摘要
通过定义压敏油藏的无量纲变异系数,得到油藏渗透率变化的控制方程。在采用零维近似解的基础上,结合Laplace变换和Stehfest数值反演求解了无限大边界、定压边界和封闭边界3种外边界油藏单井生产的渗透率变化模型,并预测了这3种模型的渗透率变化趋势。结果表明,在油藏压力下降的同时渗透率会明显下降;随着压力不断减小,压力下降对渗透率变化的影响也逐渐减弱。而不同的油藏外边界会使渗透率呈现出不同的变化规律。
A governing equation of permeability variation is established by defining dimensionless variation coefficient for pressure-sensitive reservoirs.A permeability variation model of single well production with infinite boundary,constant pressure boundary and sealed boundary is solved on the basis of zero-dimensional approximate solution combining with Laplace transformation and Stehfest numerical inversion,and the trends of permeability variation of the 3 boundaries are predicted.The results indicate that reservoir permeability decreases along with the decline of reservoir pressure;as the continuous decline of reservoir pressure,the impact of pressure drop on permeability becomes less prominent;and different reservoir boundaries may lead to different permeability variation.
出处
《特种油气藏》
CAS
CSCD
北大核心
2012年第1期88-91,139-140,共4页
Special Oil & Gas Reservoirs
基金
国家科技重大专项"致密砂岩气有效开发评价技术"(2011ZX05013-022)
关键词
压敏储层
非稳态渗流
渗透率变化
无限大边界
定压边界
封闭边界
pressure-sensitive reservoir
unstable state flow
permeability variation
infinite boundary
constant pressure boundary
sealed boundary
