摘要
异常高压气藏具有介质变形的性质,介质变形后的渗透率一般随压力变化呈指数关系。考虑渗透率变化对气井产能的影响,推导出了新的异常高压气井产能方程。基于新的气井产能方程,计算并分析了渗透率应力敏感参数对气井产能的影响。介质的应力敏感效应使气井产能降低,应力敏感效应越强,气井产能降低幅度越大。尽管存在应力敏感效应,但在无阻流量50%以内,气井产量与井底压力仍呈很好的二项式直线关系。应力敏感效应越弱,直线关系越好,但据此预测的气井无阻流量差异则随应力敏感效应的增强而迅速增大。该研究对深入了解异常高压气井的产能变化特征及试井分析方法具有重要的指导意义。
Abnormal high pressured gas reservoirs has feature of media deformation, whose post-deformed permeability is always exponentially related to pressure. Taking into account of impact of permeability variation on productivity of gas well, a new productivity equation for gas well with abnormal high pressure is developed. Based on the new productivity equation, influence of stress sensitivity parameter of permeability on productivity at gas well is calculated and analyzed. Productivity of gas well decreases due to stress sensitivity effect of media, the stronger the stress sensitivity effect, the wider range of productivity of gas well declines. Even with stress sensitivity effect, within 50 percent of AOF, binomial relationship is still well fit for rate of gas well and flowing pressure at bottom hole. The calculation shows that the weaker the stress sensitivity effect, the better the linear relationship is, however, the difference of predicted AOF of gas well rapidly becomes larger as increasing stress sensitivity effect. This study has important guiding meaning for thoroughly understanding productivity behavior and well test technique in gas reservoirs with abnormal high pressured.
出处
《油气井测试》
2008年第4期5-7,共3页
Well Testing
关键词
异常高压气藏
应力敏感
产能方程
流入动态曲线
产能试井分析
gas reservoir with abnormal high pressured, stress sensitivity, productivity equation, inflow performance relationship curve, productivity test analysis
