow law of natural gas and provide theoretical foundation for the production performance analysis of fractured gas wells.
出处
《东北石油大学学报》
CAS
北大核心
2015年第4期79-87,10-11,共9页
Journal of Northeast Petroleum University
基金
国家科技重大专项(2011ZX05009-004)
