摘要
地下多孔介质因具有较大的比面积而对凝析油气流体具有较强的吸附能力 ,多孔介质吸附对凝析油气渗流过程的影响是国内外较为关注的问题。文章根据物质平衡原理 ,利用微元体法重新推导和建立了新的凝析油气渗流微分方程 ,首次将多孔介质吸附影响直接纳入渗流微分方程之中 ,并定义了相应的两相拟压力函数 ,得出了与单相液体渗流微分方程形式上相似的渗流方程 ,然后推导出了渗流过程中地层反凝析油饱和度与压力的关系 ,最后对地层中反凝析油饱和度、吸附相流体饱和度以及两相拟压力与压力的关系和生产过程中地层反凝析油饱和度的动态分布进行了实例计算和分析 ,结果表明 :考虑多孔介质吸附影响与不考虑其影响的凝析油气体系渗流规律差异明显 ,多孔介质对凝析油气渗流的影响较大 ,在工程实际应用中不容忽视。
The porous media underground have a stronger adsorption capacity for condensate gas fluid because of their larger specific surface and the effect of the porous media adsorption on condensate gas flow is a problem which has been followed with interest at home and abroad. In the paper, according to material balance principle, a new condensate gas flow differential equation is rederived and set up by use of the infinitesimal volumn method; the influence of the porous media adsorption is directly introduced into the flow differential equation firefly and relevant two-phase pseudopressure function is defined; a flow equation similar to single-phase liquid flow differential equation in form is obtained; then the relation between formation retrograde condensate saturation and formation pressure in flow process is derived; and then the relation between pressure and retrograde condensate saturation, adsorption fluid saturation and two-phase pseudopressure in formation as well as the dynamic distribution of the formation retrograde condensate saturation are calculated and analyzed by example. The results show that the condensate gas flow law considering the influence of the porous media adsorption is obviously different from the one unconsidering its influence; and the effect of the porous media on the condensate gas flow is greater, which can't be neglected in application to engineering.
出处
《天然气工业》
EI
CAS
CSCD
北大核心
2001年第2期75-78,共4页
Natural Gas Industry
基金
中国石油天然气集团公司"九五"重点科技攻关项目 !(970 5 0 6 - 0 3)
"西南石油学院科技攻关"项目! (Y99- 16 0 )
关键词
凝析气藏
多孔介质
吸附
渗流
反凝析
微分方程
多孔介质
Condensate field,Porous media,Adsorption,Percolation,Retrograde condensation, Differential equation
