摘要
针对天然裂缝性致密砂岩油藏,研究了3种外边界条件(无穷大、定压、封闭)及内边界定产量生产问题,并建立了考虑应力敏感性和交界面阻力的不稳定渗流试井分析模型。先对此模型作参数无量纲化处理;然后通过零阶摄动法以及利用Laplace变换,求得线性化后的无因次储层压力的Laplace空间精确解;最后采用Stehfest数值反演方法,绘制了3种不同边界致密砂岩双重介质复合油藏偏心井压力和压力导数的典型图版。通过图版分析可知:渗流过程划分为9个阶段;随着偏心距不断增大,径向流阶段持续的时间越长;一区和二区的交界面阻力越大,"驼峰"越高;应力敏感系数越大,相对于一区来说二区压力和压力导数曲线上翘更明显。
For natural fractured tight sandstone oil reservoirs,the problem about fixed output was addressed in 3 outer boundary conditions（infinite boundary, constant pressure and closed boundary）and inner boundary conditions,to build a well test analysis model for unsteady seepage flow in view of stress sensitivity and interface resistance.Firstly,the model of dimensionless parameter was processed,the zero-order perturbation method and the Laplace transform were used to get the exact solution of dimensionless reservoir pressure in the Laplace space with the linearized model.Finally,the method of Stehfest numerical inversion was used, and a typical chart of pressure and pressure derivatives under three different boundary conditions were drawn off-center well of composite dual-porosity tight sandstone oil reservoirs.From the analysis of the plate,it was concluded that,the seepage process was divided into nine stages.With the increase of the eccentricity,the longer that the radial flow continues.The bigger the interface resistance between NO.1 and NO.2 blocks,the bigger the stress sensitive coefficients are.Compared to the NO.1 block, NO.2 block＇s pressure curve and pressure derivative curve upturned more obvious.
出处
《石油化工应用》
CAS
2017年第7期19-25,共7页
Petrochemical Industry Application
基金
甘肃省自然科学基金
项目编号:1606RJZM092
甘肃省青年科技基金
项目编号:1606RJYM259
1506RJYM324
关键词
偏心井
复合油藏
应力敏感
交界面阻力
零阶摄动
off-center well
composite oil reservoirs
stress sensitive
interface resistance
zero-order perturbation
